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Help Needed Identify Carbide Inserts Needed, and How to Keep Them Organized

dalmatiangirl61

Diamond
Joined
Jan 31, 2011
Location
BFE Nevada/San Marcos Tx
I've spent several hours trying to figure this out on my own, but not making any progress. I have some Kennametal boring bars that need inserts, they did not come with any so not sure what they use other than triangular inserts. So I know they will start with a T, but lost after that, no idea if next letter should be N (neutral) or P (positive). Part #'s on bars are C10S-KTFPR2, and C08-NELL05, google shows these for sale, but no info found on insert P#'s. How do I search by tool P# to find correct insert, or just plain help needed identifying the correct inserts.

How do you keep inserts organized so when you need a new one you don't have to open 20+ boxes looking for the right one? I'm thinking engrave/etch each tool with a number, and organize the inserts to match that number, maybe there is an easier way? Suggestions/ideas needed.

Edit: Correction, I think the C08-NELL05 boring bar uses a diamond shaped insert. No idea where to start on finding that one.

Edit again: In the triangular inserts a TPG322 is too large, and TPG221 is too small, what is inbetween those sizes?
 
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The C10S-KTFPR2 should take a a TPG-221. Wonder why it does not fit?? ... modified?
Not modified, basically new unused old surplus, maybe I just thought the insert should protrude a little further, I'll check again. I picked up these bars back in the 90's, USAF surplus, used the smaller ones, but never got around to using the larger ones, their time has now come.

I saw a link somewhere on here in the past on how to decode insert P#'s, not finding it now, can someone please repost that link, just purchased a shload of lathe tool holders and inserts, I now have the proper motivation to study that.
 
check at the front of the catalog that I posted the link to above. it describes all of it. they also have the inserts for the npl bar. though i should tell you they do not repeat well and are pretty much a crappy geometry to bore with. you can pick up cheap ccmt steel boring bars on ebay that will out perform either of those. I have two brand new carbide bars that take the inserts and have inserts to boot, yet they still are not worth busting out. a screw in bar is much better than the top clamp. Chips hit it. plugs the bore. blah blah blah. If you must give them a shot the kennemetal insert number is npl 52 for .03 radius. npl51 for .016 rad and npl 50.5 for .008 rad. so just order a npl51 k68 for non coated or kc850 for coated. I doubt they come in any modern coating.
 
I see boring bar identification on page 14, not seeing insert identification chart. Found some affordable NPL51 LP25, what do those last 4 digits mean, or point me to a chart. As long as I've held on to these, might as well give them a try.

Edit: Poking around internet I found an insert decoder at carbide depot. Lets see if I get this right
N= Shape 55 degree parallelogram, or is that 55-1/2 degree?
P= Clearance/Relief Angle 11 degrees
L= tolerance (too much info to type)
- = skip N/A
5= size (too much info to type)
1= Thickness, either 1/16" or 5/64" ???
L= wiper lead angle, 75 degrees ?
P= wiper clearance angle, 11 degrees ?

No idea what that last 25 stands for.
Is any of that above correct?
 
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They are 55 degree parallelogram. http://www.tools-n-gizmos.com/info/Insert_ID_Kennametal.html shows todays iso system for insert identification. As far as Kennemetal is concerned that is. The npl and npr were invented before the iso system was established. most likely the last 4 digits you mentioned are most likely the coating and or grade of substrate carbide. one other thing is even though there is a iso system, very infrequently do all manufacturers follow it to a T. ( they all think they are the only game in town. ) Best thing you can do is pick a manf. and stick with them when possible or find insert geometry that the majority of companies all agree on, cnmg, dnmg, tcmt, ccmt, cpgm, everyone makes them so availability is huge. Sorry to drag on.
 
I ordered some of the NPL51 inserts, NOS made in USA. Are these the wrong size, it barely protrudes past RH side of the bar, and the head of the bar has a point that protrudes past the cutting edge of the insert????
 

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You either have a RH insert in a LH bar or the opposite. Turn the insert upside down and see if it lines up, which I bet it does. If so, that means you need the opposite hand insert.

Boy, don't you love this? This stuff will drive you insane! I don't know how many times I've gone through the exact same thing you are going through.
I have several old tooling catalogs that I've kept over the years that have been big help to me trying to find inserts, seats, screws, and clamps.
 
I think its a LH bar, it cuts on RH side and is for use running the chuck backwards so its easier to see what you are doing.

OK, flipped insert over and turned it sideways, that fits the profile of the head better, but cutting edge is on the bottom, and the ridges on what should be the top of insert are not letting it sit flush. So I'm thinking its the wrong-handed insert. Any idea what correct insert would be?

Edit: Would it be the NPR inserts mentioned in post #10? Looking at some on ebay and thinking they look right.
 
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I think its a LH bar, it cuts on RH side and is for use running the chuck backwards so its easier to see what you are doing.

OK, flipped insert over and turned it sideways, that fits the profile of the head better, but cutting edge is on the bottom, and the ridges on what should be the top of insert are not letting it sit flush. So I'm thinking its the wrong-handed insert. Any idea what correct insert would be?

Edit: Would it be the NPR inserts mentioned in post #10? Looking at some on ebay and thinking they look right.

Yep.
 
I apologize for recommending the npl. I figured since it was a boring bar it used left hand inserts. Those right hand variants work good in gang style machines as turning tools. Or obviously spin in reverse and turn bar upside down
 
I apologize for recommending the npl. I figured since it was a boring bar it used left hand inserts. Those right hand variants work good in gang style machines as turning tools. Or obviously spin in reverse and turn bar upside down
I probably should have mentioned it was a RH bar, but since most inserts seem to work both ways, it did not occur to me.

So what is difference between NPR and NPGR? Decoder chart shows 3rd digit G as single sided, did they just leave that letter out on NPR because when you look at it, it is obviously single sided? Am I safe in assuming L and R indicate left and right?
 
From Kennametal catalog 4010:

NPGR is "precision ground". The R/L will be at the end of the description: NPGR51R, NPGR51L.

NP is the base for utility inserts. Lots of variants. NPR/L, NPR/L-F, NPR/L-N, NPR/L-33, NPR/L-R, NPR/L/-13M, NPR/L5M, NPR/L 505-, NPR/L 508-
 








 
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