VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Tap and die size for a 1928 front and rear axle

I am confused about the type of tap and die to use on a 1928 Chevy. The person who owned this used a grinder to cut the nuts off the axles. I have thread damage. What are the thread size and any recommendations as to where I can purchase the correct tap and die for the axles? Thank you for your help.

Which nuts are you specifically referring to? Are you talking about the ones that are on the square u-bolts that hold the axle to the springs? They might be 9/16"-18 like the king pin bolts and nuts along with the tie rod end bolts, at least that's what they are on my 28 truck. I'd want to double check before I swear by it that the u-bolts are the same.

HI David,
I should have made my question clearer. I am talking about the front wheel spindle threads, and the rear wheel hub threads. All these threads are damaged from the previous owner taking a grinder to cut the frozen nuts off. I tried to measure the threads with a thread gauge and came up with a 3/4 -16 National Fine, but the die is too large. Is this a metric thread?

Well, I have to eat humble pie on this one. I went to my local hardware store, and they have a good selection of taps and dies. I bought the wrong die.
National Standard Taper Pipe Threads Size NPT Chart

Engineers Edge
https://www.engineersedge.com › hardware › taper-pi...
The taper rate for all NPT threads is 1⁄16 (3⁄4 inch per foot) measured by the change of diameter (of the pipe thread) over distance.

All taps and dies are not created equally!!

Well I guess I'll be the one to say it. Depending on how badly the hubs/axles are damaged, I would be inclined to replace them rather than running a die over questionable threads. Those threads are very hard and if you don't break your die first, you're trusting that repair with your life.

The rear axle threads are actually pretty soft. If you cannot find the right die, contact some of the older tool suppliers possibly on the model t forum and ask for a thread file with a 16 thread per inch pitch. Usually they are square and have 4 different thread pitches on them. Some others are a little bigger and have 8. It will be fairly expensive to replace all the axles and spindles. Handy to have around.

Go on Ebay and search for outside thread chasher....you can get one used or new with multiple dies for $35 - $50. They come with 20 different thread sizes. (comes with five 4 sided cutters) It's like having 20 large thread dies.

Here is the OLD tool just for your problem. Contact me if you need it. bwbugay@aol.com