Recutting Keyways - How is it aligned in the mill?

[Jake M]

I'm looking at that and I'm thinking......

If I were a machinist long ago, pre-automated manufacturing days... There's two keyways in each shaft. I'm betting that the odds are very high that the two key slots were done in one setup... Maybe you could indicate off of the one, to pick up where the other one was? You do have a second example to test the theory with an indicator, before you do anything with a cutter....

.02

 

[David2011]

I'm looking at that and I'm thinking......

If I were a machinist long ago, pre-automated manufacturing days... There's two keyways in each shaft. I'm betting that the odds are very high that the two key slots were done in one setup... Maybe you could indicate off of the one, to pick up where the other one was? You do have a second example to test the theory with an indicator, before you do anything with a cutter....

.02

I never considered the obvious. Guess it was too obvious. The plan was to hold the shaft in a 5C collet by the smooth shank between the threads and the shoulder. I could back off just a little and have room for an indexing pin there. Good idea! I had planned on supporting the gear end of the shaft with a machinist's jack and that remains viable. The cuts are not going to be heavy.

When I machined the remaining key out of two of the gears a few days ago I found that the original bronze keys were originally only 1/4" wide. I think that as long as the shafts are correctly centered in the mill and a 9/32" pin will enter the slot fully it's going to be close enough. Last Wednesday we cut new female keyways where the male keys were. The Battleship Texas Foundation sprung for a proper broaching tool from McMaster. It was my first attempt at broaching slots and it worked beautifully. We didn't have a big arbor press so had to do it on an electrically powered hydraulic press which was a little intimidating at first but by only going 2"-3" at a time and them backing off the broach stayed centered under the ram. Gotta get out in the shop today and finish this job.

 

[Batmanacw]

I never considered the obvious. Guess it was too obvious. The plan was to hold the shaft in a 5C collet by the smooth shank between the threads and the shoulder. I could back off just a little and have room for an indexing pin there. Good idea! I had planned on supporting the gear end of the shaft with a machinist's jack and that remains viable. The cuts are not going to be heavy.

When I machined the remaining key out of two of the gears a few days ago I found that the original bronze keys were originally only 1/4" wide. I think that as long as the shafts are correctly centered in the mill and a 9/32" pin will enter the slot fully it's going to be close enough. Last Wednesday we cut new female keyways where the male keys were. The Battleship Texas Foundation sprung for a proper broaching tool from McMaster. It was my first attempt at broaching slots and it worked beautifully. We didn't have a big arbor press so had to do it on an electrically powered hydraulic press which was a little intimidating at first but by only going 2"-3" at a time and them backing off the broach stayed centered under the ram. Gotta get out in the shop today and finish this job.

Sounds like you are doing great. I usually back off every inch and let the broach spring free, but I'm a coward. Lol!.

 

[gard]

This is a good job for a shaper also

 

[Firstram]

Sounds like you are doing great. I usually back off every inch and let the broach spring free, but I'm a coward. Lol!.

Same thing here, I just bump it through!

 

[David2011]

Sounds like you are doing great. I usually back off every inch and let the broach spring free, but I'm a coward. Lol!.

I backed off every couple (meaning 2) inches for the same reasons.

 

[David2011]

This is a good job for a shaper also

If you have one. I have a full sized mill, 13x40 lathe, 11x26 lathe, 10" table saw with a router table on an extension wing, jointer, planer, drill press, bench sanders and grinders, a free standing router table, a 12" compound miter saw and two benches in a 19'x20' shop. Not much room for walking; much less a shaper. Doesn't mean I wouldn't like to have one though. I would like to have a surface grinder, too.