RampantWolf
Classic Car Dealer
Re: 4l80e input shaft Group Purchase
Hi everyone,
First I would like to thank Bruce for organizing this project and also a big thanks to all who have shown an interest.
I've been working with Bruce to design and manufacture the transfer shaft for the 4L80 modification.
I'm sure everyone is interested in what has been done so far. You have probably seen the CAD model I put together after getting my hands on a previously made transfer shaft. That's a relatively easy thing to do since I'm just copying a previous design. We have borrowed a shaft from a previous manufacturing run from a fellow SyTy member that Bruce will have to acknowledge in another post. From this shaft I have gained a lot if design intent however I can't assume that it was done correctly and just simply copy it. That would be irresponsible.
First thing we did was open a transfer case Bruce had laying around. Grab the stock shaft and compare all dimensions with the borrowed shaft. We checked that the borrowed shaft would both in the transfer case as well as slide on the output shaft of a 4L80 transmission. The stock shaft is designed for the 700R4 which has a different spline count. Well it did fit so it does appear that the borrowed shaft be a direct replacement for the stock shaft. It was by no means a perfect copy however it did assemble into the transfer case perhaps with a little but snugged fit than the stock. Is that a good thing...I don't know.
The next thing we had to sort out and that was the material. I was told it was called M300 which after and that it is used in aircraft landing gear and after much research on the internet and calling metal alloy producers I found out it is called 4340 "modified". It is NOT just normal 4340.
A concern we had was to check that it was designed properly the first time and that it has the right dimensions with acceptable tolerances. A lot if time has been spent interviewing the OEMs that manufacture the spline shafts for the Detroit auto makers and the makers of spline measuring gauges. It turns out that tolerances are pretty loose on OEM parts and that the spline design varies from each shaft manufacturing run. I suppose at stock hp manufacturing precision is less of a concern than for someone spending $500 for a high performance part that I've been told needs to be able to handle well over 1300hp.
The splines: there is a lot if science that go behind spline design and again if we were making a stock replacement part their design could be simple but we aren't and that complicates things a little. Thanks to DB Rods and Minis, a speed and chassis shop in Taylor, Tx we got some really nice close up pictures of the spline profiles.
This week I have been designing fixtures to hold the parts while being manufactured. I have to also design and order two custom tooling for the outside and inside splines. When I say design I mean to say that I make a 3-D CAD model in SolidWorks then write a machining program for the CNC using MasterCAM.
We obviously didn't make the cryo deadline but rest assured that we are making progress and will be cutting parts real soon.
I will keep you all updated. If you have any questions please feel free to ask.
Markus
Hi everyone,
First I would like to thank Bruce for organizing this project and also a big thanks to all who have shown an interest.
I've been working with Bruce to design and manufacture the transfer shaft for the 4L80 modification.
I'm sure everyone is interested in what has been done so far. You have probably seen the CAD model I put together after getting my hands on a previously made transfer shaft. That's a relatively easy thing to do since I'm just copying a previous design. We have borrowed a shaft from a previous manufacturing run from a fellow SyTy member that Bruce will have to acknowledge in another post. From this shaft I have gained a lot if design intent however I can't assume that it was done correctly and just simply copy it. That would be irresponsible.
First thing we did was open a transfer case Bruce had laying around. Grab the stock shaft and compare all dimensions with the borrowed shaft. We checked that the borrowed shaft would both in the transfer case as well as slide on the output shaft of a 4L80 transmission. The stock shaft is designed for the 700R4 which has a different spline count. Well it did fit so it does appear that the borrowed shaft be a direct replacement for the stock shaft. It was by no means a perfect copy however it did assemble into the transfer case perhaps with a little but snugged fit than the stock. Is that a good thing...I don't know.
The next thing we had to sort out and that was the material. I was told it was called M300 which after and that it is used in aircraft landing gear and after much research on the internet and calling metal alloy producers I found out it is called 4340 "modified". It is NOT just normal 4340.
A concern we had was to check that it was designed properly the first time and that it has the right dimensions with acceptable tolerances. A lot if time has been spent interviewing the OEMs that manufacture the spline shafts for the Detroit auto makers and the makers of spline measuring gauges. It turns out that tolerances are pretty loose on OEM parts and that the spline design varies from each shaft manufacturing run. I suppose at stock hp manufacturing precision is less of a concern than for someone spending $500 for a high performance part that I've been told needs to be able to handle well over 1300hp.
The splines: there is a lot if science that go behind spline design and again if we were making a stock replacement part their design could be simple but we aren't and that complicates things a little. Thanks to DB Rods and Minis, a speed and chassis shop in Taylor, Tx we got some really nice close up pictures of the spline profiles.
This week I have been designing fixtures to hold the parts while being manufactured. I have to also design and order two custom tooling for the outside and inside splines. When I say design I mean to say that I make a 3-D CAD model in SolidWorks then write a machining program for the CNC using MasterCAM.
We obviously didn't make the cryo deadline but rest assured that we are making progress and will be cutting parts real soon.
I will keep you all updated. If you have any questions please feel free to ask.
Markus
