I received some glance tools free. They r brand new. I want to turn 304 stainless but they struggle. Will any CCMT 21.51 of the same shape fit on the tools. Basically is CCMT 21.51 a standard that will fit on any tool that accepts that size. I am looking for a better quality cutter. Also any suggestions on good coated indexable inserts. Thanks
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CCMT
- Thread starter metaldesign
- Start date
What do you mean by "struggling"? Bad finish? Broken insert? What kind of machine are you running on?
The inserts you have are 80 degree diamond inserts (the first C), with 7 degree relief (that's the second C), and a chip breaker (the final T). The type of holder you have will dictate what inserts you can use. Specifically, the inserts with relief built in are usually held "flat" in the older. If that is what your holder is like, you are going to need another insert that also has relief built in (anything other than "N" in the second space). If your holder is holding the insert at an angle, then these are probably not the best inserts for that holder (your are likely gonna break/chip them, especially on something like stainless).
Depending on what you mean by "struggling", you might choose a different insert type. The type you have is (I believe) used for finish work, so, may not stand up well to heavy material removal. Another thing to consider is that carbide likes really high surface speeds, what is the stock diameter, and RPM?
The inserts you have are 80 degree diamond inserts (the first C), with 7 degree relief (that's the second C), and a chip breaker (the final T). The type of holder you have will dictate what inserts you can use. Specifically, the inserts with relief built in are usually held "flat" in the older. If that is what your holder is like, you are going to need another insert that also has relief built in (anything other than "N" in the second space). If your holder is holding the insert at an angle, then these are probably not the best inserts for that holder (your are likely gonna break/chip them, especially on something like stainless).
Depending on what you mean by "struggling", you might choose a different insert type. The type you have is (I believe) used for finish work, so, may not stand up well to heavy material removal. Another thing to consider is that carbide likes really high surface speeds, what is the stock diameter, and RPM?
I have a Grizzly 11X26 lathe. The bits do not cut was easily as they do on steel. I understand this> "The inserts you have are 80 degree diamond inserts (the first C), with 7 degree relief (that's the second C), and a chip breaker (the final T)." However I didn't realize they were finishing. That makes sense but the are not that smooth either. I was at 350rpm and had to go slower with boring. My initial question is really simple, this one specific tool uses a CCMT 21.51 insert. Yes, it has a built in relief. Will any BRAND CCMT 21.51 insert work or are different brands different.
Second is 1.25" 304 stainless rod at 350rpm.
Second is 1.25" 304 stainless rod at 350rpm.
DMS,
Do you happen to have a good reference chart that describes the Alpha-code for inserts and holders? I once had a good reference but it wasn't downloadable and then, lost all my browser bookmarks -so now I'm w/o a good reference on this. I use mainly carbide for all my work and tend to utilize the same 5-6 different inserts that work well for me. Still though, it's good to have a handy reference...
Metaldesign,
In your shoes, I'd probably spin that piece around 450 and possibly go up from there if it still didn't look good. Also, stainless likes auto-feed -not hand feed because feed inconsistency shows up like a sore thumb. Stainless fights back a little more than low carbon machining steel and it can take the heat of extra spin no problem. If you continue to have problems, get back with us but do tell us more about the setup.
Ray
Do you happen to have a good reference chart that describes the Alpha-code for inserts and holders? I once had a good reference but it wasn't downloadable and then, lost all my browser bookmarks -so now I'm w/o a good reference on this. I use mainly carbide for all my work and tend to utilize the same 5-6 different inserts that work well for me. Still though, it's good to have a handy reference...
Metaldesign,
In your shoes, I'd probably spin that piece around 450 and possibly go up from there if it still didn't look good. Also, stainless likes auto-feed -not hand feed because feed inconsistency shows up like a sore thumb. Stainless fights back a little more than low carbon machining steel and it can take the heat of extra spin no problem. If you continue to have problems, get back with us but do tell us more about the setup.
Ray
304 SS runs fairly well at 250 sfm with carbide inserts. HSS drilling keep it under 40 sfm and HSS milling at 60. Try 750 rpm @ .006 per rev and see how that goes. The CCMT is a standard insert and should be a match for your holder. Seco inserts are good but any of the big name brands will work well. The insert grade will be the key to your success. Use a grade similar to Seco's F40 for 304. They are different by supplier but the CCMT size will be the same when ordering. What kind of turning are you doing? OD? Depth of cut?
Sorry for running off at the mouth 
As others have mentioned, yes, as long as you get the same insert type and IC size, they should fit your holder.
You may play with depth of cut. Stainless has a tendency to work harden if you take light cuts, which can just make things worse.
@Ray C
I have been using this
[link]http://carbidedepot.com/formulas-insert-d.htm[/link]
KBC also has a similar chart in their full catalog, takes a bit of searching for though.
As others have mentioned, yes, as long as you get the same insert type and IC size, they should fit your holder.
You may play with depth of cut. Stainless has a tendency to work harden if you take light cuts, which can just make things worse.
@Ray C
I have been using this
[link]http://carbidedepot.com/formulas-insert-d.htm[/link]
KBC also has a similar chart in their full catalog, takes a bit of searching for though.