Input vs mainshaft different diameters

[Chris59]

Hello guys, 

I'm playing with a Tr6 gearbox, to convert it to overdrive, using a saloon donor box, as many of you have done previously.

My problem is : the mainshaft diameter, where it get in the input shaft needle roller bearing is smaller than the "non overdrive" mainshaft (who's .875" apparently).

Is there a sort of sleeve to fit in between ?

I was thinking of 145008X, but the one I get from a supplier is far to big 

Thanks in advance for your help, 

 

Edited March 18, 2023 by Chris59

[dingle]

Chris-I did that job many years ago. Since I have a lathe, it was an easy job to make a sleeve. I don't know if one is available from a supplier. Perhaps you can find a "friend" with a lathe to make one.

Berry

[Chris59]

1 hour ago, dingle said:

Chris-I did that job many years ago. Since I have a lathe, it was an easy job to make a sleeve. I don't know if one is available from a supplier. Perhaps you can find a "friend" with a lathe to make one.

Berry

Hi Berry, thanks for your reply.

How did you made this and with what kind of material ?

It could be far from simple, as the thickness of the sleeve will be very low, less than 1mm if my memory is good : the other problem is that the needles will roll directly on the sleeve, so a very special metal is necessary (sorry for my rather poor English !).

 

Edited March 18, 2023 by Chris59

[BlueTR3A-5EKT]

I think the sleeve is available commercially.  Ask Peter Cox

https://petecoxsportscars.co.uk/spares-shop/ols/categories/consumables

 

[dingle]

Chris-The bearing I used was a Torrington BH 1412. It is a drawn cup bearing, which means that the needle rollers ride on the cup, not the sleeveThe OD is 1.1875". The sleeve was made from mild steel since it was not a bearing surface. I think the input shaft bearing pocket was enlarged slightly to remove wear and to provide a thicker walled sleeve. The bearing surface of the input shaft was very hard and required carbide tooling and very low speed.

Berry

[Chris59]

2 hours ago, BlueTR3A-5EKT said:

I think the sleeve is available commercially.  Ask Peter Cox

https://petecoxsportscars.co.uk/spares-shop/ols/categories/consumables

 

Thanks Peter, I was already thinking that Tom (Peter's son, if I'm not wrong) could be able to help, he's knowing his stuff.

Edited March 18, 2023 by Chris59

[Chris59]

35 minutes ago, dingle said:

Chris-The bearing I used was a Torrington BH 1412. It is a drawn cup bearing, which means that the needle rollers ride on the cup, not the sleeveThe OD is 1.1875". The sleeve was made from mild steel since it was not a bearing surface. I think the input shaft bearing pocket was enlarged slightly to remove wear and to provide a thicker walled sleeve. The bearing surface of the input shaft was very hard and required carbide tooling and very low speed.

Berry

Berry, the sleeve I need is to to be fitted inside the bearing, so BH1412 needles will run directly on the sleeve  

[dingle]

Chris-It looks like we took approached the problem from different directions.

Berry

[Chris59]

13 hours ago, dingle said:

Chris-It looks like we took approached the problem from different directions.

Berry

Me think the problem was different in your gearbox, ie the main shaft lip was .875", this is corresponding to BH1412 cup needle bearing inner diameter.

BTW, the solution might be to reduce the input shaft inner diameter, and use a 150989 open needle bearing : that's some food for thoughts !

Edited March 19, 2023 by Chris59

[peter clarke]

I put an oversize needle bearing with correct o/d in the input and had the shaft ground down to suit the inside of the bearing. about 30 thou off the diameter 

[Chris59]

10 hours ago, peter clarke said:

I put an oversize needle bearing with correct o/d in the input and had the shaft ground down to suit the inside of the bearing. about 30 thou off the diameter 

Hi Peter, thanks for your reply.

Weren't you afraid of removing the hardness from the shaft ? I know 30 thou is not a lot, but the risk do exist, don't you think ?

Could you please give me the reference and/or dimensions of the needle bearing used ?

 

Edited March 19, 2023 by Chris59

[peter clarke]

Details lost with time. Easier and quicker to grind the shaft spigot down to new size. Thought the shaft was all the same material with no special hardening treatment to spigot. My o/d box has now done approx 40000 kms no issues.

[dingle]

16 hours ago, Chris59 said:

Me think the problem was different in your gearbox, ie the main shaft lip was .875", this is corresponding to BH1412 cup needle bearing inner diameter.

BTW, the solution might be to reduce the input shaft inner diameter, and use a 150989 open needle bearing : that's some food for thoughts !

Chris-You are right. I misread your first posting. My OD mainshaft pilot was .875" and the pilot in non OD mainshaft was about .833"

Berry

[Chris59]

1 hour ago, peter clarke said:

Details lost with time. Easier and quicker to grind the shaft spigot down to new size. Thought the shaft was all the same material with no special hardening treatment to spigot. My o/d box has now done approx 40000 kms no issues.

I made some search, it could be TA2120, outer diameter is 29mm (for 1.125" input shaft ID), inner is 21mm (for .833", ie 21.16mm mainshaft lip).

[Chris59]

1 hour ago, dingle said:

Chris-You are right. I misread your first posting. My OD mainshaft pilot was .875" and the pilot in non OD mainshaft was about .833"

Berry

No problem Berry. It's far more simple your way, beeing sure one won't remove the hardness from the mainshaft lip.

[astontr6]

On 3/18/2023 at 3:20 PM, dingle said:

Chris-I did that job many years ago. Since I have a lathe, it was an easy job to make a sleeve. I don't know if one is available from a supplier. Perhaps you can find a "friend" with a lathe to make one.

Berry

Speak to ORS they have years of experience of doing this and if I remember, they have a kit . As far as I am concerned they are the top dog in OD's as they worked for GKN and have their machine tools!

Bruce.