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I'm looking to do a similar thing, but for a dodge application. 29 spline output on the original Getrag 360 transmission, which I'm going to replicate on the Eaton output. How did you determine the gear cutter you used?
 

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Discussion Starter · #63 · (Edited)
Hey Pianoman,

Welcome to 4bt swaps! The cutter is determined by shaft diameter and the # of splines.. And the diameter of your splined shaft may not be full engagement (i.e. smaller diameter), so there is a bit of intuition/guess work involved. There is a standard for splines that you can find in the Machinists Handbook (I hazard that your splines are involute). Most spline cutters can cut a narrow range of diameters/# of splines. I made a test shaft out of aluminum before I cut the Eaton output. What is the diameter of your shaft? I'll see if I can find the reference sites I used.

Cj

And sorry about the slow reply... it's been a couple of busy weeks at work and home.
 

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Hi cj, what I ended up finding out on another forum was that it is a 30deg pressure angle. That was really the first step to selecting the appropriate cutter. From there, the module and # of teeth narrow it down. Finished the shaft yesterday, and the adapter today.

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It's what I do full time out of my garage (machining). This is a project for my cousin, I don't normally do automotive type work. Measured spline over pins to get a pitch diameter sort of reference (not true but close enough for comparison) and made the new spline to match the existing one. Fit exactly the same. Hopefully will be assembling everything Tuesday.
 

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Discussion Starter · #67 ·
My shop is a side hustle for the moment. I do enough work that it pays for power and heating as well as a bit extra. What cutter did you end up buying for the splines? I'll bet the lathe had fun cutting through the hardened exterior of the Eaton output shaft.
 

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Mine started as a side hustle while working full time in a machine shop, and did both for about 6 yrs while acquiring more machines, tools, etc. Finally pulled the trigger last July and went full time. The cutter came from Ashgear, FMF30-125-4. Yeah turning down the hardened spline ate up a few inserts lol!
 
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