Hey, can anyone in the group share the known measurements of the Model T transmission early Brake Drum "Top-Hat" bearing? I see some of them given by Benson Archives parts listing pages, but would prefer to have actual measurements, even if a little worn.
Thanks,
Jim Key
Accurate Models
Need Model T transmission "Top-Hat" bearing measurments
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accuratemodelmaker
Topic author - Posts: 17
- Joined: Wed Jan 14, 2026 12:15 pm
- First Name: Jim
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RajoRacer
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Re: Need Model T transmission "Top-Hat" bearing measurments
I have a NOS one - be tomorrow before I get back out to the shop.
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speedytinc
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Re: Need Model T transmission "Top-Hat" bearing measurments
.111, .111. & .112. all used measured in an area with no wear.
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accuratemodelmaker
Topic author - Posts: 17
- Joined: Wed Jan 14, 2026 12:15 pm
- First Name: Jim
- Last Name: Key
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- Location: Woodstock, GA
Re: Need Model T transmission "Top-Hat" bearing measurments
Hmm, that's interesting, given that the call-outs for the flange have been 1 & 39/64" (1.609375"). I took and subtracted the bushing (1.50?) from the flange and got .109375" as a remainder. Reading other threads, I remembered .110", so your measurement of .111", .111", .112" seem to bear out those previous postings. This is important because looking over the Benson archive parts prints, The early Brake Drum shaft is shown to be a total of 4.686" to 4.689". The later shaft is 4.670" to 4.676" - .010" to .019" of an inch shorter. I suspect it has a lot to do with replacing the Top Hat bearing with the 3 thrust washers.
Still need depth (back of flange face to opposite edge (1.50"?)
OD of bushing (1.185"?) ID of bushing (1.002 to 1.004"?)
OD of flange (2.375"?)
Thanks in advance for all assistance. New plans for preview soon, as I've completed quite a bit, as well as 3D.
Jim Key
Accurate Models
Still need depth (back of flange face to opposite edge (1.50"?)
OD of bushing (1.185"?) ID of bushing (1.002 to 1.004"?)
OD of flange (2.375"?)
Thanks in advance for all assistance. New plans for preview soon, as I've completed quite a bit, as well as 3D.
Jim Key
Accurate Models