Help wanted with Pinioin Depth Gauge

[Ian Vincent]

I have recently acquired a 1930's to 1940's Pinion Depth Gauge for Buicks. See the attached photos.

 

It was all rusted up when I got it but I have been able to free off the micrometer and it is still accurate - its only a very fine thread after all so there isn't much that can go wrong with it.

 

The two discs are designed to fit in the bearing caps for the crown wheel making it easy to set the depth of the pinion from the CW axis. As is to be expected the discs are too large for a TR3a/TR4 axle. Hence my need for some assistance. I don't have a lathe.

 

I also can't be positive about the diameter of the CW bearing races on a TR axle, I think it is 72.24mm (from some notes I made when I reset my current CW&P) but I can't be positive so two questions?

 

1. Does anyone know the diameter of the bearing races for a TR back axle, can you confirm my figure of 72.24mm
2. Is there anyone out there with a lathe who would be prepared to turn the discs down to the right size - once I have confirmed what that is? I'm happy to pay for it.

I know I could take the discs to a local machine chop but I thought I'd ask on here first as I suspect I can be guaranteed an accurate result from someone on the forum.

 

Rgds Ian

 

PS The gauge will be available for anyone to borrow once i have got it working and checked it by using it on my back axle - I am intending to change the ratio this winter.

 

PPS why can't I edit my typo in the title?

Edited November 19, 2017 by Ian Vincent

[Lebro]

Provided the discs are not hardened steel (check with a file) I could do this for you.

I live in leatherhead Surrey, so you would have to post it I guess.

 

Bob.

[Colin Fairhurst]

Hi Ian,

I have got two old crown wheel carrier bearings here out of a TR3 " Girling axle". They are "Timken 16283". Perhaps you can search the dimensions from that. Using my digital vernier gauge (of unknown quality/accuracy) I can only get as close as 72.27mm to your dimension.

When I get hold of my larger micrometer I will try to measure them again.

If it would help I could send one of these old bearings to you.

 

Rwegards, Colin

[RogerH]

here are the Timken dims

 

https://www.bearing-king.co.uk/bearing/16150-16283-timken/11991

 

 

Roger

[Ian Vincent]

Many thanks Roger, so my 72.24mm was correct.

 

Colin if you could send me one of your old bearing races I would happily reimburse the postage.

 

Ill pm you the address later.

 

Rgds Ian

[john.r.davies]

If this special tool was made so that zero depended on the size of those discs, then you might have to adapt the technique with modified discs, to include another reference point.

 

John

[dingle]

It looks like the centerline of the axle is the reference point, so it shouldn't change with the diameter of the bearing journals.

Berry

[Ian Vincent]

I have recalibrated it against the centre line of the axle so as Berry says, it is independent of the diameter of the journals.

 

Rgds Ian

[TriumphV8]

I would not go that way at all.

Reason is that modern CWP are remanufactured.

I wonder if they keep that measurement exactely.

 

Referring to TR6 I can say modern CWP have a different way teeth.

Old was Gleason if I am right, new is Oerlikon.

New have much more teeth working together at a time

so they can resist much more power.

Can be seen in my V8 where I have it now more than 9 years in use.

It does not make sense to keep the old parts.

 

With the new parts I start with the big shim at the pinion wheel.

Normally only minor changes must be made later and I always would

take an imprint at the crown wheel several times to get it perfect.

 

So its a nice tool but not required and no substitue for normal setting of CWP.

[Ian Vincent]

I would not go that way at all.

Reason is that modern CWP are remanufactured.

I wonder if they keep that measurement exactely.

 

Referring to TR6 I can say modern CWP have a different way teeth.

Old was Gleason if I am right, new is Oerlikon.

New have much more teeth working together at a time

so they can resist much more power.

Can be seen in my V8 where I have it now more than 9 years in use.

It does not make sense to keep the old parts.

 

With the new parts I start with the big shim at the pinion wheel.

Normally only minor changes must be made later and I always would

take an imprint at the crown wheel several times to get it perfect.

 

So its a nice tool but not required and no substitue for normal setting of CWP.

My starting point has to be the dimensions in the workshop manual. After that I check the mesh pattern with engineers blue and adjust accordingly.

 

Rgds Ian

[Colin Fairhurst]

Hi Ian,

I have sent you a PM regarding the bearings.

 

Regards, Colin

[Lebro]

Ian.

 

All done, will post later ion the week.

 

Bob.

 

Edited December 26, 2017 by Lebro

[Ian Vincent]

Youre a star Bob. Now Ill have to go out in the garage and remove the back axle.

 

Thanks a stack.

 

Rgds Ian

[Lebro]

On it's way

 

Bob.

 

P.S.

 

I presume you did not want the swarf returned to you - there was a lot of it !!!

Edited December 27, 2017 by Lebro

[Ian Vincent]

You are correct Bob, you can keep the swarf.

 

Rgds Ian