# How can I cut splines on a shaft



## bpimm (May 29, 2018)

Hi all,

I need to spline the end of a shaft to accept a sprocket, I have lathe and mill but I don't have an indexer. I have a collet block that I could cut the initial groove but I'm drawing a blank on how to re-index the shaft to cut the strait sides on the remaining teeth. My thought was to cut the groove then index it 30 degrees and offset both ways to cut the sides parallel and to width. 

Would one of the cheap spin indexers work for something like this?

I think it is a parallel key spline, is that correct?

Here is a pic of the sprocket.


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## Surprman (May 29, 2018)

Why not bore out a hex nut to a slip fit on the shaft, loctite it in place and use the nuts sides to index the shaft?  (Heat the loctite to remove the nut when you are done).

Rick


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## stioc (May 29, 2018)

You could use the lathe's spindle as an indexer and perhaps a tool post grinder to cut the slots.

Spindexers are cheap but you'll also need at least a 5c collet or some other way of mounting the shaft to it- depending on the diameter of the shaft.


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## kd4gij (May 29, 2018)

A hex collet block will work for that.


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## Larry Hoy (May 29, 2018)

I have used a spin indexer and a end mill to do this. I would make a trial shaft for practice


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## RJSakowski (May 29, 2018)

A spin indexer would work for six splines.  They index in 1º increments.


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## Ray C (May 29, 2018)

Do you have a V-block and clamp like the one shown?   You can mount it to one end of the shaft, and rotate the shaft in the mill vise, using an assortment of angle blocks (or an angle gage) against the flat edge of the V-block to set the angle with respect to your mill table. 




Ray


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## tjb (May 29, 2018)

I made a splined lead screw for the cross slide on my Harrison M300 lathe.  The lead screw and nut were worn out, but I was able to buy the nut from an individual in the UK.  I bought a piece of LH Acme threaded rod from McMaster-Carr and copied the original.  I used a hex collet block to cut the splines.  If it's necessary to mill the ridges flat, you can do that in  a two-step process.  First, cut the splines on the hex collet block 'flat' sides, then the ridges on the 'points' (or vice-versa).  It turned out fine.  Here are some pix of the old and new side-by-side:






Hope this helps.

Regards,
Terry


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## benmychree (May 29, 2018)

So far as milling the parallel sides of a straight sided spline, I use two ganged slitting saws spaced apart on the arbor to the correct width; I cut the required number of slots, then rotate the blank to half the distance of the first series of cuts, then use a plain milling cutter of a width that will remove the intervening material between the flanks of the flats of the spline.  As far as indexing the spline, a spin index or a collet block would do the job.
I have also used spline milling cutters that cut the full form of the spline; the spaces between the tooth flanks. These, I got from Ash Gear.


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## savarin (May 29, 2018)

maybe you could knock up something like this
https://www.hobby-machinist.com/thr...-did-you-do-in-your-shop-today.14637/page-203
message 6089, the change gear is held with an expanding mandrel. I havnt made multiple splines with it but cant see why not with a bit of care.


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## bpimm (May 30, 2018)

kd4gij said:


> A hex collet block will work for that.


Ok I have a hex collet block and can see cutting the 6 grooves but how do you accurately re-index the part so you can cut the parallel sides?

Ok I think  see it... cut the grooves on the top of the shaft then cut the parallel sides with the end of the endmill on the spline sticking out at 90 degrees, then there is no re-indexing needed. Am I seeing that right?


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## kd4gij (May 30, 2018)

You got it 


Sent from my SM-G530T using Tapatalk


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## bpimm (May 30, 2018)

First try fits, a little tight but fits!

Had to touch the sharp corners of the splines with a file.


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## Martin W (May 30, 2018)

Great work,
Cheers
Martin


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## tjb (May 30, 2018)

bpimm said:


> First try fits, a little tight but fits!



A tight fit - that's what you want!  Good work.

Regards,
Terry


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## brino (May 30, 2018)

bpimm said:


> First try fits, a little tight but fits!



Wow! Great Job.

I *never * post my first try.....those usually look like embarrasing rat droppings!

-brino


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## kd4gij (May 30, 2018)

Nice Job.    Well done.


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## royesses (May 30, 2018)

Great job of it. You da man!

Roy


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## bpimm (May 31, 2018)

Thanks Guys, I wasn't expecting it to come out anywhere near that good on a first try, Like Brino said my scrap bin is full of first try's... and seconds... and...

I was having trouble trying to measure and calculate the depth and offsets so I drew the part in Fusion 3D then I got the needed measurements, Then I just followed the numbers and it came out, never expected that LOL. Now hopefully the rest of the project will come out as good.


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## tjb (May 31, 2018)

bpimm said:


> Thanks Guys, I wasn't expecting it to come out anywhere near that good on a first try, Like Brino said my scrap bin is full of first try's... and seconds... and...
> 
> I was having trouble trying to measure and calculate the depth and offsets so I drew the part in Fusion 3D then I got the needed measurements, Then I just followed the numbers and it came out, never expected that LOL. Now hopefully the rest of the project will come out as good.


First try a success AND he's a Fusion 3D expert!  Where did this guy come from?!


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## bpimm (May 31, 2018)

I've been hanging around here mostly reading but I couldn't find the answer that way. Hardly an expert, just fuddling my way through it. I used Alibre for years until they decided to kill the home version so I'm trying to learn fusion.

I do have a new project coming up that I'll probably need a bunch of advise form the masters here on, I'm sure I'll be way over my head. but what better way to learn.


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## tjb (Jun 1, 2018)

bpimm said:


> what better way to learn


Couldn't agree more.


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