So, a lot of progress today! First, I decided to get the broaches assembled! There was a little bit of repair to each component necessary, but nothing too bad.
I started with the spindle. The tail was a little oversized, so a little bit of time with a file and some Emory paper made the bearings fit:
Next I looked at the body parts. The bearing fit in nicely, though some deburr process seemed to make a couple of the threaded holes not really work. The 10-32 were the worst (3 of them wouldn't start), but the 1/4-28 had a pair as well. A few minutes cleaning up with a tap made short work of all of these however.
And here is a little layout of how the assembly works. Spindle, thrust bearing/washers, body, bearing, cir-clip.
A little bit of the tapping repair
Spindle and thrust bearing in the bodies:
Then bearings:
Then cir-clip/snap ring or whatever these are called
Next, to the backing plate. 3 of the 4 were fine, but all 4 holes in the other had some weird "step" inside that prevents the bolt from getting through the hole. I used a drill to finish these holes, no problem
And here is the group picture all bolted together!
Next, I got back to my bits. I opted to work on the 1/4" square to try my new strategy of first hand grinding. I marked out the ends with blue and a height guage which got me rough measurements. I ended up getting down to .325 manually;
Then a bit of back and forth on the surface grinder got them just right!
And a picture of all the bits so far!
I have a 4 and 5mm ground, 2 3/8, and 2 1/4 square. I still have to grind the cup end in them, but 6 of 11 at least precision ground (plus the one screw up last week!).