Model Engine Maker

Engines => Your Own Design => Topic started by: gbritnell on August 10, 2020, 04:44:01 PM

Title: 1953 Ford standard transmission
Post by: gbritnell on August 10, 2020, 04:44:01 PM
Gentlemen,
I had posted a thread in the tools area about cutting helical gears. The purpose of cutting them is for a forthcoming project, an early 50's Ford 3 speed manual transmission.
Several years ago I built a Borg-Warner T-5 manual transmission to go behind my 302 V-8 engine. At the time I knew how to cut helical gears but with the amount of gears needed for that transmission I felt it was a daunting task so the gears were all made as spur type.

Fast forward to this project. I completed the Galion road grader and was a little burned out so I didn't want to get back into metal cutting right away. I finished up a couple of projects around the house and completed a couple of plastic model airplanes that I had started quite awhile ago.
When I got the idea for this project a friend of my son has several old flathead powered cars with manual transmissions. He also has quite a few parts laying about and graciously loaned me a trans to take pictures and dimensions. I measured everything and took photos. From there I drew the trans (full size) in Autocad. The next step was to scale it down (1/3) to fit my flathead V-8 engine. The usual modifications were needed when scaling something smaller, metal wall thicknesses, bearings that would fit the scale, and in this case calculating and machining the required gears but this time they would all be helicals and not spurs.

Between the work that the late Chuck Fellows had done creating the fixture and the wonderful spreadsheets that Don1966 created I converted all the gears over form spur to helical while maintaining the proper center to center shaft spacing. The nice thing about making helicals is that by a simple change of helix angle you can change the P.D. of a gear.

With spur gears you just figure out what D.P. you are going to use and how many teeth are on each gear and this will give you the P.D. Quite straightforward. To make helical gears first you need the cutter. It is possible to use standard involute cutters but then you need quite a few of the set of 8 to cut the proper tooth form for a given diametral pitch. In my case I made my own cutter which started from a piece of .50 diameter W-1 drill rod. I use W-1 rather than O-1 because it cuts a little easier. With the small diameter cutter I didn't have to worry about the tooth form changing so I split the difference in the range of gears I was cutting and went with the recommended cutter for the needed tooth count. The cutter shape was formed using a hand ground H.S. lathe tool. It was then gashed with the dividing head (4 teeth) and each tooth was relieved using a small burr in a hand grinder. I left about .040 of the tooth shape in case I needed to sharpen the faces. The cutter was then hardened and the faces polished with a diamond lapping stick. I didn't anneal the cutter as it had enough tooth thickness that I wasn't worried about breaking any teeth.




Title: Re: 1953 Ford standard transmission
Post by: crueby on August 10, 2020, 04:54:26 PM
This sounds like a great project, am sending the shop elves out for more popcorn....


 :popcorn: :popcorn: :popcorn:
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 10, 2020, 05:01:30 PM
The next step in the process was to make the helical templates. There are 8 gears in this transmission so 8 templates would be required. When Chuck built his fixture he used 1/8" thick aluminum. I tried this once and didn't have much luck so I make my templates from 1/32" brass sheet. Each template starts out with the long dimension as the circumference of the 1.00 diameter mandrel (Pi or 3.142") The other dimension is 1.60". All the plates were cut to size and squared up then each plate had 2 small slots cut in the ends. These would be for mounting the template to the arbor. Using Don's spreadsheet the offset dimension was calculated and each template was set up in the mill and the required angle was cut. To get them exact I used my dial indicator and and digital readout to measure the angle. (Tangent of each angle times  the -X- travel. The angular piece was cut off with a small slitting saw. With all the templates cut they needed to be formed around a piece of 1.00 diameter rod so they were all annealed prior to forming. I clamped each template against the bar in the mill and started forming the radius. I could only get so far around so by holding the already started radius against the rod I pressed it all around to get it rolled into a complete circle. There is always a little spring in the material so I roll the stock a little tighter then slip it back over the bar and tap it lightly with a piece of soft wood. This forms the template into an almost perfect radius. Each template was then marked with the proper information so I wouldn't get them confused in use. When the templates have a very steep angle material needs to be removed from the opposite side so that the roller follower will get down far enough to use the full travel of the mandrel.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 10, 2020, 05:13:14 PM
The next part of the gear cutting process was to make the index plates. I already had 3 from previous jobs and a couple of them had the right hole spacing to use for the new gears so I only had to make 2 more plates. The plates are 12L14 steel. The O.D. is 1.94 with an .84 x .25 diameter boss. The through hole is .375 reamed to fit on the arbor. It also has an 8-32 tapped hole for a set screw to lock it to the shaft. The plates were turned then the stock was put in the mill vise and centered. Using the hole function of the digital readout the required number of .125 diameter holes were drilled and reamed. The plates were then cut from the stock and the flange was turned to the proper thickness.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 10, 2020, 05:26:35 PM
Here are a couple of pictures of the fixture. I added a tapped hole in the top of the fixture for a locking screw. I made a brass shoe so the locking screw wouldn't mar the shaft. The shaft is .50 diameter drill rod that is polished to fit into the reamed hole. There's quite a bit of hammering when cutting so everything needs to be as tight as possible. When cutting I very lightly tighten the locking screw just to add a little resistance to the shaft. The other thing when cutting is always and I really mean 'always' conventional cut. If you tried to climb cut the cutter would grab the stock and ruin the part and the cutter.
On the top of the fixture is a bar with a ball bearing on the end that rides against the template. It works very nicely when cutting. You just need to keep tension against the template. At the rear of the fixture is the mandrel that holds the template. This is free to rotate on the .375 shaft. The index plate is locked to the shaft and in my case I use a knurled brass pin as my index key.
Title: Re: 1953 Ford standard transmission
Post by: cnr6400 on August 10, 2020, 05:31:31 PM
I have also ordered a dump truck load of popcorn  :ThumbsUp:

I worked on a few of those old boxes at my Dad / Grandfather's garage when I was a kid, it will be interesting to see one built in miniature. Most of the work we did on them was shifter and bearings related, as they came off 30-40 yr old farm trucks and equipment, many had done about a million miles, and everything except the gears was just plain worn out. When they wouldn't shift any more, or the oil was running out either end, we would rebuild them and off they would go again. Parts were dirt cheap for them in the late 1970's early 1980's.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 10, 2020, 05:48:31 PM
At the end of the fixture arbor is an adapter that holds a mandrel to mount your gear blanks on. I have several different sizes depending on what size gears I'm going cut.
The gear blanks were turned, drilled and reamed and cut off. They were then cut to thickness (.25 dia.) They were mounted to the mandrel and held in place with an 8-32 Allen head cap screw.
Six of the gears have a helix angle of 28 degrees. The other two are 31 degrees. I used my angle blocks and taped them together to get the required angle. The fixture was set against the angle blocks and the vise snugged up. Just to make sure I checked the angle with my indicator to verify it. All was good.
So here you have the 8 gears that will make up the transmission and a group shot of everything that's required to make them. Once you have made a few it's actually very enjoyable especially when they come out good. That's not to say that I haven't had my share of oops along the way. With this project I only had 3 oops. One was the aforementioned climb cut. Although I hadn't intended on making a climb cut I had the blank a little too close to the cutter when I indexed it, it grabbed and luckily no harm was done, except to the blank. Another oops was when I was indexing the fixture. Each of the index plates has 2 rows of holes. One plate has two rows that have almost the same number of holes. It wasn't until I finished cutting the gear and took it off the mandrel that I realized one of the teeth wasn't the same shape as the others. What happened was the fixture is at an angle so it's a little hard to see the holes and as I was indexing at one point I put the index pin in the wrong row of holes. The two rows happened to have 2 holes that were pretty close at that point and I chose the wrong one. (One thin tooth and one thick tooth) The last oops was a template error. When I cut the helical angle onto the template I cut it from the wrong edge so instead of 47 degrees I had 43 degrees. (Bad gear new template).
The two small gears are the reverse idler set. One goes on the countershaft to drive the reverse idler but has to clear the slider as it engages the idler.
Title: Re: 1953 Ford standard transmission
Post by: Johnmcc69 on August 10, 2020, 07:31:46 PM
 :ThumbsUp:
 Another great project George!
 I'm looking forward to following along & learning.
 :popcorn:
 John
Title: Re: 1953 Ford standard transmission
Post by: Roger B on August 10, 2020, 07:55:35 PM
That's some rather clever stuff  :praise2:  :praise2: I will be following along  :wine1:
Title: Re: 1953 Ford standard transmission
Post by: Admiral_dk on August 10, 2020, 09:43:24 PM
Great start to another project I will follow  :cheers:

Looking forward to see how many differences there are to most modern motorcycle boxes I've seen - I only ever seen the inside of a VW Beetle box (once) when it comes to cars.
Title: Re: 1953 Ford standard transmission
Post by: derekwarner on August 10, 2020, 11:26:56 PM
I too have experiences with a 1950's Ford geabox.......

It was in a Prefect Utility, hand painted dark Green and kept on jumping out of second gear ...yes, the vehicle I finally learn't to drive in.....[after much yelling  :Director: from my Father]

Watching on with interest

Derek
Title: Re: 1953 Ford standard transmission
Post by: Art K on August 10, 2020, 11:42:42 PM
George,
This looks to be a very interesting project. I'll be following along. My only transmission rebuilds were Volvo 140 series 4 speed, easy. And a Saab 99, PITA.
Art
Title: Re: 1953 Ford standard transmission
Post by: Don1966 on August 11, 2020, 02:29:21 AM
Looking forward to more updates George and the gears look awesome. From what I read you used one cutter for all the gears that saves much time. The other thing you mentioned was dial indicating the setup template to check the angle. I am sure some would enjoy a lesson on how you go about doing that if it’s not to much to ask. Maybe on another thread You could show it if it’s to much from here.
Also enjoyed our conversation the other day it was great to hear from you. I been working on a spiral gear and helical spreadsheet fir future use not sure how it will end yet. Spiral gears are different as to the relationship to the shaft but has helical angles, so this complicates things for me but we will see. I just need to research them more.


Regards Don
Title: Re: 1953 Ford standard transmission
Post by: nj111 on August 11, 2020, 09:48:38 AM
Watching with great interest and keen to learn more from you George!
Title: Re: 1953 Ford standard transmission
Post by: sid pileski on August 11, 2020, 04:42:12 PM
George-
I'm watching too. Very nice work as usual.

Not to derail this thread, but in you first post, you mentioned "the late late Chuck Fellows".
I'm not on every day, so that is news to me that I'm saddened by.
When was that? Was there a thread or link to an obit?

Again, apologize for the kink in your thread.

Please disregard.. After I posted this, I did a search (should have done that first!). I found the notice.
Still sad.


Sid   
Title: Re: 1953 Ford standard transmission
Post by: Craig DeShong on August 11, 2020, 08:48:05 PM
Hi George

I’ve built my version of Chuck Fellows’s helical gear cutting fixture and have used it on several projects now.  Making custom gear cutters is way beyond my skill set yet.  I’ve just been purchasing involuted cutters when needed, but the cost, as you know, can get high.  Granger tools in the best supplier (here un the US I’ve found) for purchasing involuted cutters.

I sure wish I lived near and could stop by and get a crash course on how you make the involute cutters; it’s a skill I’d like to add to my ‘tool box’.

This is going to be a fastenating project; I’ll surely be following along.

Title: Re: 1953 Ford standard transmission
Post by: Don1966 on August 12, 2020, 02:12:04 AM
Craig I made a spreadsheet to help make cutters and Hobbs to cut gears with and all the diffent gear calculations. If you want it PM me with your email address and I will gladly send it to you. I tried to post it in plans and drawing but it’s to large a file. If you haven’t got the book ( gears and gear cutting by Ivan law get it. Amazon has it for about $10. It’s money well spent.

Regards Don
Title: Re: 1953 Ford standard transmission
Post by: Zephyrin on August 12, 2020, 09:14:18 AM
I'm always impressed by the care with which you describe your machining methods, it's hard to find more useful than these posts...

I too was blown away by the ingenuity of the Chuck Fellows device for cutting helical gears, and of course I too embarked on making my own version of this device, which allowed me to make the helical gears of a mini 4T engine, my last one. I'm very proud of these gears even if they are hidden inside!

I have acquired new expertise thanks to these gentlemen, for which I am very grateful.


Title: Re: 1953 Ford standard transmission
Post by: mikemill on August 12, 2020, 09:46:31 AM
For those interested in gear cutting this book is by a well respected engineer.
https://www.teepublishing.co.uk/books/gears/gears-and-gear-cutting/
I have used it for many years good referance.

Mike
Title: Re: 1953 Ford standard transmission
Post by: Jo on August 12, 2020, 10:21:57 AM
Yes that is the book Don was referring to   :)

Jo
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 25, 2020, 01:51:21 PM
 I started on the gear case. It began with a block of aluminum. I squared it up to the required dimensions then added all the tapped holes, front, side and rear. The full sized box is a casting so therefore is enclosed on all sides, other than the access window and holes. To make this one I designed it so I could do all the internal machining from the front end and then make a cover plate that would match the contours. The case was rough drilled then bored to the proper size. The gear box has a tapered relief hole offset from the main centerline (countershaft gear clearance). It would need to be stepped into the block so there was 2 ways I could do it. One was to mount it on my rotary table and using a ball mill step the shape into the box. The other which I deemed a lot less work was to just use the boring bar and make steps similar to using the rotary table but wouldn't necessitate tearing down the vise and setting up the rotary table. I calculated the steps and started removing metal. When you're doing a job have you ever had the feeling that it sounds like your cutting more than you should be. Well that was the case with this operation. The first cuts were made with my larger boring bar but I needed to switch to a smaller one to finish the smaller tapered radius deep in the box. I made my setups the same but only subtracted the radius instead of the diameter dimension when adjusting the boring head. (head reads in diameter) I made a couple of cuts and it sounded like too much material was being cut and sure enough it was. After realizing my mistake I reset the boring head and finished the cuts. I ended up with a small circular notch in the taper which won't affect anything as the metal wall is thick enough to accommodate it but  it was one of those crap moments. I already had 4 hours in the part so I filled it with JB weld for no other reason than to make the tapered hole smooth.
 Next up is the front cover plate. I started with a piece of aluminum that was about 3/8" larger per side than the finished piece. This would allow me to clamp it for the needed machining. I started in the vise and put the holes in then transferred it to the rotary table. The back side has a raised boss that has the same shape as the window opening in the front of the gear box. I cut the radii and sides right to the calculated size then stepped the cutter down leaving about .008 from breaking through. I cut the perimeter shape then removed the piece and sawed the framing from the part. Even though the radii and sides were cut to the calculated dimensions (radius of part plus radius of end mill) they came out a bit large so some filing was necessary to get a good fit. As seen in the picture the front face has some countersunk holes. These will be to secure the cover to the gear box. When it's finished I will remove the temporary screws and make up aluminum countersunk screws. I thread the screws and turn the head diameter a little larger than the diameter of the countersink. Leaving the screw on the bar stock I then tighten it in the hole and cut it off leaving a small protrusion. This gets milled and filed flush so it will end up that the screws will be almost invisible and make like the gear box is a complete enclosure.
 The last piece for the day is the countershaft. All of the gear were made .250 wide but needed to be adjusted to the required dimensions so I made split bushing to hold them in the lathe and faced them to size. While running true in the split bushing I also opened up the center hole to the needed size. Two piece were needed to join the gears and make it look like one shaft. The pieces were turned with a shouldered diameter on both ends. I then used a tool with a radiused end to form the fillets up to the shoulders. The pieces were a light press fit into the gear and also had a coating of high strength Loctite applied.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on August 25, 2020, 01:55:35 PM
If someone notices that the small gear on the end of the shaft has the teeth going the other way that because that's the reverse gear. It drives the idler gear which needs to mesh with the first/reverse slider gear on the mainshaft. So it's left, right, left. The outside diameter of this gear is just slightly smaller than the root diameter of the gear ahead of it. The first/reverse slider gear meshes with the second gear from the right (low gear) then it slides on splines to the rear where it will mesh with the reverse idler gear.
Title: Re: 1953 Ford standard transmission
Post by: bernienufc on August 25, 2020, 02:10:38 PM
Threads like this one are a goldmine, long live the forums. I know George has answered some of my questions via email in the past but how can you not love reading these threads again and again, i just wish i could have spent my youth in better ways when i see what is capable with the skills shown here.
Following with avid interest :-)
Bernie
Title: Re: 1953 Ford standard transmission
Post by: nj111 on August 25, 2020, 08:32:11 PM
Great progress, especially love that little cluster of helical gears.  You made a minor machining error so you are human after all!  Myself, I  have to make 2 or 3 of everything to get one item correct!
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on September 02, 2020, 03:17:43 PM
I have all the gears, splines, shafts and collars finished and installed in the gear box. I had to make two cutters up to cut the splines on the input shaft and the output shaft. The spline (male) were cut from a length of spline shaft I had purchased when I was building the Borg-Warner T-5 transmission. I purchased a piece of spline bushing to match and cut 2 pieces from it, one that was pressed into the low gear gear and the other for the 2-3 shift collar. It took a little modifying and hand work to get the reverse idler gear meshing properly with it's mate on the countershaft.
First picture the input spline shaft.
Second picture looking into the gear box toward the front end with the countershaft and the input gear with spline.
Remaining pictures are a box full of gears and a couple of overall shots.
Title: Re: 1953 Ford standard transmission
Post by: Don1966 on September 02, 2020, 03:47:46 PM
That is awesome George love the gears and all the work that goes into them.... :Love:




 :cheers:
Don
Title: Re: 1953 Ford standard transmission
Post by: Roger B on September 02, 2020, 08:04:56 PM
Excellent  :praise2:  :praise2: Can you put a ruler or similar in a shot to give me an idea of the size of the gearbox?
Title: Re: 1953 Ford standard transmission
Post by: Craig DeShong on September 02, 2020, 08:52:38 PM
Excellent  :praise2:  :praise2: Can you put a ruler or similar in a shot to give me an idea of the size of the gearbox?

I was about to ask too Roger, but you beat me too it.  Fantastic work as usual George. :cheers:

Title: Re: 1953 Ford standard transmission
Post by: Admiral_dk on September 02, 2020, 09:22:51 PM
Fantastic work George  :praise2:

As I never saw one of these before, I have to ask if I got the function right ....
I know that the shift forks are not installed yet - am I right in guessing that the pictures show the box in neutral ?
If we move the left fork all the way left it's in top and the power goes straight through (1:1) ?
Move the left fork as far right as it should go and we are in second gear ?
Move the left fork back to it's middle position, and if we instead moved the right fork as far left as it should go, the box is in Low or first ?
Finally move the right fork all the way right and it's in reverse ?

Or have I got it completely wrong ?

Best wishes

Per
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on September 02, 2020, 09:41:49 PM
Hi Per,
You are 100% correct.
Title: Re: 1953 Ford standard transmission
Post by: Admiral_dk on September 03, 2020, 11:43:53 AM
Thank you George - nice to know that my deduktive skills hasn't gone completely down the drain (I had to look for a while though).

Looking forward to see how you will do the shifting mechanism  :cheers:
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on September 09, 2020, 01:24:46 PM
The next couple of pieces are the shift plate and the 2 shift quadrants. The shift plate is made from one piece of aluminum. It involved multiple setups which included setting up and removing the rotary table twice. The block was cut to size and the mounting holes and quadrant holes put in. The outer shapes were done first. I roughed the two bosses cutting to depth. Some of the mounting holes are on pads because of the angles surfaces so the plate was set up in the mill vise at the proper angle then the surface was cut, staying away from the pads. A fixture plate was drilled and tapped to hold the shifter plate so that it could be set up on the rotary table. Two bolts were made with a close fitting shaft and a 6-32 thread.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on September 09, 2020, 01:31:19 PM
The piece was turned over and the back side was cut. Stock was left for the 2 round bosses and the center square boss. The angled surfaces that match the outside shape were stepped off with a ball mill because there wasn't enough thickness to clamp the piece in the mill vise. The rotary table was then set up again, indicated and the fixture plate and part were mounted. The first boss was cut then the second. The square center boss is for a spring with .094 balls at each end the ride in the detents in the shift quadrants. The machining was completed then the part was filed and polished.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on September 09, 2020, 01:41:33 PM
The shift quadrants are fabricated from 3 pieces and silver soldered together. The plate was cut as a rectangle then the holes were put in, one for the center shaft, one for the shift fork and three for the detents. The shaft was made from .156 diameter drill rod. One end was turned down to .125 to fit in the plate the other end was threaded 3-48 to hold the shift levers. The boss where the shift fork goes was turned with a tiny collar to act as a stop when slid in place. The parts were assembled then soldered. After cleaning up I mounted them in the dividing head. I put .093 drills into the detent holes and indicated across them to get the part flat. There was no other way to get the part in the correct orientation for the milling operations. Using my CAD drawing I machined the curves and steps into the plate. Both were done this way then the additional radii and shapes were hand finished.
Title: Re: 1953 Ford standard transmission
Post by: Admiral_dk on September 09, 2020, 09:33:38 PM
Some very complex shapes and many way this could go wrong .... but I guess that you need the challenge to keep it interesting for yourself George  :praise2:

The square boss must be for the spring loaded 'locating/locking pins' that keeps the transmission in the selected gear  :thinking:
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on October 05, 2020, 10:19:43 PM
 It's time for an update on the transmission. Work is progressing well but it's time to machine the outside of the main case. This will involve a tremendous amount of stepping and blending of cuts. I made an adapter that bolts to the front plate of the transmission. This will allow me to cut the outside radius for the housing which goes over the mainshaft. The other half of the cavity has the same radius but is offset by .625 but there is only a small amount that needs to be removed so that could be stepped of rather than making another whole adapter to bolt to the front of the trans. I did need to make a second adapter which will allow me to cut the radius over the countershaft. This is a bulbous enlargement which needs to blend into the already cut shape over the mainshaft.

I started by bolting the front cover plate to the trans. To this I mounted the adapter shaft. The round adapter was first put in the dividing head and indicated true. It was then removed and put in a second and third time to see how accurate the concentricity stayed. The reason for doing this is because once the trans case was mounted to it I couldn't get an indicator into the tight space to check it. In doing this the part stayed concentric within .002.

I roughed the shape with a .375 ball mill then changed to a .187 ball mill. I had to stay away from the end flanges because the ball mill will dig in a little and if the cut is made right to the flange it will leave a divot. Once the cuts were made then the flange surface was finished. On the top surface there is a long boss which needed to be stepped over.
 
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on October 05, 2020, 10:44:49 PM
 In working the other side of the radius it blends into a flat surface which tapers off to the far side. I kind of guesstimated a stopping point so that I wouldn't go to far into the bulbous projection.
With this radius work done or done to a point I took the trans case from the dividing head and removed the adapter mandrel and front face cover. The new front face cover was mounted and the mandrel bolted to it. Before bolting it up I indicated the mandrel like I had done in the beginning just to make sure it stayed concentric. I did.

 The trans case was then remounted in the dividing head and the second radius was stepped off. This shape is not only round but conical in form and has to blend with the first radius. Whew! While stepping it off I had to work around the two bosses, one on the bottom, a drain boss, and one on the side, a fill boss. When doing the machining on the case the holes for the drain and fill were put in so I marked the surface with a sharpie and put a plug in the same diameter as the boss. I scribed a line around it to give me a guide to cut to.

 Here is the procedure for cutting this shape. I had previously made up a step chart that followed the cone shape. With the part mounted in the dividing head it would rotate around this shape. I touched off the cutter and went to depth. I would rotate the dividing head until the cut got close to the first shape. Leaving my Z depth I would move the cutter over the first radius and rotate the dividing head until the cutter would just start to grab a piece of paper. (.003-.004) I now had the point where the Z radius would blend into the first shape so I would then move the table back in X until I got to the proper dimension for that step. It sounds quite complicated but in truth it's not. The biggest thing is staying focused on all the cuts.
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on October 05, 2020, 10:48:18 PM
 With all the cuts really close, well close enough that I didn't have a large amount of metal to file off, I went back to the bosses and stepped around them. At each point around the radius I would have to go out onto the shape to set my Z depth then back in until I was close to the line.
Title: Re: 1953 Ford standard transmission
Post by: deltatango on October 05, 2020, 10:52:12 PM
That is a masterclass in staying focused!

I'm looking forward to seeing the final result.

Regards, David
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on October 05, 2020, 10:56:08 PM
 Now comes the fun part, burring, filing and sanding. The whole part was painted with an ink marker then the filing started. The idea is to remove just enough metal until the marker line disappears. For corners round riffler files of various shapes were used to blend the shapes together leaving a radius in the corner. I'm guessing I have about 5 hours of filing and polishing to get all the marks blended out.
With all the hand finishing complete I tapped the holes for the drain and fill plugs. (5/16-24)
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on October 05, 2020, 11:08:07 PM
 The tailshaft housing needed to have a motor mount on it. There was no way to machine it in one piece so the tailshaft was machined and finished. I then machined the motor mount bracket and finished it. To mount it to the tailshaft I set the tailshaft up in the vise and indicated it true and centered. I then cut a .150 x .565 slot with a .125 end mill and drilled and tapped 2- 2-56 threaded holes. When making the bracket I cut the radius that matched the tailshaft by stepping it off. I had to leave a small projection which would locate into the slot in the tailshaft. This required filing, fitting, filing and more fitting. I had the part on and off so many times that the small threaded holes gave out. The necessitated making a steel piece that would go inside the tailshaft housing with the two matching threaded holes. I finally got it to fit reasonably well. This was after about 4 hours of work. And people wonder why it takes so much time to build an engine or model.

 The last two pictures show the tailshaft mounted to the trans case.
Title: Re: 1953 Ford standard transmission
Post by: MJM460 on October 06, 2020, 12:59:49 AM
Wow, George!  That takes the “step and incremental rotate” technique to a whole new level.  Who needs CNC?  And some complex geometry in that spreadsheet behind that simple looking column of handwheel settings.  I bet you didn’t need any interruptions to that sequence.

Another masterclass in your continuing series.

Thank you for taking the time to post that process in such great detail.

MJM460
Title: Re: 1953 Ford standard transmission
Post by: crueby on October 06, 2020, 01:43:45 AM
Took a while to get my jaw off the floor so I could type. Just stunning.   :praise2:
Title: Re: 1953 Ford standard transmission
Post by: deltatango on October 06, 2020, 02:07:43 AM
OK, now I can see the final result! Wonderful work!
David
Title: Re: 1953 Ford standard transmission
Post by: gbritnell on November 05, 2020, 04:33:18 PM
Well a transmission is no good if there's no way to shift it so I borrowed an old shifter from a friend and made a drawing. After building and adjusting everything I realized that  the shift levers on the transmission were too long which allowed the shifter pin in the shifter to over travel and pop out of position so new levers had to be made that were about .200 shorter. The rods are 4-40 thread (.112 dia) which isn't a standard SAE size so I had to turn them from .125 diameter stock. The longer one is 3.25 long so it needed a center as it got farther out from the collet. The shifter ball is .625 diameter. Using a radiused end high speed tool bit I stepped the front part of the radius off then filed and sanded the shape smooth. I stepped off the back side getting close to cut-off then parted it off. The ball was then mounted on a 4-40 mandrel and the radius finished. The ball was then buffed and polished.
In the old hot rodding days this is what would have been used to convert a column shift car to a floor shift. In the day there were quite a few companies making these the most notable was Hurst.
Title: Re: 1953 Ford standard transmission
Post by: Admiral_dk on November 05, 2020, 04:50:04 PM
Another fantastic addition to your complete Engine + Transmission system George  :praise2:

I guess that it shifts as a 'H' pattern though I can't see the details of that.

Best wishes

Per
Title: Re: 1953 Ford standard transmission
Post by: tghs on November 05, 2020, 05:01:26 PM
very very nice.. tops it off well..never want to be caught shiftless
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