Shop Talk 15: CNMG Inserts & Why I love Them

hey guys welcome back to the shop for another episode of shop Talk today I'm going to continue on talking about carbide inserts we're kind of on a roll with this subject and I and I still got a lot of questions and a little bit of chatter here and there out there on the Facebook pages and people asking questions about different inserts and stuff like that so that's why I continue to go over them but today I wanted to pick out my personal favorite carbide insert that I used for all my general turning and facing and whatnot and go ahead and and show you and that is the CMG insert particularly CN mg 431 432 that size the 400 size of insert so I'm going to show you why I like this insert why it's become my go to insert around the shop and why I like to use those because it covers it covers different tools and different angles that you can use on those inserts different corners and use them all up you know you have another popular one out there is a WN mg which has six corners also known as a trigon insert those are excellent too I've got a bunch of those around here I use both of them but my favorite is a CNM G because you have eight cutting edges on that and for the longest time growing up through the shop I never realized that you could use the other four corners of the insert my dad had never bought the tools for it I just thought you could use the proper turning or corners for turning and facing and they're not discovered in these other tools out there that you can buy to use up all eight corners of a CNM G insert and there's several of them that I don't have there's you looking at in a metal book you know it's like that thick there's a lot of other tools and boring bars that you can buy to use the same insert to be able to use up other the other corners of the insert some of those I would like to acquire eventually so we'll see about that so I'll go ahead and get the camera down here and get you a closer shot again we'll go over the the insert real quick and kind of go over these these tools and why like this insert so to start with we'll just go over the actual insert that we're using again and that is a CNM G 432 what I could be a 1 or a 0 or 3 so see and again we're using this book right here this engineers black book to decode everything so see is your 80 degree rhombic and is your relief angle and that is the relief angle underneath the cutting edge whenever you're when you're talking about relief angles this is a negative break insert negative rake means that it is kicked out an angle if you're looking at this insert in line with the bottom of the tool so if it was straight it would be parallel but you can see that it's it's tilted down that is a negative break insert so these inserts are square on the side there's no relief ground into it if this was a flat ends a flat tool which I can't remember which one that would be you would have to have clearance ground underneath the the carbide insert there underneath the cutting edge so that would clear the work so zero Degree relief angle M has to do with the tolerance with manufacturing 3 to 7 thousandths I think somebody had asked me about that from what I understand is that is a tolerance that manufacturers are given to fall within when they make these inserts size wise you know it has to be within those dimensions right there 3 to 7 thousandths and G is how the the insert is fixed to the tool and the stolid chip breaker and then when you get down to the 432 4 indicates your insert size this is being a half inch inscribed circle half inch and search what I call it 3 is the thickness so these 3/16 and then 2 again as you know radius so two is a 1/32 knows radius a one is a one sixty-fourth knows radius and then let me see we get two a three a three is going to be a 364th radius in it and it just goes up and keeps climbing alright so that's a quick rundown of the insert well let's check out the the tool so these are my five tool holders that I that I commonly use for a CNM G insert and we also have this facing mill here we're going to that just a couple minutes so these two right here this is your this is your right and your left and you would use these for turning and facing on a multi fixed sometimes alternate use it for chamfer and inside/outside this tool right here this one's great for chamfering I use a lot for chamfering or cutting angles just any kind of angle that's not critical on what the angle actually is you can just use this angle that's built into the tool come up and break edges that kind of stuff you can also use it to make undercuts if you've got to turn down an area of a shaft not from the end but somewhere in the middle of shaft these are great for plunging in and then going across and coming back out so good tool for that and then these two over here these are the ones that I haven't shown very much up but I have questions about these so these two inserts right there are the ones as well as this one they use what I like to call the odd corners these are the corners that's used on meat on these tools the corners that we're using are not used on this tool right here okay let me pull one out and we'll take a look so whenever you're turning and facing with a CMG tool you're using these corners right here alright and once those are burned up you typically throw it off into a bin somewhere to collect for carbide scrap whatever but if you have these other tools you can make use of these other four corners right there you know because you have those two and then flip it over and got those too so that's why I like using this insert because you have several tools to use up all eight corners of that alright so these two you know this is a MC LnL and then this one would be at MC Ln R and then mine are all three three quarter shank take the four hundred sighs insert this one right here so you guys are curious MC HNN this one was a one inch shank tool whenever I bought this kind of metal did not offer this tool in a three quarter shank so I had to buy them one inch shank and mill it down so I got it milled down to fit my holders right there and then these two they do offer in a three quarter shank so the one that I use all the time would be a MC k NR 1 to 4 B and then this one is actually brand new I've never used it but I pulled it out for video I don't even have that clamped right there MC k NL so these are excellent for facing if you just want to do some facing and not burn up your good corners here you can put this tool in find some of your carbide inserts it's already got the edges burned up and use this all day for all your facing these are also these other these other tools right here because they have like a lead-in angle to them they're excellent for interrupted cuts or if your machining something that's been safe flame cut any kind of rough heads like a flame cut or a plasma cut these are the preferred corners that you want to use whenever you're doing turning or facing that's why I would like to have some warm bars that use this corner also every now and then you got a piece of steel that's been flaying cut that you've got to turn the outside or bore the inside and you don't want to tear up your good inserts you can just use up these corners right here alright so one other thing that I wanted to point out while we're on this ejected these tools it applies to any tool and that is the torque that you want to use on these clamping screws so all right here's a good example I grabbed this insert because you see it's chipped right here this corner is broke so this is a great insert to drop on that tool right there and use that corner so whenever you're whenever you put these tools on there this is really all the amount of torque that you need just use the short end of an allen wrench and that's all you need now out of sheer habit most of us do this you know you'll tighten it up quick and then you'll give it a little extra there and on that one there but it's really not needed I'm telling you if you'll get some get yourself in the habit of just giving it a nice firm grip like that that's all you need never go full a ball torque on those screws all right so let's move these back out of the way since we talked about those and we're going to go over this face mill real quick too so this is a 3-inch face mill that was given to me by a viewer I cannot recall the name of the viewer but this is an excellent tool made by the company that sells it's called discotech and you can find them on ebay so if you'll notice these these are the same inserts the CNM G and whenever you use this tool you're using these odd corners over here so this is a great tool to have in your arsenal so that you can again use up all of these other corners on these inserts after your use after you use them for turning and vice versa you know so I was really glad to get that it's a great tool to have around here you can't face up to a square shoulder because of your angle right there but it's great for just milling and hogging down metal it's a great tool for that so there you have it that's why I like a CNM G tool now a couple of things I'll point out here it depends on what size lay that you're running if you guys watch me you know that I've got some pretty heavy-duty lays you know industrial quality lays I don't run any small bench top lays old South Bend lays or belt-driven pipe blaze if you're if you're using machines like that that don't have a lot of horsepower a CNM G or a negative rake answer it may not be the best choice for you you might go with something like a CCM T those are a neutral rake insert usually a little sharper on the cutting edge and you can get a little better performance out of your machine whenever you're doing that so just kind of keep that in mind one other thing that I was going to say too is that this is a it's just a little cheap plastic bin one of the few things that I find useful from Harbor Freight that's where it's come from if you've got a lot of loose inserts this is a great way to organize them these are a lot of loose ones that I had floating around in one of these drawers over here and I bought a few of these and it's the first one that I used just to try to organize your inserts on instead of having a bunch of them in a drawer just another good way to keep your shop organized of course you can go in here and you can label the top of it so you know exactly what you're doing what if you know what the insert is you know the grade and all that kind of stuff so I just was going to throw that out there that's a little tip for you right there so I will put the Nam Malaysia for each of these tools in the video description for you guys that are curious about this and would like to pick one up for yourself off those some Amazon links up there for whatever I can find including the black book I'll put that link in there again and hopefully that helps you out I enjoyed the discussion I always like talking to you about stuff around here that's useful and keep this conversation interesting and until next time we'll see you later I've got a couple clips here that I'm going to share with you that I've filmed this week and this is using the MC k & R - 1 - 4 B insert tool using a CNN G 431 insert right here I'm facing off a three inch nut goes on a hydraulic cylinder it's a little bit too thick so I had to bring it down a little bit to add a little interrupted cut there to begin no dents are so great for that I'm material that proven to be a little bit tough so I was kicking the feed rate up there trying to get that chip to break over I just wasn't having very much luck and just one more of the MC knr just just be facing the piece of heavy wall still tube and it works and just use my iPhone and take this clip you

Channel: Abom79

Views: 176,842

Rating: 4.9437885 out of 5

Keywords: abom79, kennametal, mcknr-124B, mchnn-164C, mclnr-124b, rhobic inserts, CNMG, CNMG inserts, cnmg carbide insert, 80 degree diamond, turning holders, lathe, lathe turning holders, lathe turning tools, turning tools, engine lathe, turning and facing, turning, facing, machinist, machine shop, shop talk, shop talk 15, carbide inserts, the best carbide insert, heavy machining, heavy facing

Id: 6AuwE3L6bEo

Length: 14min 32sec (872 seconds)

Published: Wed Nov 09 2016