Resplining a solid driveshaft

M

motordr

Well-known member
Anyone know what cutter to get in order to cut a 6 spline on a solid drive shaft and where to source it?
 
i did one once. i have machines, but do not claim to be a machinist. if you look close, it was not cut with a beveled mill cutter, but cut with a normal endmill bit, diving down at about 10:o clock, and then move over and do 2 o clock (just guessing) look at it, and you will see the cut from ford left sort of a "w" shape in the spline. i too thought they had a cutter that shape, but no, i believe its done with a straight end mill. perhaps some real machinists can expand
 
I have never cut drive shaft splines, but I have cut axle splines. The axle splines end up like a "V" and use a 45 degree type cutter. I would guess cas3 has it right.
 
i will also add, when i did mine, i cut a small chunk off a junk shaft, and then made a jig that would hold it in line with the shaft to be cut in the vice, and then just copied the cut. no mathematics, just hillbilly machine work. when you get that set up, you can see why the "w" shape is left in the bottom of the groove. the "w" is the remainder of two 90 degree cuts. hope this makes sense, but if you have one, set an end mill bit on the side of a spline, and you will see why the mark is there
 
motordr said:
Anyone know what cutter to get in order to cut a 6 spline on a solid drive shaft and where to source it?
Click to expand...

Measure the spline, then order a cutter to match.
Lots of them on ebay.
As I remember, it is a standard SAE 1 1/8-6 spline.
Check your measurments to see if they match the ones in the Machinerys Handbook for that spec.
 
When we shortened the driveshaft for the '40 rear end into the '29 roadster, the driveshaft shop cut, took a section out the torque tube and driveshaft, and welded them in a lathe. Did not have to cut splines.
 
Its also easy to turn the shaft down to a interference press fit. Press it into the shaft coupler at the pinion end and weld it . Have also seen some done with a slot milled into the side of the shaft coupler for more weld area. I have done a bunch of them this way with no issues.
 
A lot of splines were cut by linear shaper machines back in the day but many were cut by horizontal mills with a purpose built cutters after they became more common. Ford likely had special mills to make the parts quickly. FoMoCo had a lot of very specialized machines & tooling in the early V8 era.
 
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I agree with rotorwrench that they are cut on a horizontal mill.

Bob
 

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So I am just about done building a Columbia for my 32 Ford project. The 34 torque tube has been shortened, the last item is the drive shaft. The problem is OD of the 6 spline adapter is smaller than the ID of the tubular drive shaft. I need a coupler with a larger diameter that I can turn down to be a close fit to tube so I can weld it. I don't really want to put a sleeve in there. What about building up the OD with weld and turning that down to size?
The other cleaner option is to cut down a later solid shaft and re-spline one end, so no welding and no extra parts, keep it simple right?
The major diameter is 1.090", minor diameter .900"
Tooth width about .260" near the pitch circle,
Appears to be American Standard Involuted Spline with 30 degree pressure angle.
Now, what DP gear cutter with 30 degree PA do I need and where can I get it?
I will be doing the machining on my Ram & Turret milling machine.
 
You use to be able to buy a 10 -6 spline adapter coupler that had a larger OD to press into a 34 hollow driveshaft and weld in place. I think patricks sold them.
 
I have just had one done. I was unable to buy the 10-6 adaptor, so we used the standard 6 spline coupler, cut the 10 spline off at the weld, turned the inside diameter of the remaining plug to press fit the new 6 spline coupler in, then welded. Worked great.
Dave h
 
A solid shaft really needs a center damper bearing. They can whip a bit under initial loading. The 10 to 6 adapters used to be the way to go using a fabricated straight tube for the shafting and an old tube type splined front section welded up front.
 
"You use to be able to buy a 10 -6 spline adapter coupler that had a larger OD to press into a 34 hollow driveshaft and weld in place. I think patricks sold them."

This is what I have always done with good results...
 
rotorwrench said:
A solid shaft really needs a center damper bearing. They can whip a bit under initial loading. The 10 to 6 adapters used to be the way to go using a fabricated straight tube for the shafting and an old tube type splined front section welded up front.
Click to expand...


Good point. I use the matching outer torque tube and shorten all of it from the pinion end. When I turn the solid shaft down to press I to the coupler I hold it in the lathe at the spot the carrier bearing rides on because the solid shaft tapers between the very front to the carrier bearing and then tapers again between the carrier bearing to the rear splines. This makes it easier to Install but when you go to respline in ths tapered area you have to remember not to cut the splines as deep as the ends because ths OD is slightly smaller. I have resplined them but prefer the inference press fit and weld it.
 
If you need just one done, Mitchell Overdrive did one for me. Nice work as they do it a lot for their product. You do have to stand in line as they're not always set up to do it.

And, checking shops, they're much more reasonable.

Karl
 
The other problem with resplining a solid ford shaft, is that the splined areas are slightly bigger diameter than the general areas of the shaft. The shaft diameter is bigger where the bearings are, and the rear spline.

If wanting to respline further down the shaft the area would need building up with weld first, then skimming down to the correct diameter and then milled out by one of the methods described above. I suspect Ford may have used two side and face cutters in a gang mill, spaced apart to get the spline width. Still six cuts per end, but better than 12.

I have only dealt with shaft shortening twice, and both times have used a 4 cyl tubular shaft and welded the coupler into the end, using a tubular adaptor due to the difference in diameters.

Mart.
 
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if you lay a straight edge across the end you'll see the sides of spline at 10 and 2 are straight in line with each other. 30 degrees? who cares, they are inline, horizontal so you can do it with your verticle mill. last time i made a jig to hold the piece to copy, but then the jig is in the way for test fitting. next time, i would use the center ford put in the end of the shaft, and drill and tap to hold a small chunk of spline on the end to copy. at the time i could not find any one to do it, even twin city gear said they had no cutter to do that and suggested doing it the old fashion way. welding the coupler would be easier, but you can do it yourself on your mill
 
Yes, the spline teeth sides are parallel, about .270" wide. Lots of good info here. I just did a trial cut, a 3/8 carbide end mill cuts it easily.
The spline end diameter is 1.090". The area I need to spline is 1.040" diameter, results in the .025 reduction in spline height, not enough to worry about.
The shaft diameter is very consistent, with the centre bearing diameter at 1.100"
With a shaft length of 48" I'm not sure how much I need to worry about whip.
In the mean time I have turned down an NOS 6/10 spline adapter to fit the cut down '34 tubular drive shaft. I will take it to a driveline shop for aligning and weld up.
Looking forward to getting the chassis on rubber!
 
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