How Do You Identify Splines?

[bpimm]

I have a shaft with splines on it and want to cut an internal spline to match, how do I identify what kind of spline it is? I don't have a machinery's handbook yet and Google hasn't helped much.



The major diameter is .680" and the angle seems to be about 90* and there are 23 splines.






I'm thinking of single pointing using the carriage on the lathe or the quill on the mill, the lathe has an indexing ring on the collet adapter but its got 24 positions so maybe a spindexer on the mill would work better.

one thought I had was to turn an extra shaft into a broach, it will be cutting aluminum.

All thoughts and ideas welcome.

Brian

 

[David VanNorman]

I think your idea of useing your spare shaft for a broach might work . Is the parts to go on this shsft to be taken on and off? I would under cut the end to make a cutting edge and try it for a broach.

 

[Billh50]

Not sure if this will help but here is some info.

 

[Bob Korves]

You will need to be able to divide into 23 divisions. That leaves out your 24 space divider and your spindexer (23 does not divide into 360 evenly.) You will need a real dividing head to do the job, along with a shaper or equivalent, to do the job. A broach made from an extra shaft would need to have longer splines than the aluminum material thickness. Shaping the teeth single point manually would be a very slow process for 23 grooves, even if you could divide it evenly. If the fit can be less than precise, you might use that extra shaft as an indexer, somehow held in the left end of the lathe and with an indexing pin to position it. Your arms will be in shape for manual surface grinding by the time you are done with it!

 

[Billh50]

To use the extra shaft you would need to cut off the end threads and relieve behind the spline so you can go deep enough. I would then make it a rotary broach and broach that way.

 

[Wreck™Wreck]

May well be an involute spline utilising the same grometry as an involute spur gear, this will also have a pressure angle.
If so an involute form cutter will be required.

However there are straight sided spline standards.

Different spline designs http://www.arrowgear.com/products/splines.html