WTB Change Gears for Metric Threads on a Lodge & Shipley Powerturn

[inwoodcutter]

I know it's a long shot but I'm looking for the 3 change gears that will allow me to cut metric threads on the Lodge & Shipley Powerturn lathe. They are 127, 90, and 64 tooth. I think the DP is 8. Spur cut. These have the four splines in the bore.

Thanks,

Dan

 

[inwoodcutter]

Still looking if anyone has ideas where I could find these?

 

[Zahnrad Kopf]

Shoot me an e if you find no love.

 

[Finegrain]

These are going to be really hard to find or make. The 127 will be >16" diameter. That alone really restricts who could make them. Then the bore splines further complicate things. I could figure out a way to mount blanks this big and cut the teeth with involute gear cutters, but the splines are out of my capabilities, and I'd only be able to do them this big in cast or ductile for the gear material, which might not meet your needs on your Powerturn.

BTW, are you sure these have to be 8DP? It might be challenging to find room in the end gearing for a 16" gear. OTOH, for all I know this is how L&S designed it :-).

Regards.

Mike

 

[inwoodcutter]

.

BTW, are you sure these have to be 8DP?

Regards.

Mike

16" !?!? Yeah I must have looked at something wrong. Got the number mixed up between the lathe and the computer. I'll have to check again.

 

[inwoodcutter]

Ok, went about figuring this a different way. The first time I tried using chordal length, that was stupid. Just measured the diameter of two gears. The 36 tooth is 3.8" and the 72 tooth is 7.4" dia. which should make them 10DP not 8DP.

 

[johnoder]

7.4 divided into 74 = 10

3.8 divided into 38 = 10

The normal way to check

Measure clean burr free OD
count teeth, add two

Divide sum by OD

Example:

2.125 OD
32 teeth

34 divided by 2.125 = 16 DP

 

[inwoodcutter]

Thanks John,

After fine grain raised the alarm I cracked the Machinery Handbook and found those handy charts and formulas......

 

[M. Moore]

So for all us dummies out there does that make the 127 tooth gear 12.9" in diameter?
Still pretty big.

 

[Finegrain]

So for all us dummies out there does that make the 127 tooth gear 12.9" in diameter?
Still pretty big.

Yes, and yes.

Regards.

Mike

 

[inwoodcutter]

Yeah, It's hard for me to believe that I'll have a 13" gear running inside the box.