Cylindrical interference fit?

[great white]

Really nice design and fabrication work.

You mentioned "build myself the broach". For the admiring newbies, can you explain how you get key slots in what appears to be a blind hole? I thought broaches were normally set up to pass thru a hub with a slotted guide bushing. Can you explain how you made the key slots?

It is essentially a blind hole. There is a through hole to bolt it to the end of the transmission shaft, but it's only for a 5/16" bolt. It made no difference for my broaching tool, so it was essentially a blind hole.

My solution was simple; the keyway is 3/16" so I drilled a 3/16" hole in the side of the adapter at the depth my broach would reach. The chips broke off at the hole nice and clean.

The other way would have been to cut a groove inside the piece at the same depth.

As my drive hub was going to be heat shrunk over where the hole was going to be, I didn't have to worry about having a visible hole on the outside once finished. In my case, drilling the hole seemed the simplest, most expedient solution.

 

[TomKro]

That's a nice way to tackle the problem.
Does the broach tend to get stuck if you can't push it through?
I'm guessing the cross drilled hole would provide the opportunity to knock it out if it did get stuck.

Excellent execution to solve a tough assembly problem.

I noticed you're from Nova Scotia. Do you happen to have the scoop on the location of that treasure at Oak Island?