OP
DocsMachine
Well-known member
- Joined
- Sep 16, 2006
- Messages
- 1,928
Once again I needed a tool that either wasn't made or I couldn't find. In this case, a 5/8" shank profiling tool for my CNC turning center, that holds a small DCMT 55 degree diamond (shaped) carbide insert. I had one that takes a 3/8" sized insert, but I wanted one that took the smaller 1/4" size, for smaller details. (And I already had a boxful of inserts- why not use 'em?)
So I dug out a chunk of 5/8" cold-rolled, lopped off a section that looked about long enough, faced one end, and put what I thought was a 55 degree point on the end.
Over to the mill for an alignment flat on what was now the "top" of the bar...
And then I milled half the point off.
In retrospect, I should have turned the bar 90 degrees and milled it that way, but hey, I've only been doin' this half my life, I can't be expected to remember everything.
After that, I swapped out the vise for the rotary table, and set the rod up in a couple of V-blocks. This would allow me to machine precise angles in the insert pocket, easily and quickly.
Line it up square to the table travel, zero the table pointer, find the center of the rod...
Crank it over 27.5 degrees, and start milling a pocket, very gingerly with some itty-bitty endmills.
Like so. It's also at this point I realized I might have been off on the compound setting when turning the point.
I think what happened was, the compound has degree marks, but after 90 degrees- parallel to the bed- they're not numbered. I think I miscounted and went 22.5 degrees (past 90) rather than 27.5.
No big, I can fix it, and the tool will still work.
I located and drilled the mounting screw hole for the insert...
And of course realized too late I didn't have a tap for the correct M2.5-0.45 Torx insert screw, so I tapped it to 2-56, which I did have, and is, by blind luck, not only very close to the same thread pitch, but slightly smaller too. At some point I'll make another McMaster order and get the proper tap, lightly retap the hole, and swap to the right screw.
Then, while it was still on the table, I simply turned it to the same angle as I'd milled the insert pocket, and shaved down the sides to match.
A little careful stoning to break the sharp edges a bit, a little gentle beltsanding to smooth some of the machining...
And just because, a good hot scrub and a wipe of Casey's Gun Blue so it kind of matches the other machine tooling.
Maybe not quite perfect, but 100% functional. Next up, I guess now I gotta make another whole tool block...
Doc.
So I dug out a chunk of 5/8" cold-rolled, lopped off a section that looked about long enough, faced one end, and put what I thought was a 55 degree point on the end.
Over to the mill for an alignment flat on what was now the "top" of the bar...
And then I milled half the point off.
In retrospect, I should have turned the bar 90 degrees and milled it that way, but hey, I've only been doin' this half my life, I can't be expected to remember everything.
After that, I swapped out the vise for the rotary table, and set the rod up in a couple of V-blocks. This would allow me to machine precise angles in the insert pocket, easily and quickly.
Line it up square to the table travel, zero the table pointer, find the center of the rod...
Crank it over 27.5 degrees, and start milling a pocket, very gingerly with some itty-bitty endmills.
Like so. It's also at this point I realized I might have been off on the compound setting when turning the point.
I think what happened was, the compound has degree marks, but after 90 degrees- parallel to the bed- they're not numbered. I think I miscounted and went 22.5 degrees (past 90) rather than 27.5.
No big, I can fix it, and the tool will still work.
I located and drilled the mounting screw hole for the insert...
And of course realized too late I didn't have a tap for the correct M2.5-0.45 Torx insert screw, so I tapped it to 2-56, which I did have, and is, by blind luck, not only very close to the same thread pitch, but slightly smaller too. At some point I'll make another McMaster order and get the proper tap, lightly retap the hole, and swap to the right screw.
Then, while it was still on the table, I simply turned it to the same angle as I'd milled the insert pocket, and shaved down the sides to match.
A little careful stoning to break the sharp edges a bit, a little gentle beltsanding to smooth some of the machining...
And just because, a good hot scrub and a wipe of Casey's Gun Blue so it kind of matches the other machine tooling.
Maybe not quite perfect, but 100% functional. Next up, I guess now I gotta make another whole tool block...
Doc.
