Author Topic: Quarry Bank Mill Engine  (Read 1641 times)

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Quarry Bank Mill Engine
« on: December 16, 2018, 03:42:39 AM »
This is the engine that I will be trying to build here.  This is a "wall engine" or maybe a "ceiling engine" that is displayed in the Quarry Mill Museum.  I have never been there but the picture appearing in John's Textile Mill Diorama provided by member, deltatango, gives enough information to go by.  Stew Hart has also modeled this engine and provided plans that others have used to build from. Julius has also prepared detailed plans based of Stew's plans and they will also be referred to at times but these are all METRIC and that is difficult for me. I need to work in inches and pounds and hours and minutes and degrees so I will make my own set of plans in those terms.  Oh, wait, I guess I will have to use decimal inches rather than fractions but I will work in Imperial Time Units.


i get as much fun from the design process as I do from the build anyway so mostly what I need is a few starting dimension and the rest of the design has to follow.  Tools and available material plays a big part.  For cylinders, I like brass or cast iron and If I use brass, the cylinder will probably be about 1 inch diameter and less than 2 inches long.  I want to use aluminum as much as possible for the stationary parts and if I can't get ahold of a big enough piece of aluminum for the engine block, I will build it up from bar or plate.


I also enjoy trying to get in the head of the original designer as much as possible and try to understand the the conditions and limitations that he had to work with.  For example, this engine needed to be compact due to the limits of space. It was intended to hang on a wall or from overhead beams.  Not only did it not get its own building as did many steam engines, it didn't even get it's own floor space.  i also suspect that the reason for the twin cylinders was to provide smooth, high speed without needing a large flywheel.


The overcrank provides a very compact engine with the crankshaft in the center of the plan and the overall length is mostly within the diameter of the flywheel.  So why the angled mounting of the valve chest on top of the cylinders.  Again, I suspect that the reason is space. The valves are mounted on top of the cylinders to keep the engine as narrow as possible. By placing the valves in the same chest, piping is simplified and so is control. Steam pressure is controlled for both cylinders with a single governor. 


The angle of the valve chest is to keep the valve rods axis in line with crankshaft. Any other arrangement would need some kind of crank lever mechanism to have equal valve motion. But why a 15 degree angle?  Why not 23 degrees or 12 degrees? Again it might be space. A shallower angle like 10 degrees would require that the crankshaft be further from the cylinder block while a steeper angle like 20 degrees would move the crankshaft and the cylinders closer together.  That, however could cause interference between the cranks and the cylinder rod end. And it is easier to manufacture to a common angle than to something like a 23 degree slope, so 15 degrees.


All the rest of it just follows from those basic parameters.  I use Alibre' because it is what I have.  I have used it for so long that I don't have to think about it.  I have a free license that is more than 10 years old and I can't upgrade without buying a new PC so that is what it is.  The only problem is that I have used it for so long that I am about out of disk space.  I'm going to have to find some way to offload a bunch of older design files and photographs of engines, kids, boats, and horses, and dogs.  I also need to relearn all of the procedures for uploading designs, photos, and videos to the forum.  I seem to have forgotten a lot of that.
« Last Edit: December 16, 2018, 03:51:54 AM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #1 on: December 16, 2018, 04:03:07 AM »
And here is where I am in the design process.



« Last Edit: December 16, 2018, 04:08:57 AM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline deltatango

  • Full Member
  • ****
  • Posts: 166
  • Melbourne, Australia
Re: Quarry Bank Mill Engine
« Reply #2 on: December 16, 2018, 05:44:21 AM »
Hi Captain Jerry,
Here is a more detailed picture of the little engine at Quarry Bank Mill that I didn't put in the earlier post:



Hope this helps!

Regards, David

Offline 10KPete

  • Full Member
  • ****
  • Posts: 1483
  • Nordland, WA, USA
Re: Quarry Bank Mill Engine
« Reply #3 on: December 16, 2018, 05:55:28 AM »
Most interesting! A Fenner Power Twist 'tween the 'gin and shaft! And a Browning pulley on the gin.....

Beautiful machine.. :Love:

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.

Offline sbwhart

  • Full Member
  • ****
  • Posts: 694
  • Live Long and Prosper
Re: Quarry Bank Mill Engine
« Reply #4 on: December 16, 2018, 07:26:28 AM »

The angle of the valve chest is to keep the valve rods axis in line with crankshaft. Any other arrangement would need some kind of crank lever mechanism to have equal valve motion. But why a 15 degree angle?  Why not 23 degrees or 12 degrees? Again it might be space. A shallower angle like 10 degrees would require that the crankshaft be further from the cylinder block while a steeper angle like 20 degrees would move the crankshaft and the cylinders closer together.  That, however could cause interference between the cranks and the cylinder rod end. And it is easier to manufacture to a common angle than to something like a 23 degree slope, so 15 degrees.



When I first drew this engine up the 15 degree angle was just a guess as I couldn't get direct access to the original to measure it up despite asking Quarry Bank if I could, I just couldn't get it through to them what I wanted to do  :cussing:  :- 15 degrees looked about right and it fitted in nicely with the rest of the geometry.

Stew
A little bit of clearance never got in the way

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #5 on: December 16, 2018, 02:18:03 PM »
Thanks to all of my old friends who have welcomed me back to this group. It feels good to do something creative and it is even better to have a group of people like you who are so willing to share your skills and experience. I beginning to get more comfortable in the shop but I still have a few things to remember, like wear overalls in the shop and leave them in the shop, brush your hair and wipe your feet well before coming in the house, find other things to talk about at the dinner table.


David: The better photo that you posted is very helpful. The sharper image makes it easier to work out some of the detail but as usual, more information means more questions which I will ask when I get to them. Thanks. If you have a wider shot that shows home the engine is mounted I would be interested.


Stew:  Thanks for looking in.  I am sure that everyone looks to you as the expert on modeling this engine. I have a hot key on my computer that takes me to your Madmodder build and I go there frequently.  I am going to move as quickly as I can with this project for many reasons and I want to finish it within a year. I will try to post updates as often as I can so if you see me headed down a dead end, I would welcome a "heads up."

There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Gas_mantle

  • Full Member
  • ****
  • Posts: 1236
  • North Yorks - UK.
    • My Youtube channel
Re: Quarry Bank Mill Engine
« Reply #6 on: December 16, 2018, 05:06:07 PM »
Jerry, I look forward to seeing how your build goes.

I've always liked the unusual style of this engine and did consider making one after I finished Stews' Potty Grasshopper, when I later studied the plans I thought it was a bit beyond my capability but it is still on my to do list.

 :popcorn: :popcorn:

Offline deltatango

  • Full Member
  • ****
  • Posts: 166
  • Melbourne, Australia
Re: Quarry Bank Mill Engine
« Reply #7 on: December 16, 2018, 10:12:38 PM »
Sorry Jerry, I only took the two pictures of the overcrank engine. I may be in the area again Sept/Oct next year and can visit QBM and take lots more but:
a) this isn't certain and
b) you'll have the engine finished by then anyway  :)

David

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #8 on: December 17, 2018, 04:09:20 AM »
David: Don't make the trip just for me.  But if you find yourself in the area....  I was only curious about the mounting. It won't change how I do anything.  Some of the detail that I have discovered examining your photo are more interesting.  The black paint makes it difficult to pick out but there seems to be some kind of spigot on the top of each cylinder, plugged with a square headed bolt.  Some kind of drain or bleed I guess.  By "top" I mean the side facing us.

I also notice that on top of the inlet valve it looks like some kind of hose barb.  Do you think it might have ever run on air or is that some kind of British steam fitting that I'm not familiar with.

Jerry
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 6112
  • Surrey, UK
Re: Quarry Bank Mill Engine
« Reply #9 on: December 17, 2018, 08:06:21 AM »
One of Stew's photos shows what looks to be a steel braided hose attached probably with a quick connector, as to whether it has steam or air I can't say. There is a small handwheel on the vertical shaft coming out of the top of the valve presumably to control flow into the valve chest.

Possible air run for demos in the mill as there may no longer be a steam supply plus it saves a lot of red tape.

Offline sbwhart

  • Full Member
  • ****
  • Posts: 694
  • Live Long and Prosper
Re: Quarry Bank Mill Engine
« Reply #10 on: December 17, 2018, 09:04:45 AM »
One of Stew's photos shows what looks to be a steel braided hose attached probably with a quick connector, as to whether it has steam or air I can't say. There is a small handwheel on the vertical shaft coming out of the top of the valve presumably to control flow into the valve chest.

Possible air run for demos in the mill as there may no longer be a steam supply plus it saves a lot of red tape.

We're about 45 minutes from Quarry bank and visit quite regularly for a walk around the woods to the Manchester airport viewing area, my wife loves watching planes taking off and landing. The museum has a good cafe that do excellent cakes and I take the opportunity to view their other engines running on steam, but they run over crank on air probably because the boiler is some distance away from it.  By the way this type of engine is also known as a "Return Crank.

Cheers
Stew
A little bit of clearance never got in the way

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #11 on: December 17, 2018, 10:26:59 PM »
I thought air for demo display might be the case. I have never seen the inside of a steam driven mill.  In the Carolinas, where I used to live, there were all sorts of mills, sawmills. furniture mills, and textile mills. There are even a few foundries.  I was in most of them but seldom got past the purchasing offices.  Sometimes I got to the tool rooms.  My employer manufactured power tools that were sold to the mills through local mill supply houses so I was there mostly to promote brand recognition.


I am beginning to understand that these small engines were ceiling or wall mounted to be close to the line shaft that they drove.  But what was under them?  Was there a drip pan for oil? Where did the exhaust go?
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 6112
  • Surrey, UK
Re: Quarry Bank Mill Engine
« Reply #12 on: December 18, 2018, 07:13:32 AM »
It's worth noting that Stew saw this engine in a separate workshop so it may have been a long way from the main boiler that powered the mill engines and their shafting. Quite possibly had a smaller boiler for the workshop which has not been restored if it even exists hence the use of air.

Exhaust may have gone back to a blast pipe to help the chimney draw or could simply have gone out the nearest wall, can't see them using a condenser or oil separator on it.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Shop Engine
« Reply #13 on: December 18, 2018, 02:43:06 PM »
I have just been looking at the engine and not fully understanding it's use.  Of course it is not a "mill" engine as I usually think of mill engines. It doesn't have enough power to drive the textile machinery.  It is used to power the tools in the workshop.   Looking at the pictures, it is clear that Stew's photo is from the opposite side as David's but still the same site. b


Not to be picky but the valve doesn't look right.  It is on top of the engine where it would be difficult to reach.  I think that valve was put on the engine sometime after it's life in the mill shop.  I think Stew's valve is a much better representation of the original arrangement. So why a governor on a small shop engine?  Because any steam engine really needs a governor.  We shouldn't just think of a governor as a speed control when it is really a power control. How does your mill react when you take a big bite with a roughing end mill? It depends on the built in electronic speed controller to goose up the power just as a governor on a shop engine needs to goose up the power when the table saw rips into a 4" beam.


Stew's nice little governor fits the bill nicely.  Nicely designed and positioned so that it is effective whether the engine is wass mounted or displayed flat.  I may not get to the governor but I will put a drive pulley on the shaft, just in case.


In light of all this, I am changing the title of this thread.
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline crueby

  • Full Member
  • *****
  • Posts: 7478
  • Rochester NY
Re: Quarry Bank Mill Engine
« Reply #14 on: December 18, 2018, 03:11:53 PM »
For those that have been there - do you know what the big handwheel on top of a (I assume) a valve is down at waist height to the left of the engine? Could that have been the original steam supply valve to the engine, before it was switched to air? Seems quite large...   :shrug:

Offline sbwhart

  • Full Member
  • ****
  • Posts: 694
  • Live Long and Prosper
Re: Quarry Bank Mill Engine
« Reply #15 on: December 18, 2018, 08:42:58 PM »
These small steam engines were used as you would an electric motor today to power all sort of machinery, my model horizontal mill engine that a few of you have built is actually based on a small mill rite's engine that's on display at the Northern mill engine societies museum at Bolton thia engine would sit on top of your desk they would move it about to wherever they needed power such as the re-boring of a large mill engines cylinders.

Any way these are all my old photographs i took of the over crank including some of the machinery it was powering.

I don't believe the engine was originally at Quarry Bank I suppose they found it some ware and decided  it would make a good display for the museum.

















Stew




« Last Edit: December 18, 2018, 08:48:50 PM by sbwhart »
A little bit of clearance never got in the way

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #16 on: December 19, 2018, 12:56:15 AM »
I sorted out how to assemble the block from aluminum bar stock but my regular camera was dead and the only camera I had was my phone.  I got a few shots of the results but I have never uploaded to the forum from my phone so this is sort of a test.  I was able to upload as an attachment but I was not able to imbed it in the text. That's something I will have to work out.

In the photo, it looks a little strange.  The loose aluminum block on top will be joined to the rest of the assembly and will be milled to the angle required for the valve chest. I have left it loose to make it easier to route the steam passages (I think) without having to plug holes later. Those details are being worked out now. 


The lower block looks like a single piece but it is assembled from four pieces of 1/2" thick aluminum bar that will be glued with steel filled two part epoxy (JB Weld).  I have had both good and bad experience with this product.  I think you should buy a fresh supply for a critical application like this.  Don't use the half used tubes that have been in the drawer for 6 months, and be sure to mix it thoroughly. I may reinforce the assembly with screws but if I do I will wait until the epoxy has cured for a couple of days and I will use brass screws just incase I drill into one as I go further.
« Last Edit: December 25, 2018, 01:57:08 PM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline deltatango

  • Full Member
  • ****
  • Posts: 166
  • Melbourne, Australia
Re: Quarry Bank Mill Engine
« Reply #17 on: December 19, 2018, 03:49:14 AM »
Hi Chris,
I don't think that the very large valve you asked about is anything to do with the display of a millwright's workshop, it's bigger than the engine and outside the display area. I can't remember anything about it from my visit.

David

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #18 on: December 19, 2018, 08:11:06 PM »
Hi Stew:


Thanks for the additional pictures.  The second picture has made me realize that I had the proportions all wrong.  I have the cylinders too far apart.  Not sure why but it may have to do with a wrong starting point in my planning, but it seems that the cylinders should be closer by 3/4 of an inch.  My error would have been more apparent if I had started my planning with the crankshaft.  My present spacing puts way to much unnecessary spacing.


I am going to attempt a heroic save of the cylinder block above.  These things seldom work out well so I am prepared to scrap this and start over.


Jerry

There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Tennessee Whiskey

  • Full Member
  • *****
  • Posts: 3681
  • Springfield, Tennessee. USA
Re: Quarry Bank Mill Engine
« Reply #19 on: December 19, 2018, 08:24:22 PM »
Iíll catch up on the build later, but, for now Iíd just like to welcome you back to port Captain  8). I hoped you hadnít been lost at sea. You have any equine stock now? Iíll be following along on this voyage for sure.

ATB,
Whiskey

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #20 on: December 21, 2018, 11:24:33 PM »
Hi Whiskey.  Thanks for the shout.  Trying to get back into the swing of things. My animal buddies are just a couple of dogs these days.  All the horses have been moved out to my daughter's training center where there is a lot more space and help to take care of them.  I lost a coupe of my dog buddies this year.  One of them had been suffering from spinal problems from the day we found him.  Not sure if it was a birth defect but I suspect it was from abuse and neglect,  He had good days and bad and one morning he didn't show up for breakfast.  I found him where he had dragged himself under the bushes behind his house. Live but tired of living, his back legs completely paralyzed. I spent the day with him but the next day we had to help him leave.  His sister had been suffering for several years with general poor health.  After her brother died she gave up too.  She would not eat and then she would not get out of her bed in the barn.  Within a few weeks, she was gone too.


I think I have one more project in me so drop in when you ge a chance.  I've got a lot of reading to catch up on too,


Jerry
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Online Dave Otto

  • Full Member
  • *****
  • Posts: 3439
  • Boise, Idaho USA
    • Photo Bucket
Re: Quarry Bank Mill Engine
« Reply #21 on: December 22, 2018, 01:29:25 AM »
It is rough to say good by to your friends, but at least you can rest easy knowing that you  gave them the best life that you could.
Sorry to hear Jerry, its never easy.

Dave

Online steamer

  • Global Moderator
  • Full Member
  • *****
  • Posts: 9652
  • Central Massachusetts, USA
Re: Quarry Bank Mill Engine
« Reply #22 on: December 22, 2018, 02:33:58 AM »
Ahh man   sorry to hear that Jerry, it's never easy letting them go.

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #23 on: December 22, 2018, 02:45:39 AM »
As I expected, my heroic effort to save the cylinder body fabrication failed so it is a do over.  I was prepared for it and it gave me a chance to get a couple of "i know better than that" mistakes out of the way. It also gave me a chance to devise a new or different way to preserve a center position.  Twice, in my earlier effort I meant to reach for the drawbar wrench to change tools and instead, grabbed the vise wrench and loosened the vise.  An old man working on auto pilot or hurrying to much. I lost the center for the cylinder bore and it had been a long process to find it the first time. My solution is to center drill a location that is a known distance along the Y axis from the cylinder center.  I can take the part out of the vise and put it back and then locate the drilled position then shift right or left along the Y to find my location.  I am using boring head in the mill to bore for the add on cylinder.  I chose the location for my witness mark to .495" from the actual center soit will be removed by the counterbore for the cylinder flange.  I think that will be shown in one of the picture att

Oops, battery failing. I will finish this post when I find my charger cord.

« Last Edit: December 24, 2018, 02:25:17 PM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #24 on: January 02, 2019, 05:27:56 PM »

I hope everyone enjoyed the holidays.  Lots of family time, not much shop time but now back at it.  I am slowly remembering things that I thought I new.  For example, converting someone else's metric plans to imperial is more than just converting mm > in.  Once you change a critical dimension to standard sizes and eliminate rounding, everything else is up for grabs, and if you also make a change to allow for available material, you might as well start from scratch.


The holidays did allow me some late night design time after everyone else was in bed so I have come up with this as a model within the range of my equipment and experience. I still need to design some of the finer details but this is a working video is what I am going back to the shop with.   


I am aware that the valve timing on the right hand cylinder is out of sync but that is easier to adjust in the shop than it is on the computer.

The valve cover is slid off so I can check the action.


« Last Edit: January 06, 2019, 12:47:28 PM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #25 on: January 08, 2019, 04:14:13 AM »
Progress report:


I am making headway on this project but my reporting efforts have been poor.  Partly because I seem to have difficulty sticking to a plan of action, and partly because I have not yet been able to work out a simple method of inserting pictures within the text so I am stuck with using attachments which make it difficult to follow.  Another problem is that this computer, which has more disk storage space than I ever thought I could use is now full of thousands of family photos, CAD files,and other things that I can not bring myself to delete So I am battling a serious problem with creating new designs and processing photographs.


But stick with me if you can. I will get better, I hope.  The first attached picture is the condition of the cylinder assemble as of now.  It is mostly assembled from aluminum bar, which I had on hand.  The cylinders are from cast iron bar.  This will be filled and painted to hide seams and joints so that I can pass it off as if from a single casting. 


The second attachment shows the valve cover removed (no bolts yet) and the valve bodies can be seen.  When they are removed as in the third attachment, you can see that the work against a brass valve plate that is set into the aluminum base.


If you look carefully, you will see that I am still able to create hockey sticks in the valve plate, and If you look closer you can see the top of a broken tap that had to be ground flush.
« Last Edit: January 08, 2019, 04:21:47 AM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #26 on: January 08, 2019, 04:41:00 AM »
These next three photos will show how the valve base and porting are put together.   Beneath the valve plate, holes are drilled through the valve base and with the valve base lifted, you can see that these holes intersect milled channels in the top surface of the main block.  These channels are connected to vertical holes that intersect with the surface of the cast iron cylinder, just behind the flange.  The final part of this is a slot that is milled into the cylinder and then a final hole drilled through the slot into the vertical hole.  If this works as planned there will be no plugged holes and all of the passages are internal.  The exhaust ports combine and connect to a straight hole through the valve base, the top plate of the main block and exit into the large open section between the cylinders.


At present, all of the aluminum plates are screwed together.  I plan to bond them permanently with JB Weld but I may wait until I can do an operational test before making the permanent commitment.




There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline sbwhart

  • Full Member
  • ****
  • Posts: 694
  • Live Long and Prosper
Re: Quarry Bank Mill Engine
« Reply #27 on: January 08, 2019, 07:04:32 AM »
Good progress Jerry interesting that you are using ally I made mine from brass but ally held together with screws/JB weld will be just as good.

To stop making hockey stick ends in slots simply drill a hole just a tad larger than the slot this will stop the cutter pulling into the corner and the size difference won't matter a jot.

Stew
A little bit of clearance never got in the way

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #28 on: January 08, 2019, 10:45:56 PM »

Stew


Thanks for the comments. I may take some different approaches to the development of this model because of my limited equipment and experience.  And also I doubt that i could actually produce parts to specification so I have to make adjustments. And sometimes I let my mistakes lead the way.

There are two big differences between brass and ally for this job. One is dollars and the other is that i have ally.  Paint will make it work.  I have some bronze on hand that i thought might work for the heads but I don't like the color much; particularly when brass will be used for piping and valves.


I have at last worked out a method of getting my photos imbedded so my next progress report may be easier to follow.


Jerry




There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Online steamer

  • Global Moderator
  • Full Member
  • *****
  • Posts: 9652
  • Central Massachusetts, USA
Re: Quarry Bank Mill Engine
« Reply #29 on: January 08, 2019, 10:54:08 PM »
Following along Jerry!   keep it coming!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #30 on: January 14, 2019, 01:36:13 AM »
More progress to report.  I have decided that bronze or cast iron are wrong for this project. The color just doesn't work out, no mater what paint color I choose so brass has been ordered and will be here this week. 



I have been dreading having to make the side thrust plates. Stew makes it sound easy but the little voice in the back of my head says otherwise.  I understand the idea of pinning or bolting the plates together and doing the milling as a single job.  The thought of milling a 3/4" wide slot in steel is what shakes me.  I have a good 3/4" drill bit for the first operation but I don't have a 3/4" slot drill or two flute end mill.  I do have a goof 1/2" 2 flute end mill but I doubt that it would live through the job.


For one thing, my mill is just barely adequate for the job in terms of rigidity.  It would leave me with a big filing job and a dulled endmill. The 1/2" wide slot might be adequate but could wind up looking aa little bit skimpy.  The slot only has to be wide enough to pass the crank arms and they will be 1/2" on my version.  I have played around with the dimensions in Alibre' and I think I would like the slots to be 5/8" wide in a 7/8" plate.   Again, no 5/8" slot mill.  A thought came to me in the night and I am anxious to try it. 


Off to the store for flat steel plate.  No problem finding 1/8" thick steel plate.  Flat is another question.  It seems that 1/8" steel in narrow widths is made by shearing or stamping from a larger plate which leave s the steel in a deformed condition.  The edges are thicker than middle and the plate is cupped on one side and curved on the other.  And the edges have been nicely rounded so customers don't hurt themselves.  But it is cheap and available.  I bought a 36" long piece labeled as 1/8" x 1 1/4" for about $4 so today was spent getting it flat and square.


My go to tool for this kind of job is a flycutter equipped with a 1/4" lathe bit with a carbide chip.  The bits are cheap. The edge lasts a long time.  And I can sharpen it with a diamond disc by eye.  Single edge tools are my friend.




flat steel 03 by captain.jerry Ginn, on Flickr


The first job was to hack of 4 pieces about 6" long.  Them stack them on edge in the mill vise and take of about 1/8 " of plate width.  I could comfortably take .010" at a time.  I did try .020" one time but the impact was  making my teeth hurt so I went with cuts of .010".  A lot of passes.


Then I flipped the bunch over and did the same thing to the other edges.  I did need to do some deburring of each piece befor putting the stack back together in the vice.  That got the edges nice and square so now I had to deal with the cupped and rounded faces.


One at a time, I put each piece in the vise, with the cupped face down and took a single pass at .005" from the rounded face.  The cut covered the full face, all the way to the edges.  Then, one at a time, I put the new flat face down in the vise and took a single .005" pass over the cupped face.  Again, this single pass cut across the full face, from edge to edge.




flat steel 02 by captain.jerry Ginn, on Flickr


All I need to do now is deburr the edges and clean up the shop.  Tomorrow I will test my idea for milling the slots.  If you don't hear from me, I will be working on a new idea.


Jerry
« Last Edit: January 14, 2019, 01:39:55 AM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #31 on: January 14, 2019, 10:15:38 PM »
Ok, I got side plates.  All bolted together, I took one more skim to be sure the edges were flat and parallel.


Side Plate l0002 by captain.jerry Ginn, on Flickr


Then I set them in the vise face up, located the centerline and spot drilled for the two ends of the slot, the con rod pivot and the connecting bars'


Side Plate l0004 by captain.jerry Ginn, on Flickr


The I drilled two 5/8" holes that form the ends of the slot.  My little HF mill could not handle the 5/8" bit so I had to progress through 3/8, 1/2 and then the 5/8".  Now comes the big idea that would make the job easy.


Side Plate l0005 by captain.jerry Ginn, on Flickr 


Side Plate l0008 by captain.jerry Ginn, on Flickr


 That doesn't show it very well, but that is a boring bit in a boring head.  The single cutting edge avoids the problem of the cutter being pushed to the side at the end of the slot and is adjustable.  The results look good so far but that is after about a dozen passes.  I could only get about .010" D.O.C. before the mill complained.   I needed another idea.  I have a bunch of 3/8" end mills that I could sacrifice for the job that have dulled edges on the end but the sides of the flutes are in good shape so I replaced the boring head with a 3/8" endmill, and cutting full depth, plowed through the center of the slot.  The cut was not difficult.  It took a little feel with the feed rate to keep the bit cutting but not to fast or tthe mill would stall and I would have to back up.  For some reason, I didnt get a foto of this operation.


In any case, I went back to the boring head for the final passes. With the center of the slot opened up, I had no problem finishing up the slot in four more passes and the a few more passes with the diameter increased a few thousandths.  I am reasonably pleased with the results.


Side Plate l0010 by captain.jerry Ginn, on Flickr




Just one note on the bit.  The stock bits are really not ground right for a hole this small.  There is not enough face angle? to get a good cut.  The bit can be rotated in the head by just a few degrees to increase the angle but then there is not enough relief behind the cutting edge so you get a lot of bumping as the heel drags in the cut.  So over to my little Unimat SL equipped with a diamond grit wheel and grind away behind the cutting edge for relief.  A little relief on the bottom edge helps too.


Tomorrow,  I will mill the tail ends of the side plates that slide in the guides and think about how to shape the outer contours.


Jerry
« Last Edit: January 15, 2019, 01:09:58 AM by Captain Jerry »
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.

Offline Captain Jerry

  • Full Member
  • ****
  • Posts: 928
  • Summerfield, FL USA
Re: Quarry Bank Mill Engine
« Reply #32 on: January 15, 2019, 11:24:09 PM »
I wasn't really complaining, more like bitching, but if you see me struggling like I was with the mill for the last few days, remember, I haven't touched a machine tool for over two years.  You can throw in a little bit of basic help or remind me of things we know but forgot, like "make sure everything is tight."  This morning I spent giving the mill a little TLC; adjusted the gibs, tightened up the backlash, aligned the DROs (cheap Igaging stuff), squared the vise.  I even repacked the spindle bearings on the Unimat SL.   The mill was a pleasure to use today.  No pics, but just saying. help is always appreciated. So are reminders.


Jerry
There are thing that you can do and some things you can't do.
Don't worry about it. try it anyway.