Back on the arbor again (no progress yet on the support). I took the picture that BIGPAULY provided and did my best to turn it into a drawing. There are a few questionable areas:
1. Atlas specified both turn and grind diameters for many parts. The diameter of drive ring turn unreadable, I'm reading the grind as 1.365 to 1.363
2. I can't read the width of the drive ring. Other sources show as .400, scaled measurement off the picture is .39(4-7). I have no idea how a fractional dimension that looks simple could end up at .400, but it is consistent.
3. I'm not sure of the minimum diameter of bearing on end. Can't read turn at all or the minimum grind, aim/max appears to be .625
4. The positioning of the drive notches is questionable. I first assumed that the dimension by the flange, and the dimension by the end view were both 1 1/8". That didn't look right at all. I tried 1 1/16" and that looks good.
The notes on the drawing were interesting as well. I think the notes must show what was
previously there. Not an ME, so I don't know the protocol.
The note for 2/23/56 changes the taper rate. The note is .602" or .603" per ft. .5994" per ft. is the standard in Machinery's for #2. #3 is .60235" per ft.
The note for 9/24/48 appears to read E 12 1/8"; 7 13/16"; 1" and appears to relate to the overall length and the active length of the arbor. It would be interesting to see if someone with a really old arbor sees a different length.
Then there's the small end of the taper. On 2/2/42, HEM added a dimension for the small end of the taper for turning. Then on 2/26/51 H. MOD decides it's confusing and removes it.
There also appears to be manufacturing instructions on the left side of the drawing. I was interested in this to see if there were any clues to help me make the arbor. My best translation:
Turn ????dia, 3/4 dia, center, cut reliefs, face, thread, chamfer
Cut off and form end mach #435 spd 460 fd .oo4
Turn, form taper, turn, drill & tap 3/8 and center ( this seems odd, as it would not allow a proper center for the later grinding steps)
Mill keyway mach #254 spd 119 fd 1.2" (sounds like one pass to cut full depth, at 1.2 inches per minute)
Mill driver slots mach #266 spd 172 fd 1.6(4.6?)
Rough grind mach #111
Rough grind mach #363 grind front side of shoulder(this one and the previous one were bracketed together)
Finish grind long step mach #111
Finish grind long step mach #363 (this one and the previous one were bracketed together)
Grind shaft end to size mach #111 or #363
Grind taper to size
Grind shoulder (Clean up) mach #111 or #363
There's no mention of heat treatment in this process. That's one thing that concerned me as I thought about making one myself. I wonder what "#2 S.P. Steel" is/was...
I'd really appreciate any comments the community may have. I've also cheated a bit. I added a .pdf extension to the Atlas Arbor Drawing Copy.dwg file so that I could make a true drawing available if you need that.
Moderators, if that's a big no-no, please delete the file and chastise me appropriately.