3D Model T transmission project - help needed

[accuratemodelmaker]

Hello everyone,

After being away for several years, I have decided to renew my membership and return to this forum with what will hopefully be received as a interesting project, worthy of members help.

Years ago I started a plan drawing of the Model T transmission, mostly because I wanted to know how such a simplistic mechanical device actually worked. Over time I grew increasingly interested and started a 3D representation. However, not having all the parts has been difficult to say the least, in obtaining accurate measurements. I had some of the parts from 2015 and recorded what I could then. Much of the remainder has been educated guesswork, and some obtainable info. The ultimate goal with this project is to complete the transmission plan that I started years ago and offer it up anyone who might want such a collectible.

I'd like to request, anyone who has some free time to lend, help with parts measurements. Either contact me here or via my e-mail address customreplicas@att.net. I would state that this is based on the earlier version (around 1915). Hopefully these previews will give some idea of what I'm trying to accomplish.

Many thanks in advance,

Jim Key
Accurate Models
5130 Farm Place Dr.
Woodstock, GA 30188

[varmint]

I would think that obtaining a transmission for the project may be worthwhile. You can always sell it afterward.
Vernon

[speedytinc]

15 transmissions didn't have starter ring gears.
The only part I can identify as actually 15 is the 3 piece triple gears.
You got a long way to go. Pre 16 transmissions are very different to the mostly post 1920 parts I see here.

[accuratemodelmaker]

I based the 1915 on there being two bushings inside the brake drum shaft. Read they changed in 1916. Really no other reason.

When did the starter and ring gear begin? I'm not opposed to dating this correctly, or altering the plan to make this correct.

As to acquiring a Model T transmission to measure off of, the idea has crossed my mind, but simply cannot afford that right now.

Thanks for the opening critique.

Jim Key

[Dan Hatch]

Jim I see your in Woodstock Ga. Email me by forum. I am in zip 35173. I think I can hook you up. Dan

[speedytinc]

I based the 1915 on there being two bushings inside the brake drum shaft. Read they changed in 1916. Really no other reason.

Lack of upper bushing(2nd) was done late, 26-7?. 15 had a big brass hat bushing that was part thrust bushing.
The casting is very different dimensionally & visually. Different clutch disk count & a thick spacer.

When did the starter and ring gear begin? I'm not opposed to dating this correctly, or altering the plan to make this correct.

19, but the hat bushing remains.
I would date what you have as 21-25. Not 100% sure off the top of my head when the riveted triple gears were discontinued.

As to acquiring a Model T transmission to measure off of, the idea has crossed my mind, but simply cannot afford that right now.

A CORRECT early transmission is not going to be that easy to acquire.
I am looking for an early brake drum to finish my study. Good ones get reused, bad ones get pitched & replaced with later ones.

Thanks for the opening critique.

I have been recently studying the differences.
There is much disinformation & incorrect information mixed with a few correct facts in past forum posts.
You have to know to recognize what was correctly posted.

Jim Key

[accuratemodelmaker]

The earlier brake drum drum is what I am after. I was told they replaced the thrust bearing with 3 washers (.026", .042", .042") to create an .015" to .027" clearance.

If 192something is what I am making, then so be it.

I based the brake drum off ebay shots labeled 1912-1920 or so. I am not making the 25-26 wider brake drum and drive plate.

Will be interesting to see what the members here come up with. I did look at Martin Vowell's drawings as well.

Thanks again,

Jim Key

[speedytinc]

"The earlier brake drum drum is what I am after. I was told they replaced the thrust bearing with 3 washers (.026", .042", .042") to create an .015" to .027" clearance."

No.
Part of the misinformation Ive been wading thru.
The hat bushing was replaced by 3 - .042 washers from early 20 on. Clutch hub changed also.(service bulletins)
If you don't have a usable hat bushing for your early rebuild, you can use 2 of the .042 washers & a special .026 washer. That combination replaces the obsolete hat bushing. This is a vendor provided fix. Not OEM as best I can tell.
OR.... you use the 3 thick washers & a later clutch hub. Or you can remove .015" from the early clutch hub thrust surface with the 3 .042" washers.

Gets messy don't it?

[accuratemodelmaker]

Yes, it does. But, I am taking notes and will endeavor to make a plan that reflects what ideal O.E.M.

I suppose then, that shooting for 1920 is perhaps the best shot, or is it 1925?

Is this the correct Clutch disk drum?

Thanks again.

Jim Key

[speedytinc]

1920 after April? (my reference material is @ home)-1925 same until the wide drum

"Is this the correct Clutch disk drum?"

This is the most confused part. How to identify.
Since I see ford script on top, I would say, yes, its correct for 20-22?.(late using the 3 thick thrust washers.)
Some time later the back side has a beefer looking casting. Probably 22-27.

As another point, on the 3 washers. The thin one I had & are available look the same OD wise as the thick washers.

[accuratemodelmaker]

Okay, getting somewhere. Will add to my notes. Our discussion today has been very enlightening.

Here is the back of my brake drum (thus far). I tried to match the photos of the drum we had.

Having trouble IDing the Drive plate bolts. Says they are 3/8" x 13/16" - 16 TPI - coarse.

Thanks again,

Jim Key

[speedytinc]

3/8-24. Fine thread. I cant confirm length where I am now.

[John E. Guitar]

Nice work.

I drew up the Model T transmission for a university project back in the nineties using Solidworks 98.

I saved it all to floppy disks which unfortunately have long since disappeared.

[accuratemodelmaker]

Thank you. This is a project full of ever changing details, as today pointed out.

I admire anyone who has attempted to recreate this transmission.

Jim Key

[dykker5502]

Can't you get original blueprints from the Benson Ford arhives?

[J and M Machine]

Can't you get original blueprints from the Benson Ford arhives?

Yes: as we had to. Making the drums and gears to their exact dimensions and specifications.
You have to pay for them and we had to sign an agreement.

[accuratemodelmaker]

I have the general plans from the Henry Ford archives, but did not know there were more detailed plans available from Ford. May I contact you privately to ask who you spoke with at Ford for such info? Not sure I can afford the usage fees right now, but worth checking into. In the meantime, I will just measure actual parts as they become available.

Jim Key
Accurate Models

[DHort]

Have you looked at all of Martin's drawings yet?

I know they are on here somewhere. I just cannot find them right now.

[Mike Silbert]

Here is the information on the Vowell Drawings
https://mtfca.com/phpBB3/app.php/gallery/album/5

He also has lots of stuff on his Facebook page, if you belong to Facebook.

I was @ the Cabin Fever Expo (https://www.cabinfeverexpo.com/) over the weekend and there was a 3D printed Model T transmission, a simplified version 2" long
Plus a Model T engine/tranny locked in high gear with moving engine parts.
And a fully moving flathead V8 about 6" long.
I think about doing 3D printed models sometimes but I end up working on the full size functional parts.
There is a box full of 3D printed casting patterns next to my desk for various parts.
And a garage full of real parts and cars needing my attention also
Mike

[speedytinc]

Have you looked at all of Martin's drawings yet?

I know they are on here somewhere. I just cannot find them right now.

Vowell art incorrectly pictures & denotes the wrong clutch packs listed as 14-16 & 14-17 drawings.
So watch out what you use for references. Those errors will cost potential clutch failure & another motor pull & tear down.

[accuratemodelmaker]

Part of what I intended from the start was the possibility of making a "Visible Model T transmission", so that the operation could be understood. Short of that, I may explore Solid works animation of the 3D parts I'm making so that one can observe the action of the low and reverse bands being applied. I haven't see a clear animation showing this yet, just descriptions. 3D models are great proof of concept so long as they are mechanically accurate, and not subject to stresses that only metal can handle.

At the very least, be able to offer a print schematic of the 1922-25 range transmission version, which I'm getting a fast education on. I have looked at Martin's work, which I find to be a nice presentation, but don't have the expertise to know if these are correct depictions of the time periods. I will be looking to have several authorities on Model T parts look over my works, before posting, or offering them to this group.

Case in point, just finished the clutch pack last night, only to find out that the large disk were originally circular with 2 flat sides. Will have to correct those going forward.

Jim Key
Accurate Models

[Mike Silbert]

The 6 flat sided disks are the "26-27" style and also sold as replacement parts later in production.
They are also required when using the replaceable lug up to '25 drums.
The brand new drums being made require these.
You drew a valid Ford part, just not the target year.

99% of the Model T parts changed between car #1 and car #15 million.
Plus owners and mechanics have been mixing them up for 100+ years now.
The finer details of the Model T is a tough study

Finding someone with experience and parts near to you might help limit the confusion.
The Southern Peach T's chapter is near you
https://www.mtfca.com/chapters/#ga

Mike