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2014 POTD Thread Archive
- Thread starter Smudgemo
- Start date
- Joined
- Jun 15, 2013
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- 1,199
chuckorlando, heres an action shot of my favored ccmt holder, equipped with a Kennametal KC850, 21.52, the cut is 4140 steel,1.5" dia, turned ground, polished. .050 DOC, .0042 feed, around 600rpm. the finish is absolutely amazing, rainbowescent, very pretty, all my holders are currently 1/2" but I plan on getting some XL holders so I can get some 3/4 holders for more variety and better selection of holders that aren't available with 1/2" holders. I run a BXA post on my Atlas 12"
- Joined
- Nov 24, 2013
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- 1,791
Awesome. I have watched abom use them ccmt for a while. I think I need a few. I have been using tt's and they do ok. But I want to try some other styles.Looks like the ccmt might have more nose radius then the diamonds or triangles. Maybe not though
- Joined
- Jun 15, 2013
- Messages
- 1,199
Well you can order with different nose radius, a 21.52 is more rounded, for medium to finish machining, a 21.51 has a sharper or smaller radius and is for finish machining. Sandvik was really helpful on the phone helping me decipher the codes of those numbers lol. Sandvik will also send you a sample of the cg432 (I think) inserts, they sent me a pack of two ccmt 32.52 for my larger boring bars. I think you can even get 21.50 inserts which have a very sharp radius. Those numbers apply to both dcmt and ccmt, and I think all others too.
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- Jun 14, 2014
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- 410
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- Nov 9, 2010
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- 306
What is the easiest method you have found for cutting inside the foot and getting it to stay on? I have several that need new ones as well.
- Joined
- Sep 3, 2012
- Messages
- 311
chevydyl,
Thats awesome!
I have a Cman/Atlas 12" lathe with AXA post & have been told, (here) that the 12 " is not "robust " enough to handle indexable tooling ???
I need to do some research to understand the acronym lingo
Also If you would suggest a list of your favorite tooling, I'll just get the stuff at Sharis
Thanks for your time with this
ed
- Joined
- Jun 15, 2013
- Messages
- 1,199
Shars has a 7pc set, not sure how big of holders the AXA holds but they have what you need, the parting/grooving holder that comes with it is junk, broke it lol, the threading holder that came with it, I broke the insert on ALUMINUM!!! but the rest of the holders are great in the set. I ordered some TiN inserts from them with good luck, but since you can find name brand at decent prices that's what I'd do. Call Sandvik tell em what your cutting and they'll help out. Shars has "crap, better, and good" tooling I also bought their boring bar set that uses ccmt inserts 4pc set up to 3/4 " bar.
Most of what I was told was that indexable wasn't necessary, a good sharp hss tool would be more than enough, don't waste your money on carbide, well taking 20 mins to grind a fresh 3/8 bit is a waste of time lol. Although there is that, one cut where carbide holders either won't fit, or won't reach, or where your qctp is too large. Always keep your lantern, and always keep some hss bits around. I posted earlier in this thread where my bxa post was in the way and I had to blow the dust off the ol lantern and grind a special 1/4 in bit to get the job done. Had I sold the lantern post I would not have been able to do that job
Most of what I was told was that indexable wasn't necessary, a good sharp hss tool would be more than enough, don't waste your money on carbide, well taking 20 mins to grind a fresh 3/8 bit is a waste of time lol. Although there is that, one cut where carbide holders either won't fit, or won't reach, or where your qctp is too large. Always keep your lantern, and always keep some hss bits around. I posted earlier in this thread where my bxa post was in the way and I had to blow the dust off the ol lantern and grind a special 1/4 in bit to get the job done. Had I sold the lantern post I would not have been able to do that job
- Joined
- Jun 15, 2013
- Messages
- 1,199
Another thing to note, the size of the insert and the chip breaker, you don't want to use big 432 size insert because these lathes just simply cannot take deep enough cuts to use the chip breaker right, you get heat buildup and wear out the edge of the insert. In that pic above that .050 was a good cut, but I took it to .060 and it was like that insert was doing what it was supposed to do, chips were flying everywhere, blue hot chips, just like it was designed to do, to get the heat out with the chip instead of leaving it all in the work and on the insert. Personally I think that's about the max for my lathe, broken gears are a pain. Imo I think the 21.5 insert is the right size for general turning on the C/A 12"
