All "D"s are not created equal

[rustjunkie]

Type of finish, and the measurements of shells and other parts differ from the first New Departure Model D coaster brake hubs thru the "standard" 1940 and later models.
Among other things, there are differences in:
Plating on all parts
hub shell width and other measurements
Disc support sleeve measurement
Brake arm thickness

Below are some pics of an early D and a prewar 1940s D, the red paint was added and isn't orig. The point: parts are different and generally not interchangeable. Mixing of parts can cause operation and adjustment issues. I'll try to clean the images up and provide more accurate info as I have time.

 

[fordmike65]

Sticky Please

 

[rollfaster]

I like this!

 

[Freqman1]

A very worthy subject! It would be nice to know what parts go with what. This may cure a lot of hub problems! V/r Shawn

 

[Duck]

Very timely- I've got several on the bench at the moment I'm trying like hell to get 1 usable hub out of with no luck. After I saw this, I did some measuring, and found some discrepancies between the internal parts measurements my eye didn't pick up. I greatly appreciate this post- Thanks.

 

[johnboy]

This is very interesting and extremely helpful info.Now it makes sense to me why the brake arm on a hub I pieced together was slightly loose even with the lock nut tightened down.I tried another arm and it tightened down fine . I thought this was strange; because I thought that all Model D hubs were created equal in size and dimension of all parts . This info. from rustjunkie is going to be a great help to us all. Thank you !

 

[OhioJones]

Would be neat to take this one model of ND at a time and do a number of them. Seeing if actual dates of the hubs can be matched up by the part sizes included. No doubt an extremely time consuming project. I have two model D's here. One from 47 and one the original from my 41 CT. Just pulled out a 0-1 mic and already saw the differences alone just wi5h the disks. Think I will take it into work tomorrow and really get to monkeying with it while machines are running.

Scott, you're a genius.

 

[Tim Kersey]

Is the number of brake discs the same for all types & models of ND rear hubs - 21?

 

[buickmike]

I was wondering the same thing. If I have older- taller hub can disc be used from second version. I don't like seperating them. I just slide whole stack on

 

[buickmike]

Howza bout an update on this topic? I just found out I had the wider shell bilt with the shorter disc support. I thought it was tight when turning. wheel by hand. Could that have been an issue??