Model Engine Maker
Engines => From Plans => Topic started by: sshire on September 02, 2015, 02:09:53 AM
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Lady Godiva Rides Again - Episode 1
Roy Ozouf’s Coventry Engine
“Lady Godiva, was an 11th-century Anglo-Saxon noblewoman who, according to a legend dating back at least to the 13th century, rode naked – only covered in her long hair – through the streets of Coventry in order to gain a remission of the oppressive taxation imposed by her husband on his tenants.”
At NAMES, Kvom and I were looking at a Roy Ozouf designed oscillating engine, the Coventry. I apologize for not knowing who built this excellent example.
(http://i1126.photobucket.com/albums/l604/sshire/NAMES%20-%202015/Names%20-%20Final%20group/NAMES%202015-96.jpg) (http://s1126.photobucket.com/user/sshire/media/NAMES%20-%202015/Names%20-%20Final%20group/NAMES%202015-96.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/NAMES%20-%202015/Names%20-%20Final%20group/NAMES%202015-97.jpg) (http://s1126.photobucket.com/user/sshire/media/NAMES%20-%202015/Names%20-%20Final%20group/NAMES%202015-97.jpg.html)
While building the 1/4 horse, I had been studying the plans in Roy's book and devising some sort of machining plan for the side frames.
The drawings in the book are very well done, as is the text.
The Side Plates
Starting with the side plates, two pieces of .5" aluminum plate were sized to 6”x8” and squared up. This absolutely looks like a job for CNC. Since the Bridgeport can't even spell "CNC", the rotary table and DRO will suffice.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-1.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-1.jpg.html)
The first operation was to spot drill all 16 pivot holes and put each into the DRO memory. Since both sides of both plates will need to be laid out, this will save a bit if time.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-2.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-2.jpg.html)
Next, a Dykem bath, scribes, odd leg calipers and dividers to do the layout on both sides.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-3.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-3.jpg.html)
All 16 holes were drilled and reamed 3/16"
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-4.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-4.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-5.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-5.jpg.html)
The horizontal and vertical cuts were done in the vise. The part then moves to the rotary table.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-7.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-7.jpg.html)
I wanted radiused corners on the inside recess as Roy suggests. ¼" corner radius carbide end mill (.0625 radius)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-6.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-6.jpg.html)
With the rotary table centered under the spindle and a 3/16" locating pin, the part was milled to .125 depth. Each set of holes has a turning radius.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-8.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-8.jpg.html)
The center completed on both sides.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-9.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-9.jpg.html)
Back in the vise, decorative elements were milled.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-13.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-13.jpg.html)
Next the outside was milled with a .25” carbide center cutting end mill.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-10.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-10.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-11.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-11.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-12.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-12.jpg.html)
I was concerned about the cutoff jamming while clamped in the vise.
After indicating the part, the final cut, which broke the part free, was done clamped to the mill table.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-14.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-14.jpg.html)
Cutoffs
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-15.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-15.jpg.html)
Some initial cleanup with Oliver. I’m waiting for some small Cratex wheels and points for the Foredom handpiece for final cleanup and polishing of the recess.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-16.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-16.jpg.html)
Including layout, each side took about 7 hours. If this was a profit-making venture, I could think about CNC. Since it's definitely not, I'm only spending my time. And, George Britnell has gained even more respect ( if that's possible ) after doing this plate.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-17.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-17.jpg.html)
Now, the whole process gets repeated for the other plate.
Then, the plates will be aligned with dowel pins to through bore the 7/8" hole for the cylinder pivot.
Both frames will be sent to Cletus at the Close Enuf Machine Shop's Metrology Division in beeeeutiful Springbucket, TN for a QC check.
Stay tuned for the next thrilling episode.
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Stan that's some amazing work your turning out. I am glad to see you pushing your limits because we never know them till we try just what we can and cannot do. Excellent work buddy and I'm sure Cletus will agree with his QC Deptartment.
Don
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Very impressive start Stan. Can't wait for the next installment!!
Bill
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Thanks. That was proof of concept to see if I could do it in metal. Plan B was to do the CAD drawing and 3D print. Then, send that to Cattail Foundry as a pattern to be cast in aluminum. No need as I'm happy with the part I made.
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Very nice work Stan!
Don't you just love those 3 flute carbide end mills?
Fun to see you on to a new venture.
Best regards,
Dave
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Dave
I'd never used them before. I'm very happy with the finish and they go through the 6061 like butter. After doing a speed calculation for the ¼" ones and cranking the Bridgeport to its max speed...wow. I kept them pretty wet with coolant and had the air nozzle getting chips out of the path. I'm sold.
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Looking good Stan, I'll be following along.
J
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Stan to complete the legend: Godiva required the townsmen to remain indoors at the time of her ride but one man looked at her out of his window and was struck blind...from that point on we find the English were using the term "Peeping Tom".
Its a pretty little thing but is based on a real engine? or one of those Victorian toys? (Like my :old: AGE)
Jo
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Stan,
Looking good.......giving Jason a run on the fabrication front!
:popcorn: :DrinkPint: on standby!
Cheers Kerrin
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That's a good looking engine and a good start on your version :praise2: I will be following along :ThumbsUp: :ThumbsUp: :wine1:
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Thanks for the interest in this build.
Jo
As KVOM posted earlier, the name of the engine is from Don Coventry, an Englishman, who found a similar engine in a surplus store and published a picture in Model Engineer. It's unusual for having the pivot at the bottom of the cylinder rather the at the center, as is the case with the McOnie.
There is no mention of whether the engine that was found was a model or a full-size engine. If anyone knows, I'd love to find out.
There is also some confusion as to whether Peeping Tom was struck blind or dropped dead. The legend continues.
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There is also some confusion as to whether Peeping Tom was struck blind or dropped dead. The legend continues.
If he was caught looking at my casting sets I know what would have happened to him ;)
Jo
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After NAMES I was surprised you did the quarter horse before this one, but now it's well under way. Other than making the SW model I've done nothing as I pledged myself to finish the paddle engine before starting anything else.
I did investigate using Shapeways to make the 4 frame separators, and ordered an example in "metallic plastic". Probably won't go that way, and the same parts in metal are two expensive. For me those parts appear difficult to make as drawn; I have no CNC lathe and the shapes look hard to duplicate exactly.
I plan to make the side frames from steel, as I have a quantity of 1/2" plate lying about, and no aluminum. Given the speed with which you work, I'm sure you'll have resolved any problems and be finished before I even start. So I'll be following along.
Here's the video I took at the show:
https://www.youtube.com/watch?v=zHMdw0xglFI
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So as you have a bigger ME archive than me Jo how about looking out the article?
Vol 148, No 3677, pg 370 and Vol 166, No 3849 also page 370 look the most likely.
The spacers should not be too hard to turn, just turn to length, centre drill each end, turn & thread the spigots and the rest is between ctrs work - cut the tapers with a round nose tool to leave the raised middle then use a form tool to round it over.
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As requested.
Jo
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Thanks Jo.
I see the original has separate bearing caps for the crankshaft bearings, this would be a good idea as you could get the crank out without having to pull the whole engine to bits :)
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Thanks so much, Jo. Your library is most impressive.
Jason
The Ozouf drawings do have separate bearing caps. The engine at NAMES has the bearing cap screws recessed. Not to my liking. Studs and Otto nuts for my build.
Philjoe picked up some bronze drops which I got from him at R&T last month. I now have a lifetime supply of bronze round for bearings.
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Beautiful work, Stan. I never cease to be amazed at how quickly your skills have developed.
I'll be astounded if it turns out that this engine is a model of a real engine actually used in a practical application. From an engineering viewpoint, it seems to me that making the cylinder oscillate is simply asking for a legion of mechanical problems. It does, however, make a beautiful and exciting model, full of unusual and complicated motions.
Lady G should have lived in Hollywood. A naked woman riding a horse down the street would hardly be noticed there.
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And no fewer Peeping Toms
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Hollywood? Philadelphia just had the annual Naked Bike Ride. They photobombed a wedding photo shoot.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/36D8FB81-DF5A-4D73-AFF3-71B723216052.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/36D8FB81-DF5A-4D73-AFF3-71B723216052.jpg.html)
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Ah, yes, the naked bike ride.
I've always thought that it would be far more entertaining if held in January.
Tell me, do they wear helmets? If so, why?
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It's the smart think to do. Protection for one vital part
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Stan buddy, with the RE, the Quarter Horse and now this sizeable new engine, and all the shows you have been attending, you may be needing a bigger means of transporting your "iron" from place to place. :ROFL:
Bill
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Bill is this the sort of transport you are suggesting? ;)
(http://thumb9.shutterstock.com/display_pic_with_logo/462787/462787,1311791206,2/stock-photo-truck-with-metal-scrap-in-the-industrial-area-81760033.jpg)
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http://www.prevostcar.com
Cletus
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I can think of a fair few types of steam ship engine that had oscillating cylinders. I have a book at home called 'steam at sea' which has some nice pictures. IIRC they were popular for paddle steamers as they were low height. https://en.wikipedia.org/wiki/Marine_steam_engine#Oscillating
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It's the smart think to do. Protection for one vital part
I doubt that people who ride naked through the streets have anything in their heads worth protecting.
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Stan, what a start. Looking forward to more. Cheers, Hugh.
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Lady Godiva Rides Again - Episode 2
Roy Ozouf’s Coventry Engine
Both side plates have been milled. Between working on other parts, I'll attack removal of the milling marks from the recesses. As careful and precise as I've tried to be on the D.O.C. of .125", there are still minor variations that must go.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-18.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-18.jpg.html)
With a combination of various grades and shapes of Cratex on the Foredom hand piece, die polishing stones and Scotch-Brite disks, I got to this point in about an hour.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-20.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-20.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-19.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-19.jpg.html)
Frame Spacers
The drawing of the four frame spacers shows a double taper one-piece spacer. I wanted either a painted or powder-coated spacer with a brass center. Nothing for it but to make it in pieces.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/8d427bee-996f-42a1-80c3-ee085a4a4d14.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/8d427bee-996f-42a1-80c3-ee085a4a4d14.jpg.html)
With a long bar of .5” 6061 round in the collet, 10 pieces were parted off. I only need eight, so, two for insurance.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-21.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-21.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-22.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-22.jpg.html)
First, one end was turned to diameter, drilled and tapped. The, an indexible profiling tool. Compound at 5 degrees. Taper cut taken.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-23.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-23.jpg.html)
Family shot
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-24.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-24.jpg.html)
A form tool was made and hardened for the brass centers.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-25.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-25.jpg.html)
The parts for one frame separator.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-26.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-26.jpg.html)
Assembled
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-27.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-27.jpg.html)
All finished
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-28.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-28.jpg.html)
A few possibilities for the aluminum segments of the spacers.
a. Powder coat the aluminum (most likely black to contrast with the brass.
b. Painted and clear coated.
c. Clear powder coat
d. Bead blast and clear coat (either paint or powder.}
I’ll make up some test bits of aluminum and try each finish. Then, we can vote.
BTW, I did use all ten blanks to get the eight parts. One broken tap and a total (not paying attention) muckup on the other.
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Man....those look fantastic Stan! Anxious to see what finishing technique you settle on after the trials. The black and brass sounds very appealing though. Glad to see an update on the Coventry.
Bill
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Bill
Thanks. After using the files and the abrasive sticks (tedious) I ordered the Cratex "Introductory Kit." BTW, best price was Midway (gunsmith supplies.) Various shapes and mandrels in all 4 grits. Those in the Foredom hand piece made pretty quick work of leveling out the surface. I did finish with a 400 grit Borite stick and honing oil then the 60 and smaller micron Scotch-Brite wheels on the Foredom Bench Polisher.
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That is a lot of work Stan and both sides of each side plate right? Even with the Foredom that would be tedious but the results look great.
Bill
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Yes. Four sides. It won't halt progress as the finish doesn't impact anything.
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Good Lord, that thing has more curves than Jennifer Lopez :mischief:. Vern, that's some sweet metal carving :ThumbsUp:. I guess the ProTrac would be a lot faster, but, you can buy a bunch of Craytex for that many duckies. However, a man of your stature and means might should be the first on the forum to break one out :stir: :stir:. I'm liking the sound of black and polished brass. Now, just out of curiosity, what style of milling cutter did you employ ?
Cletus
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Thank you, Cletus
Inside cuts all with 1/4" 3-flute carbide radiused (.0625 radius) center-cutting end mill.
Outside: 3 flute 1/4" straight center cutting end mill.
The BP was cranked up as fast as it would go (3,000+ rpm) which was slower than the RPM calculations.
Plenty of Cool Tool fluid. (My fluid dujour)
Actually, Scott Nelson (Cheepo45) has Protrak Bridgies at the U of Delaware Engineering shop. Along with a cherry HLV-H and a FULL set of 5C collets (fractional, number and letter)
Vern
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Why your welcome Vern. Now, if I may; with what process do you administer Kool Tool to keep your tool cool :shrug:
Cletus
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Lab wash bottle and acid brush
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I sure am enjoying my 1 gallon KoolMist system.
Cletus
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Stan I think we're going to call you " Cool Hand Luke", that is just to cool buddy. You just keep coming up with great results.......... :ThumbsUp: Oh! And did I say I........like.......... :Love:
Don
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Thanks, Don. Only 79 more parts to go.
E
My concern about the Cool Mist was coolant misted all over. How contained is it ?
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Pretty much from a vapor to a flood or just air
E
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If it has 3 flutes and cuts to the center is is still a slot drill?? :lolb: :lolb:
Stan your parts (engine parts that is) are looking great!
Dave
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Parts? Wait until you see my nuts :lolb:
I still am not understanding the "advantage" of a non-center-cutting end mill.
Slotting drill? :thinking:
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I still am not understanding the "advantage" of a non-center-cutting end mill.
Don't worry Stan, I've accepted that it is another lost cause ::)
And best I don't say anything about your nuts :hellno:
Jo
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Lady Godiva Rides Again - Episode 3
Roy Ozouf’s Coventry Engine
Yes! Another episode.
Since the cylinder pivots from the bottom, the next group of parts begins with the pivot shaft and works upward.
I decided to turn the bronze bushings first and then turn the pivot shaft to fit.
Turned to diameter, then drilled and bored.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-29.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-29.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-30.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-30.jpg.html)
Parted off
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-31.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-31.jpg.html)
The pivot shaft was turned to diameter and the ends were turned smaller to fit the bushings.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-51.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-51.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-52.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-52.jpg.html)
First, a ⅛” x 2.065” deep hole.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-53.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-53.jpg.html)
Then larger holes. Finally got to use the small hole gages.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-36.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-36.jpg.html)
Finally, tapped 3/8”-24.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-56.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-56.jpg.html)
The drilling and tapping were repeated on the other end of the pivot shaft
The side plates were indexed together using dowel pins in the ⅛” holes and indicated on an angle plate. The feet were leveled as they will be the reference surface for the next operation.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-39.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-39.jpg.html)
That was in preparation to machining and fitting the bearing caps.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-59.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-59.jpg.html)
Each bearing cap was rounded on the rotary table.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-60.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-60.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-42.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-42.jpg.html)
Since I had left plenty of extra material to clamp the parts on the rotary table, a hogging bit made quick work of removing most of it.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-43.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-43.jpg.html)
Now, with the side plates oriented correctly, a slot was milled with a center-cutting end mill and the bearing caps were fitted.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-44.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-44.jpg.html)
Next, the glands for the pivot shaft. Threads single pointed.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-64.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-64.jpg.html)
Knurling, drilling, reaming and two pieces of Delrin for packing were made.
The family picture of the pivot shaft and associated parts.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-46.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-46.jpg.html)
And, a family picture of everything to this point.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-47.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-47.jpg.html)
Now, the pivot block. The rough piece.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-67.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-67.jpg.html)
The usual operations. Squaring, drilling, reaming, etc.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-68.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-68.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-69.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-69.jpg.html)
A test fit with the pivot shaft. It has had two ports and two mounting holes completed off-camera.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-70.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-70.jpg.html)
Drilling the ports in the pivot block.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-71.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-71.jpg.html)
Almost finished with the machining
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-72.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-72.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-73.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-73.jpg.html)
Bottom cylinder cover
The bottom cover is screwed only the pivot block. It is 2” in diameter. Having no 2” brass round in stock, it will be made from ¼” plate.
First milling to thickness.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-74.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-74.jpg.html)
Then, a ⅛” blind center hole. This will be used after this operation to align the cover with the pivot shaft and block. The holes on either side are to secure it for turning.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-75.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-75.jpg.html)
A 2.25” aluminum round with a matching set of holes.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-76.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-76.jpg.html)
With the brass secured to the aluminum, it was indicated in the 4-jaw.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-77.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-77.jpg.html)
A trepanning bit was used here. Since my brass plate was 2” wide (the diameter of the cover), I began wider and kept moving in until I had a full circle.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-78.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-78.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-79.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-79.jpg.html)
The 1” diameter center boss was turned and then the piece was moved to the mill and indicated.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-80.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-80.jpg.html)
Bolt hole circle, countersunk mounting holes and intake and exhaust holes. The central mounting holes will be plugged.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-81.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-81.jpg.html)
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Loads of nice work in this update Stan. It's really coming along and looking nice too!! Well the mini-mic may be passé but not too passé to use I see :LittleDevil: Works well with those small hole gages doesn't it ??
Bill
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Thanks,Bill.
You are right. It's like the ½" mike was made for those gages.
Just got a very heavy package from Online Metals so progress should ramp up.
Although with two shows in October (Rhode Island and American Precision Museum in Vt) there will be some breaks.
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Vern, by God, that's some mighty fine metal whittling you've done, those frame segments are simply stunning, looking "as cast". I'll admit though, I'm quite surprised to see you still using that far eastern POS drill and three jaw chuck on the lathe ( knew there was a reason for that wide angle center punch.) Would have thought a chap of your stature would have Albreich, Bison, and or, Buck. I'm thinking of a self centering 6 jaw Bison for Mr. Rawhide as his next toy. Just curious, but, have you ever looked into the proper diameters of piece of stock to be knurled, lot more to it than one would think :noidea:. Time to run the traps and feed the milk cow, gotta go boys.
Cletus
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Stan your work is just outstanding buddy and I am digging this engine built and did I say ......I like........... :ThumbsUp:
:popcorn:
Don
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When I was modeling the engine in SW, I had the idea of not using bearing caps, but rather making the frames to include the cap profile and boring holes for the bushings, which would be loctited to the frames. The crankshaft would then be inserted before the sides were fastened together with the tie rods. I'm wondering how often the crankshaft would need to be removed when assembling the other pieces.
Any thoughts?
And nice work there btw. :cheers:
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Kirk
Since the con rod is split, it would seems that your idea would work. Since I've got many more parts to make before final assembly, this is only a guess.
Cletus
The drill bits are genuine, made in USA and drill with beautiful even spirals of metal exiting the flutes. A thing to behold.
The tail stock has a Jacobs ball bearing Super-Chuck.
My 5C chuck is a Bison Set-tru and the 3-jaw is a Gator. Granted the 4-jaw is the original Grizzly, Chinese chuck but, since the parts get indicated with the DI every time it's used, it doesn't seem to be an issue.
That said, I've been looking at 6-jaws and the only thing that holds me back is a number of reports that the scrolls on 6-jaws are much finer than a 3 or 4 jaw and susceptible to being screwed up with a crash ( not that that would ever happen.) I'd appreciate any comments on this. Are 6-jaws that much more delicate? The Pratt-Burnerds and Bucks are quite lovely.
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If the caps were machined as integral parts of the frame they could be cut off with a slitting saw after, quite common to leave a gap between cap and frame and use nuts & studs to hold it in place and a lock nut so pressure on the beraing can be adjusted.
You have made a lot of good progress Stan.
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In rethinking my "plan" I believe the flaw is that both the pivot and the crank bearings would have to be bored extremely precisely in order to be parallel; else there'd be some binding.
My 1942 Monarch came with its original Cushman 6-jaw chuck, which is not at all delicate. It is marked so that it can be installed in the same D1-3 lugs each time; I assume it had runout measured and the orientation chosen to minimize runout.
One advantage with a 6-lug that I use frequently is that I can install two parallels across two different pairs of jaws, and then use them to insert a workpiece against their edges before tightening. The work installed this way then runs very true. It's very useful to remove the parallels before turning on the spindle, :hammerbash: The same work replacement accuracy or better can be done with soft jaws, but this is quicker. The parallel method needs a minimum work diameter for the parallels to fit and allow the jaws to close.
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I learned early on to remain clear of a path perpendicular to the chuck.
This was quite useful when I was using parallels, as KVOM describes, to set a part in the chuck.
I generally test a lathe setup by a quick press of the inching button. The parallel was launched across the shop and hasn't been seen since.
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Hi Stan,
Sorry I haven't commented long before now but I have been watching. Aluminum for all it's versatility is very unforgiving when it comes to tool marks. Even .001 shows up on a finished piece. I know that a .001 cut on brass and steel is still .001 but somehow it doesn't appear the same.
I'm proud of you my friend for the complex machining on the uprights. CNC is nice but I think there's more self satisfaction when complex parts are created by hand.
This engine certainly has a Victorian character and will be extremely attractive when finished.
Keep up the good work.
gbritnell
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Thanks, George. I truly appreciate the comments.
I'm pretty sure that between the various Cratex shapes for the Foredom and the abrasive sticks from the tool and die supply, I can get the interior smooth. It's only my time.
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Vern, thanks for setting me straight, musta been the "beer goggles". I actually was referring to the drill chuck, looked at first glance like the one that came with our lathes. You know, I have done a bit of turning and QC checking and the 3 jaw that came with our far eastern lathes is pretty darn good. It even impressed my BIL, and that's hard to do if it isn't something you would find in a die shop at a, say, GE plant in the 70's 8). Vern if I may: George I'm glad you weighed in here. I, just last night, via PM, told Stan that was some Britnell quality metal carving. He graciously laughed it off and said, " I only wish". George, you are an inspiration to all of here and Stan is proving that someone is working hard at showing it. My hats off and sincere thanks to the both of you :cheers:.
Cletus
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So, five months down the line since I've posted to this build log.
Getting ready for the American Precision Museum Show in Vermont, Thanksgiving in Florida, Cabin Fever, etc, etc, etc really stopped the postings. I've got every step documented and will post a log. If you've ever done one, you know that they are time-eaters.
That said, I've been punching the time clock in the shop most days when I'm not on the show circuit. :lolb:
It is a runner!! :cartwheel: :cartwheel:
Major thanks to KVOM for sending me his drawing of the port block. When he modeled this engine, he realized that the inlet and exhaust ports were too close to the channels and could possibly connect them. Exactly what I did. Using his drawings, I remade the port block.
I had spent a week screwing around trying to get it to run and then contacted KVOM.
Quickie first run here.
https://www.youtube.com/watch?v=GECvotQs11M
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It's about time. I've been wondering where you've been. ;D
Nice! Love the slow-mo! And with sound!
Coooooooool.
That's my slow-mo typiiiiiiiiing.
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Nice one. Who needs gaskets and screws? :cheers:
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Awesome Stan and congrats on the runner. I knew you were at it and glad to see it running. I'll be waiting for the finally............I...........like............ :Love:
Don
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She's a beauty Stan. Yeah, I have been wondering what you were up to as well....now we know :) Love the slow motion too!!
Bill
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And I thought you were just doing the South American show circuit :lolb:. Great job Vern.
Cletus
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Very nice Stan!
OK the vacation is over now it's time to catch up on your build logs.
Dave
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Thanks! The build logs will appear shortly.
This engine is, in terms of the precision of the parts, difficult.
The entire valve linkage mechanism (which I'm pretty sure was designed while quaffing multiple libations) goes like this: eccentric moves eccentric strap, which moves the slotted link on vertical, parallel rods. A piece which rides in the link slot, is connected to a rod which rotates and moves the valve link up and down. This link, which has a round end which fits into a slot on a part at the end of a threaded rod which is connected to the D valve in the steam chest.
You'll see.
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Lady Godiva Rides Again - Episode 4
Roy Ozouf’s Coventry Engine
Crankshaft
12L14 was used for this built-up crankshaft. The first op, after turning to diameter and parting to length, was milling keyways on each end of the shaft. Not quite sure why both ends have a keyway, as there is only one flywheel, but I’m just following the drawings.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-82.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-82.jpg.html)
Now, some layout for the cheeks. Note the exquisite, Cletus-made and hardened, punch.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-83.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-83.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-84.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-84.jpg.html)
Drilling and reaming followed
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-85.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-85.jpg.html)
Locating pins were turned for the rotary table
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-86.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-86.jpg.html)
Then, the ends were rounded.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-87.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-87.jpg.html)
And, connected
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-88.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-88.jpg.html)
A visit to Oliver was next to remove offending machining marks.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-89.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-89.jpg.html)
Next up is the cheek spacer
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-90.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-90.jpg.html)
Obligatory ½” micrometer shot
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-91.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-91.jpg.html)
Checking all dimensions carefully.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-92.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-92.jpg.html)
The two spacers. These are to give a heavier look to the crankshaft.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-93.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-93.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-94.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-94.jpg.html)
Everything fitted in position.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-95.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-95.jpg.html)
The side frames were aligned with dowel pins for drilling and line boring for the pivot shaft bearings
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-96.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-96.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-97.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-97.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-98.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-98.jpg.html)
Now, the holes for the crank bearings.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-99.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-99.jpg.html)
With that completed, I returned to the crankshaft. It’s held together with 4/0 taper pins and Loctite. The taper reamer is sized for the 4/0 pins.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-100.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-100.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-101.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-101.jpg.html)
After allowing the Loctite to cure overnight, the center was milled away.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-102.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-102.jpg.html)
After filing, another part is completed.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-103.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-103.jpg.html)
The crankshaft bearings were turned from bronze,
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-104.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-104.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-105.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-105.jpg.html)
Next up: The cylinder.
Stay tuned.
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That's an awesome runner Stan. Congratulations.
Vince
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Very nice Stan and I see you have adopted my tactic of making the engine then writing about it.
Thanks also for the slow motion as it allows the valve linkages to be seen in action.
I'd take a guess that the other keyway is there if you wanted to add a drive pully
J
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Thanks for the comments. Much appreciated.
Jason
About the drive pulley. I'm completely out of sewing machines. :ROFL:
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You have just got time to construct an ice cream maker ready for the comming show season ;) There was a guy in Australia who was casting some up at a suitable scale over on HMEM.
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Lady Godiva Rides Again - Episode 5
Roy Ozouf’s Coventry Engine
Cylinder
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Cylinder%20dwg.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Cylinder%20dwg.jpg.html)
I have a nice piece of 2”” Durabar cast iron. I got this from PhilJoe, who got the drop at at the Durabar facility near him. If you’re not familiar with this, here’s something from their website.
“Dura-Bar is an engineered iron that offers machining advantages over carbon and alloy steel as well as other continuous cast iron bars.
Dura-Bar is a highly machinable material. Continuous casting produces a product superior to castings made from the static casting method. The iron bars produced by the continuous cast method have a fine-grained, dense, as-cast structure. Since the bar is pulled from the bottom of the holding crucible, dross, slag and other impurities float to the top, away from the opening of the die - allowing for fewer defects and improved productivity. ”
The recessed curves were done with the Serepton Radius Tool. This was before I had gotten the Holdridge Radius Cutter from the used tool guy at the Vermont show. The Serepton is OK but not even in the same league as the Holdridge.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-106.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-106.jpg.html)
Then, step drilling and boring. I drilled until I could fit my thickest boring bar.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-107.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-107.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-108.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-108.jpg.html)
Then, to the Bridgeport to Flexhone the bore. I had two 1” Flexhones: 120 and 240 grits.
Lovely finish.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-109.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-109.jpg.html)
I needed to complete the pivot shaft since it must be in place to drill the cylinder intake and exhaust ports.
There is a through hole used for indexing. With a dowel pin in the hole, I indexed the part to zero in the spin indexer. This was done so that other holes could be drilled at required angles.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-110.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-110.jpg.html)
With that completed, the pivot shaft was affixed to the Pivot block which was affixed to the bottom cylinder cover. That assembly was bolted to the cylinder.
The Pivot shaft was positioned on a pair of 1-2-3 blocks in the vise. This ensures that the milled flat is parallel to the pivot shaft.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-111.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-111.jpg.html)
A test fit of the piece which will be the port block.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-112.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-112.jpg.html)
The port block, with holes and layout. This block was later remade based on KVOM’s drawing.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-113.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-113.jpg.html)
Then, the steam chest.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-114.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-114.jpg.html)
Corners rounded and complete.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-115.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-115.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-116.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-116.jpg.html)
Back to the Durabar for the cylinder top cover.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-117.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-117.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-118.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-118.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-119.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-119.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-120.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-120.jpg.html)
Another part finished
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-121.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-121.jpg.html)
After parting the cover, it was reversed and held in a 5C collet to machine the rear boss.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-122.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-122.jpg.html)
Family photo
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-123.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-123.jpg.html)
Piston
A simple turning. The piston has a centered recess for the taper pin which attaches it to the piston rod.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-124.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-124.jpg.html)
When I got close, much test fitting until I had a slightly tight sliding fit. Then, various grits of TimeSaver for the final fit.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-125.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-125.jpg.html)
Flats milled on the piston rod for adjustment.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-126.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-126.jpg.html)
Centered on the mill for drilling and reaming the taper pin through hole.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-127.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-127.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-128.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-128.jpg.html)
Next time: The Crosshead and Eccentric
Y’all come back.
-
The quality of the operations are only exceeded by the outstanding documentation :ThumbsUp: :ThumbsUp: Vern.
Cletus
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Thank you Cuz
Why not bring in the 2nd string grill guy for a few days and see it in person at NAMES? :LittleDevil:
-
Hi Stan, congratulations a nice runner. I do like the slow motion very much.
-
Thank you Cuz
Why not bring in the 2nd string grill guy for a few days and see it in person at NAMES? :LittleDevil:
That assumes Cletus is the #1 grill guy. :mischief: Still a good suggestion either way. I might even give him a ride on my way.
-
Stan,
Beautiful work on an interesting engine, congratulations :ThumbsUp:
Cheers,
Phil
-
:ThumbsUp:
I'm watching and enjoying my :popcorn:
-
Very nice work my friend!
Dave
-
Enjoying your write-ups, Stan, as always!
Very nice runner too!
Kim
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Lady Godiva Rides Again - Episode 6
Roy Ozouf’s Coventry Engine
Crosshead
The crosshead began with brass flatbar and round stock.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-129.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-129.jpg.html)
Everything was squared, drilled and fitted for silver soldering.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-131.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-131.jpg.html)
A form tool was shaped from ground O-1 tool steel and oil-hardened.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-132.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-132.jpg.html)
The crosshead top and bottom were turned with the form tool.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-133.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-133.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-134.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-134.jpg.html)
The corners of the body were turned round.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-135.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-135.jpg.html)
After parting off, the part was moved to the mill and indicated vertically.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-136.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-136.jpg.html)
Then, cut in half.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-137.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-137.jpg.html)
After attaching both halves with screws, the part was drilled and reamed.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-138.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-138.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-139.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-139.jpg.html)
The Eccentric
More bronze, turned and parted.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-140.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-140.jpg.html)
Centered on the mill with the Blake center point.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-141.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-141.jpg.html)
Then, the X axis was moved .109”, drilled and reamed.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-142.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-142.jpg.html)
The Eccentric Strap
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-143.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-143.jpg.html)
Laid out on .25” brass plate
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-144.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-144.jpg.html)
Locating pin and screws for the rotary table.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-145.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-145.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-146.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-146.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-147.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-147.jpg.html)
Some touchup and bolt recesses milled
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-148.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-148.jpg.html)
Then, cut in half.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-149.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-149.jpg.html)
Cylinder passages and other holemaking.
The port block and steam chest aligned
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-150.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-150.jpg.html)
Then clamped in position on the cylinder for drilling and tapping the attachment holes.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-151.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-151.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-152.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-152.jpg.html)
I decided to drill the air passages through the cylinder and port block. The drawings suggest spotting the port block in position, removing it and then drilling. This seemed like too much possibility for error. This way, I know that the passages are aligned perfectly.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-153.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-153.jpg.html)
Opening the admission/exhaust port.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-154.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-154.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-155.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-155.jpg.html)
Now for the bottom side passages
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-156.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-156.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-157.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-157.jpg.html)
Tapping the holes for the piston rod gland retaining screws.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-158.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-158.jpg.html)
The Ministry of Fiddly Bits returns in the next episode.
Thanks for tuning in.
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Beautiful work and documentation Stan. Can't wait to see if this sucker runs :lolb: Yeah I know its a retro log :)
Bill
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Awesome work and photos Stan. You are the man buddy........ :praise2:
don
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Great work Stan! :ThumbsUp:
Thanks for sharing :cheers:
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Good episode Stan. Looking forward to the Fiddly Bits, minister.
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Lady Godiva Rides Again - Episode 7
Roy Ozouf’s Coventry Engine
Fiddly Bits
The valve action has all manner of small parts which move in mysterious ways.
The rocker bracket was laid out with a print of the drawing.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-159.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-159.jpg.html)
After roughing it out with a jeweler’s saw, much sanding and filing followed. Here, the Foredom Flex shaft tool in it’s holder.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-160.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-160.jpg.html)
Then to Oliver
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-161.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-161.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-162.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-162.jpg.html)
A tube was turned down at one end to fit in the bracket hole for silver soldering.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-163.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-163.jpg.html)
Next is the rocker shaft. Again two parts to be silver soldered. First, the rotary table to round the ends.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-164.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-164.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-165.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-165.jpg.html)
The valve rod end first has a slot milled with a center-cutting end mill (.093)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-167.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-167.jpg.html)
Then to a square collet to round, drill and tap the other end.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-166.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-166.jpg.html)
The link, is another built-up part. It moves up and down on parallel rods which pass through the link guides.
Starting with a piece of brass flat bar, it was face milled to thickness.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-168.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-168.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-169.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-169.jpg.html)
Then, small recesses were milled to locate the guides for soldering.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-170.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-170.jpg.html)
Drilling and rounding.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-171.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-171.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-172.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-172.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-173.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-173.jpg.html)
And, slotted.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-174.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-174.jpg.html)
A bit of filing finished the link.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-175.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-175.jpg.html)
Starting with .25” brass square bar, the top was rounded.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-176.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-176.jpg.html)
Positioned for soldering
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-177.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-177.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-178.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-178.jpg.html)
Next, the guide rods. To ensure that they were the same length, I used the Cletus-built,close-enuf, bolt action tailstock stop. Amazing! It worked so well and was so much fun that, I couldn’t stop at the required two rods.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-179.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-179.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-179.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-179.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-181.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-181.jpg.html)
Then the tiny, threaded brackets for the guide rods. First, milled, then cut.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-182.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-182.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-183.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-183.jpg.html)
Two extra (just in case I did a Bozo op)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-184.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-184.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-185.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-185.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-186.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-186.jpg.html)
The brackets, guide rods and link, screwed to the side plate.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-187.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-187.jpg.html)
Drilling the steam chest, gland mount.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-188.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-188.jpg.html)
In position with working hardware.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-189.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-189.jpg.html)
I though I’d start with a large chunk of brass for the valve as it’s easier to hold.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-190.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-190.jpg.html)
Milled and cut off.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-191.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-191.jpg.html)
And, in position
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-192.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-192.jpg.html)
Now, onto the rocker arm, laid out and screwed to the rotary table.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-193.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-193.jpg.html)
Cranking the table around to the layout lines
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-194.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-194.jpg.html)
And the, addressing the sides
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-195.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-195.jpg.html)
The arm had a turned boss. I turned a tiny faceplate, screwed the arm at center and melted some Crystalbond to hold the part.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-196.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-196.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-197.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-197.jpg.html)
Beginning the assembly. Now it may be easier to see how the valve motion works. The part not shown is a “die block” with floats on the rocker arm and travels in the link slot.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-198.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-198.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-199.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-199.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-200.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-200.jpg.html)
Next, smoothing out the side plates and the flywheel.
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Man, you hit the fiddly bit jackpot with this update Stan. Nice work though all the way around.
Bill
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Awesome Stan! I just love all the setups. You sure hot the jack pot this round......... :ThumbsUp:
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I'm amazed at all those little tiny parts Stan; you are going after it like an old pro!
Great pictures, machine work, fabrication, set ups, and wonderful results.
I haven't had a chance to use my Close-enuf, bolt action tailstock stop yet; but I'm looking forward to be being able to put it to good use.
Nice work!
Dave
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Vern, you're spinning that RT like Wolfman Jack did a turntable. All around great craftsmanship. It is a joy to use a fine handmade tool, now isn't it :lolb:
Cletus
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More teeny, tiny, little parts. :insane: Amazing how ya'll make those. The biggie for me on this page is the...
Bolt Action Stock Stop Cleat(us) Never seen the likes of that before and it's now part of my gonna do it list.
Pete
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That's a fine update Stan! Thanks for all the pictures & explanations.
I had to go back and watch it run again to see all the fiddly parts moving and I'm still not sure how they're all connected. Do you have a few more fiddly parts to go? I didn't see the thing that connects the valve rod rocker to the yoke/link gizmo. Have you showed us that part yet?
Just fascinating!
Kim
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Kim
To be honest, I didn’t completely understand the valve motion and the part interactions untilI assembled the engine.
I realized I had no pictures of the die block which connects the rocker arm to the link.
The only thing to do was to boot the Mac into Windows and fire up Inventor.
Hope this helps
The die block
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-202.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-202.jpg.html)
The die block inserted into the rocker arm.
A 2-56 nut holds it together and the die block is free to pivot as it travels within the link slot
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-203.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-203.jpg.html)
The complete sub-assembly
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-201.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-201.jpg.html)
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Thanks Stan, that helps a lot! Even I could follow that description! Loved the renderings :)
This is really a fascinating (maybe even overly complex) set of motions to move the valve. Was this a real engine? It is just amazing to watch.
Sorry, I didn't mean to call you out on the one part you didn't show. I just figured that I'd missed it, or that it was still to come!
Thanks for the detailed explanation Stan!
Superb build log, as always!
Kim
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Lady Godiva Rides Again - Episode 8
Roy Ozouf’s Coventry Engine
Control Tower
The drawings show an air control valve stand. They also say, “see text.”
Roy must have decided that if you’ve gotten this far, you don’t need no stinkin’ text as it does not exist. It is pretty straightforward so off I went. I did make some changes to thread sizes, etc. based on the taps, dies and brass stock I had on hand.
The drawing shows the body turned from a 1” diameter brass round. Since the only thing that is 1” is the ⅛” base flange, it seemed like a lot of brass was going to be converted to chips. I decided to make the body in two parts: The flange and the upper body.
A .625 brass round was turned to shape.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-212.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-212.jpg.html)
Then. reversed, drilled and tapped.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-213.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-213.jpg.html)
Next, two bosses to be drilled and tapped ¼-40. These will be soldered into the body.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-214.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-214.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-215.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-215.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-216.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-216.jpg.html)
With those completed.the body was moved to the mill, spot faced and two .25 holes were drilled 90º apart.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-217.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-217.jpg.html)
A dry fit.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-218.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-218.jpg.html)
Next, the plug. This was turned and parted off.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-219.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-219.jpg.html)
Then, two intersecting holes were drilled 90º apart to align with the holes in the body.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-220.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-220.jpg.html)
Rummaging through the brass box, I located a cutoff that had the correct dimension for the base flange. Turned per the drawing.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-221.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-221.jpg.html)
Moved to the mill for a bolt hole circle for mounting bolts.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-222.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-222.jpg.html)
The shaft nut was turned from a brass hex, shaped and threaded.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-223.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-223.jpg.html)
A family shot.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-224.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-224.jpg.html)
One more part for the valve. The drawing has this machined from solid. I wasn’t thrilled with the look of the part. My version follows.
Starting with a 1” brass round.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-204.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-204.jpg.html)
I need a .75” bore. Step drilled up to a Silver and Deming bit slightly under .75.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-205.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-205.jpg.html)
Then bored to diameter.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-206.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-206.jpg.html)
I wanted to maintain a .125 wall thickness. In order to measure accurately, a ball was installed on the micrometer. This adds .200 to the measurement.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-208.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-208.jpg.html)
Then the wall could be measured. So, .3251-.200=.1251. Close ‘enuf.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-207.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-207.jpg.html)
Moving the part to the mill, 4 holes were drilled around the perimeter. 90º apart.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-209.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-209.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-210.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-210.jpg.html)
A form tool and files shaped the edge.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-211.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-211.jpg.html)
Another brass round, center drilled, 4 holes on the perimeter and the center hole filed square.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-225.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-225.jpg.html)
Then 4 precisely equal length brass rods.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-226.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-226.jpg.html)
So, we end up with this collection of parts.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-227.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-227.jpg.html)
When assembled, make a hand wheel for the valve.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-228.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-228.jpg.html)
They will be soldered tomorrow followed by filling, polishing, etc.
The body and base flange needed to be soldered. I had been thinking about using Tix solder. It has a low liquidus temperature (275º F/135ºC) and a tensile strength of 4000 PSI. After cleaning all of the parts and applying Tix flux, I cut small pieces of the solder and put the assembly on a hotplate. Two minutes later, the solder melted and flowed beautifully through all of the joints. No torches, no melted brass.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-229.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-229.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-230.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-230.jpg.html)
Paint is next, then the base. Stay tuned.
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Nice episode Stan.
You mentioned stepping up in drill sizes. Having just had another bad time with big drills...in what increments do you step?
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Zee
I did ¼, 3/8, ½, 5/8 and .73.
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Nice work on that Stan. It turned out beautifully. I like that little handwheel also. Good to see an update on this build.
Bill
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Nice results Stan and the handwheel turned out great. Anxious to see it after sliver soldering. If you remember when I made my handle I used five parts to build it up also.
Don
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Nice update Stan!
Good to see you back at it!
Dave
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Very nice work Stan!
Kim
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Hi Stan, nice update and some interesting parts. I like the soldering
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Vern, beautiful fab work. I really like the hot plate method :ThumbsUp: :ThumbsUp:. I was thinking though, you really ought to turn the heat up and ditch the sweater 'fore you get hung up in something or catch on fire :lolb:
Cletus
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Thanks, guys. Much appreciated.
Hey, Cletus! That's my LL Bean, Machinist Model, lucky shop sweater. The shop stays at 70°F year round but if I don't wear the shop sweater, I muck up parts. The sleeves push up nicely when I'm at the lathe.
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Good tip on the Tix flux/solder. I'm going hunting for some. :ThumbsUp:
Nice work on the valve too.
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Here you go
https://www.riogrande.com/Search/Tix
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Order in!
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I've used the Tix solder for many years on scale ship models, more recently on clocks and engines. Fine for parts that dont get much heat, quite strong, flows into tight joints very well. Be sure to get a bottle of thier flux to go with it. You want to be sure to wash off the parts well after use, or the flux will start to etch the metal over the next day or so. It is not very strong on joints with a gap - you can put in enough to fill a gap, but it will not be very strong. It seems expensive, but if used on tight joints it takes very little, so it goes a long way.
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Incredible ingenuity with ways of holding things! I think I've got two choices - watch and learn or give up. Could go either way.....
Forgive my ignorance, but what on earth is Crystalbond? Never heard of it. And is the little block with collets a home-made item? I can see its a must-have for a mill.
John.
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Yes, parts that get hot would be an issue and could prove entertaining. Since my small engines run on air and this part is only an air valve, I was quite OK with the Tix. I did a test solder and wasn't able to twist the parts away or break the joint. The two bosses are .25 OD and the hole to receive them is .251. The solder wicked all the way through.
John
The collet blocks are indispensable. They generally come in a set. One square and one hex with nuts and wrench. Actually one of the less expensive add-ons.
I did a post on this forum about Crystalbond. IIRC It was titled "Magic Sticky Stuff". A quick search should turn it up. Just another in the "How in the hell do I hold this part?" bag of tricks.
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John
Here you go
http://www.modelenginemaker.com/index.php/topic,4711.msg88782.html#msg88782
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Thanks for the info Stan. I'll do some looking.
Best regards,
John.
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5C collet blocks will get a lot of use. Note that the set usually doesn't come with a pin wrench for tightening the nut, so order one with it. They do come with a cam-operated nut, but I found this generally useless. Of course you also need a set of collets to use with the blocks.
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Kirk
Absolutely correct. I had forgotten that I had ordered a pin wrench separately. Also, the cam lock thing :ThumbsDown: :ThumbsDown: :ThumbsDown:
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Sub-Episode
Today's progress. Soldered the Hand Wheel followed by copious sanding, filing, buffing, polishing and general mayhem.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-231.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-231.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-232.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-232.jpg.html)
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That handwheel turned out very nice. I can imagine the cleaning up and filing and polishing work though. Well done!!
Bill
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5C collet blocks will get a lot of use. Note that the set usually doesn't come with a pin wrench for tightening the nut, so order one with it. They do come with a cam-operated nut, but I found this generally useless. Of course you also need a set of collets to use with the blocks.
I've never used them before, but those collets/blocks look very handy. Do the different sizes handle a range of stock, or just that nominal size? Looks like they come in sets with different increments from one size to the next, any tips on choosing? Any brands to avoid?
Thanks!
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They accept 5c collets. Any size or shape 5c collet wI'll work. I would think Sherline or someone would make them for the other size collets also.
Cletus
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My 5C set includes imperial sizes by 16ths. Largest size is 1-3/16". Largest size that stock can go completely through is 15/16". Of course they make metric sizes as well as square and hex collets. I have bought a couple of these special collets over time, such as a couple of square sizes. These are mainly for use on the lathe where I have a collet chuck.
It's not a good idea to vary stock size by more than +/- a couple of thou from the nominal size of a collet.
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My 5C set includes imperial sizes by 16ths. Largest size is 1-3/16". Largest size that stock can go completely through is 15/16". Of course they make metric sizes as well as square and hex collets. I have bought a couple of these special collets over time, such as a couple of square sizes. These are mainly for use on the lathe where I have a collet chuck.
It's not a good idea to vary stock size by more than +/- a couple of thou from the nominal size of a collet.
Gotcha, so sounds like they are great for the raw bar stock, maybe not for turned parts that are in between nominal sizes. Look very handy for a lot of things. Thanks!
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I've got a set by 1/32" in round. Also square and hex by 1/16"
The 5C collet chuck is on the lathe 90% of the time. I do keep a few emergency collets (undrilled) for odd sizes.
Many of mine are Hardinge (eBay). New ones, I generally get Lyndex-Nikken.
Scott Nelson's( Cheepo45) shop at U. Delaware has a complete set of 5C. Letter, number and fractional sizes for the HLV-H(drool)
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If I was going to dream and wish for the ultimate shop accessory, it would be a complete set of every kind and size of 5c collet know to man in an antique oak case. And whilst dreaming, it would be really sweet if they were all within +/- .0001" runout :facepalm:9
Cletus
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5C collet blocks will get a lot of use. Note that the set usually doesn't come with a pin wrench for tightening the nut, so order one with it. They do come with a cam-operated nut, but I found this generally useless. Of course you also need a set of collets to use with the blocks.
I've never used them before, but those collets/blocks look very handy. Do the different sizes handle a range of stock, or just that nominal size? Looks like they come in sets with different increments from one size to the next, any tips on choosing? Any brands to avoid?
Thanks!
Chris,
Have you seen this website for after market Sherline ER collet headstocks and collet systems: http://www.sherlinecollet.com/index.htm
Looks like money will solve the problem.................lots of money! :shrug:
Jim
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5C collet blocks will get a lot of use. Note that the set usually doesn't come with a pin wrench for tightening the nut, so order one with it. They do come with a cam-operated nut, but I found this generally useless. Of course you also need a set of collets to use with the blocks.
I've never used them before, but those collets/blocks look very handy. Do the different sizes handle a range of stock, or just that nominal size? Looks like they come in sets with different increments from one size to the next, any tips on choosing? Any brands to avoid?
Thanks!
Chris,
Have you seen this website for after market Sherline ER collet headstocks and collet systems: http://www.sherlinecollet.com/index.htm
Looks like money will solve the problem.................lots of money! :shrug:
Jim
Nice stuff, but you are right, very pricy! I was thinking of the collet blocks for workholding in the mill, primarily.
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That's All Folks
After cloistering myself in the shop for the last few weeks, I’m calling the Coventry “Close ‘Enuf”
I’ll be packing it up for it’s trip to N.A.M.E.S. next week.
The Coventry was not an easy build for me. Sure making the parts was straightforward: One part at a time and pretty soon you have enough parts for a running engine. The sticky part is the the mechanism for the valve movement has many parts that all are moving in concert and in different directions and on different planes. Throw in a variant of a Scotch Yoke and the timing is very, very particular. I had removed and replaced the steam chest cover so many times while setting the timing that I finally made a Plexi cover.
The air intake is plumbed under the base and up through the ceramic tile. I’ve gotten quite proficient at using a diamond core drill on the tile: I’ve also got a nice collection of broken tiles in a box.
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-233.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-233.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-234.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-234.jpg.html)
(http://i1126.photobucket.com/albums/l604/sshire/Coventry%20engine/Coventry-235.jpg) (http://s1126.photobucket.com/user/sshire/media/Coventry%20engine/Coventry-235.jpg.html)
The next project begins as soon as I’m back from N.A.M.E.S.
I’m quite sure that you’ll be quite thrilled to see yet another Monitor build.
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Simply lovely Stan, great thread to follow buddy. I just love all those excellent photos through the whole process.......... :praise2:
8)
Don
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It's a beauty Stan.
Video on its way?
Wish I could be there at N.A.M.E.S.
Probably once I retire. Oops...there it is again.
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Congratulations Stan! You've made a beautiful engine. Wish I could see it at Names, but that's certainly not in the cards for me. Many people will enjoy seeing it though, you can be sure of that!
I'll enjoy another Monitor build! May even do one myself someday. Can't have too many engine build threads :)
Kim
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Oh I missed that part. Thinking of a Monitor Stan?
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Thanks everyone.
Zee
The metal is in the shop. Drawings printed large. Recipes ready in the kitchen.
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Thanks everyone.
Zee
The metal is in the shop. Drawings printed large. Recipes ready in the kitchen.
The Coventry came out awesome!
And another Monitor to watch - excellent!! :popcorn:
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Let's see...that makes 4 Monitors, no?
Mine. Started long ago, yet to be completed.
Chris. Started and completed.
Bruce. Started and no doubt will be completed before mine.
Stan. Yet to start but no doubt will be completed before mine.
Sigh.
Hm...Seems like there's one or two other people thinking about this engine.
Kudos to Julius. He's got to feel pretty good about this.
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Beautiful engine Stan!
Looking forward to seeing in it person next week.
Dave
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Lovely job Vern :ThumbsUp: Monitor eh, wouldn't be influenced by the planned equipment purchases would it :stir:
Cletus
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That sure turned out nice, Stan. :ThumbsUp: :ThumbsUp:
Looking forward to the monitor build.
Joe
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Well damn, Cletus. I don't see how the new set of open end wrenches in 1/32" increments will help :lolb:
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Hi Stan, a nice engine and proper made build log with excellent pictures. I like the Plexi cover, it is always nice to see what is going on there inside and to what the motion.
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Great description of your build of a beautiful and unusual engine.
I am inspired!
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Just re-read this whole thread, and I am still inspired!