BrandonRB
Automotive
- Oct 9, 2019
- 1
Hello,
I'm in need of some help figuring out the correct way to copy a spline. I've searched through a lot of good information here but it seems there are many different standards, including proprietary and even arbitrary ones. So I thought I'd make my first post and see if anyone can help guide me in the correct direction.
The shaft I have is out of a Ford transmission. The measurements I have taken from it are:
Number of Teeth - 24
Outside Diameter - .8315"
Minor Diameter - .762"
Measure over pins - .9341"
Pin diameter - .081"
Photo of the shaft:
Now I have little to no experience with splines/gears but my searching has led me to believe this is a flat root, stub form, involute spline. I could be completely wrong.
So I ran with that and whipped up a model in CAD of an involute gear using a gear generator plug-in. The input data I used was:
Pressure Angle: 30 degrees
Module: .847
Backlash: .003"
After chopping the OD down to the correct size and lifting the root up to match, I machined a test piece out of aluminum. I had to take an extra .002" (radial) off the final product but once that was done it fit into the mating part.
The problem is when I measured the test piece over wires it came out to be .9385" when the original measured .9341". So this tells me the tooth form must be incorrect. If there is a standard out there that would fit this so that I can model it properly I would love to know what it is.
If anyone has any input for me on this it would be greatly appreciated.
Thanks,
Brandon
I'm in need of some help figuring out the correct way to copy a spline. I've searched through a lot of good information here but it seems there are many different standards, including proprietary and even arbitrary ones. So I thought I'd make my first post and see if anyone can help guide me in the correct direction.
The shaft I have is out of a Ford transmission. The measurements I have taken from it are:
Number of Teeth - 24
Outside Diameter - .8315"
Minor Diameter - .762"
Measure over pins - .9341"
Pin diameter - .081"
Photo of the shaft:
Now I have little to no experience with splines/gears but my searching has led me to believe this is a flat root, stub form, involute spline. I could be completely wrong.
So I ran with that and whipped up a model in CAD of an involute gear using a gear generator plug-in. The input data I used was:
Pressure Angle: 30 degrees
Module: .847
Backlash: .003"
After chopping the OD down to the correct size and lifting the root up to match, I machined a test piece out of aluminum. I had to take an extra .002" (radial) off the final product but once that was done it fit into the mating part.
The problem is when I measured the test piece over wires it came out to be .9385" when the original measured .9341". So this tells me the tooth form must be incorrect. If there is a standard out there that would fit this so that I can model it properly I would love to know what it is.
If anyone has any input for me on this it would be greatly appreciated.
Thanks,
Brandon