A Brief Chat about Carbide Tooling

[Music] so last time we had us a nice little chat about high-speed steel and how awesome of an option it is especially for us home shop crowd I mentioned that I'd slowly slipped into the seedy underworld of insert tooling but still like to keep plenty of high speed steel on hand it's kind of like my recommendation for the convenience store right down the street I wholly endorse walking there it's the healthy green option but when I need to go I usually Drive all right I'm ready push anyway in order to round out the big picture I wanted to talk about carbide I'll start off briefly with braised carbide but mostly share what I know about insert tooling not that I know a ton but the little I wish someone would have shared with me when I was getting started but we'll be looking mainly at insert tooling in this case for the leaf but by and large this also goes for the mill if you stick around we'll talk about choosing tooling for your shop what to look for the most fun shapes and colors to get what they do were to get them how they taste and most likely plenty of completely unrelated stuff to get us back on track we're talking about tooling for our machines that we need to cut raw materials into scrap metal into parts for our projects we said a tool is any material harder than the material we'd like to cut that's the right shape to do so efficiently the last video was all about the aspects of what quote unquote right shape actually meant and high speed steel is harder than just about any material we as hobbyists are likely to run into combined with the fact that it's cheap it makes it an ideal cutting tool in fact in some cases it's preferred over the car by tooling we'll look at in a minute but we had to cut the high speed seal to shape and to do that we needed something harder in our case it was a grinding wheel in fact cut high speed steel into shorter pieces like the slotting tools I use in my shaper you'd be likely to use an angle grinder with a cut-off wheel moving our way up the food chain and hardness brings us to carbide as you saw in the beginning of this video carbide is harder than high speed steel and therefore properly shaped can be used as a cutting tool now this is just a carbide blank you can buy them just the way you buy high speed steel blanks but usually you'd find carbides already in the form of a cutter here I've got some lathe inserts and a couple of small end mills and that right there is probably the reason insert tooling draws such big crowds they provided already cut the shape high speed steel is more than enough for what we need to do in the home shop but it's on us to shape it and for someone just coming out of the gate I appreciate the appeal of a cutter that's all ready to shape and ready to go but oh how many shapes there are okay old Tony carbide is harder and comes in funny shapes who cares I'll tell you who cares because it's so hard it has the potential to move massive amounts of material very quickly though technically I think it might be more the temperature and wear resistance than the hardness depending on the material you're up against but what carbide can do in five minutes might take high speed steel half an hour for some people EPG period manufacturers how fast he can get her done is the name of the game I know I know weird name for a game unfortunately carbide just on its own isn't magic you need a machine with enough speed and horsepower to actually move the amount of material carbide is capable of moving that takes us to point number one and I'll be honest with you I don't know how many points is carbide wants to go fast and that only gets worse the smaller your work is if you're making screws four at a no-risk watch the carbide might want to see ten thousand rpms but for now let's not have the details slowed us down point number two carbide is brittle it's hard but it's not tough in the technical sense of that word now granted my info is a little bit dated good car buy these days isn't as brittle as it used to be but from our perspective especially compared to high speed steel like in our latest tools drill bits and mills etc its brittle the carbide we use is a matrix it's a mixture usually tungsten and carbide powders pressed into a shape in a shape conducive to cutting metals but they also press this stuff into other funny shapes like armor-piercing rounds but I'm getting off topic point number three because it's a pressed matrix of various stuff except for some special cases carbide isn't as sharp as high speed steel especially when you start adding things like coatings being aware of those two things that it's brittle and potentially not a sharp will go a long way to making your time with carbide much better than it did on your first date and really will be the undercurrent of the rest of this video so enough of the technical mumbo-jumbo let's get down to brass tacks wait not brass tacks that's a different video let's get down to a brazed carbide you're looking at brace carbide lathe tools you can also get brazed carbide mill tooling like face mills and stuff like that they're called brazed carbide for a hopefully very apparent reason it's a piece of carbide raised to a steel shank since the tip is the only thing doing the cutting it's much cheaper than a solid piece of carbide solid carbide tool holders exist but they're another can of worms entirely so braze carbide isn't exactly the next step up between ispeed steel and insert tooling practically speaking if you're new to this skip raised tooling altogether I think that's a fair blanket statement to make when I started out I bought a lot of this stuff especially the threading tools it's magical carbide and cheaper and less of a commitment then insert tooling but fact of the matter I'd break it faster than I could buy it though with time and experience I've come full circle and now in some cases love using this stuff but to get there you have to play by its rules in fact I now often braze my own I just take a piece of carbide and glue it to the end of a convenient support this is a little undercut tool that I used in the coffee pot video you can go back and see this thing being built in this particular case I think it was just one of these inserts I don't have a holder for and I didn't even really need the properties of carbide but it just made a convenient tool I just needed to reach in there and do a little undercut in aluminum if I couldn't do this my option would have been to grind a heck of a lot of high speed steel off of here to create this undercut but brazed carbide finds a lot of uses down here in my garage here I use to create scrapers and again it's either just raw carbide blank or some old insert I don't have a holder for but if you buy the cheap raised carbide you know that comes in those little kits of three or five in the fancy Lowe plastic box usually slathered in gold paint you'll run into the same situation that I described back in the boring head video this is a brazed carbide boring bar and apart from the potential quality or lack thereof of the carbide they're really just giving you a slug of carbide braze to the end of the steel shank it's up to you to check if the clearance and rake angles and sharpness and nose radii and all that kind of stuff is up to snuff and with carbide that's not necessarily as easy as high-speed steel you're going to start to need special grinding wheels the green silicon carbide and then diamond honing tools to really finish that edge once you get there and you're comfortable with that these things are spectacular you can hone these to a sharper edge then you can insert tooling not because there's anything special about it just the geometry is more conducive to that yet big flat surfaces that are easy to hone instead of complicated little inserts with funny geometry and chip breakers and all that kind of stuff though you certainly could own and resharpen your insert tooling if you really wanted to just like Stefan carbide just wants to be treated right if you try to make any fast moves it'll get into a tizzy sorry not a tizzy stephane carbide just up and breaks no way around it you bump it drop it stop it while it's in the work and it's splitsville like we mentioned it's brittle and sharpening ain't so easy as high-speed steel well technically it'll sharpen in the same way but it requires more stuff to do and takes longer because it's so hard these tools want a nice steady chip load even if it is heavy and no fast moves they also don't enjoy intermittent cooling so either use them dry or you flood them the thermal shock can crack these things to some extent that's gotten better over the years but generally either cut dry or flood them they also don't like being in strong light and you shouldn't feed them after midnight but after all that if you do want to buy this stuff I mean after all it is cheaper than buying into insert tooling get the good quality ones they won't be as cheap as imports but you're much likely to have a lot better experience with them not to mention the good ones are usually ground and ready to go and when it does come time to sharpen them it's exactly the same geometry as we talked about in the high speed steel video all the same rules apply clearance angles relief nose radii grind them to suit the job you want them to do and just a quick thought this here is my ball turner you may have seen this in the vice handle video it uses a carbide cool bit in this case it's an old broken end mill I like to make them myself now although this thing is dull and has giant chips missing out of it it's still a good source of carbide so broken carbide end mills are a good source potentially for tooling hopefully you can see the end of that it's just like the grind we put in the high-speed see on the last video it's got some relief on the front a little bit of back rake and some radius corners now you could use these for example as inserts in homemade boring bars or I guess fly cutters you could make Reimers countersinks you know sky's the limit to make these more manageable you'll likely want to cut them so you just have the shank it gets a little bit tricky but if you Nick them a bit with a diamond wheel like those little one-inch or one and a half inch diamond wheels for rotary tools like a dremel tool just knick it put it in the vise give it a sharp back with a hammer and it'll break they said this stuff is very brittle [Music] which finally takes us to the main subject of this video insert tooling about time to now I thought about this for a minute but don't think there's a real clear linear way to present this so I'm just going to jump right in there are though a few important things to keep in mind when getting into insert tooling first any one of them would work sure there are a million different styles shapes colors and flavors but new they all cut the real question is usually which insert is best suited to what you'd like to do and the equipment you have this is the part we'll probably talk about most seconds the fundamental physics are identical to what we talked about in high speed steel video clearance and rake etc they're exactly the same except someone else made them for you you just want to be sure to pick the one that you need and finally probably the hardest one try to get the good ones I know they're expensive but in the long run you'll save time frustration and probably money trust me I threw more money away it's a cheap import junk then I care to think about probably the single most popular question people have is where I get my nails done a close second however is which inserts I use and which I'd recommend now I think I've mentioned this before but almost all of my inserts willing for the lathe is scavenged I mean either I got it with the lathe founded at flea markets Craigslist kind of stuff and what I have to be honest is actually a bit big for my lead but these are the sizes I run into most and therefore tend to be the cheapest so frankly that's what I use they're not optimal for my use but they work and the price is right for me so in no particular order let's jump in first you'd want to get something that's suited to the size of your lace these two holders and insert styles are exactly the same but they're two different sizes these happen to be W nmg inserts but we'll get to that in a minute on the right the one in gold is the one I use probably 90% of the time of the inserts that I find most I like the wnm G's again they're probably not the best match for what I do but of the ones I find these are the ones I like this on the right was given to me Bryan Barker of newfangled solutions of the Mach 3 and Mach 4 fame got ahold of me not long ago told me he enjoyed what I was producing and wanted to send me a few things and he was kind enough to send an industrial license for mock for a pendant and the tool holder you see there on the right he sent me that to a holder along with two style inserts that fit that holder well get a closer look at that shortly for anyone who's interested I do have plans to do a part three of the CNC basics video and I've slowly been migrating to Mach 4 so we'll have a closer look at that there I guess he must have noticed that I used this style of insert a lot and that's why he sent me this style get an axe word specifically though he did ask what size shank I preferred you can see my tooling tend to be big because again that's what I find but that leads to some other I don't want to call them problems but considerations on the late I need a larger tool post to accommodate the larger tooling that gets a little bit more overhang makes my setup sometimes a little less rigid ideally my lady would use about this size tooling but the first thing you'll likely notice is they come in a ton of shapes in fact shape happens to be the first letter in the insert designation so we'll walk through the standard designation one code at a time and when we're through well that should do it I will make some recommendations at the end and before we get into shapes one last thought on folders unless you only use your tooling once a year and do very light cuts maybe on small parts it pays to get a good quality holder the holders are expensive cheap holders are just that we keep going we're out and won't hold the insert firmly unless your screw strips right out which they usually do you might not guess that the holder is causing your problems ah doodles I can't believe you folks let me go on and on like that was broken insert in the shot I'm so embarrassed I guess that's what I get for manhandling the tooling on the table the way I've been doing it hey Bry if you're out there my apologies I mean that was the first cutting edge I tried and I'll be honest this past week I've been putting this insert through heck and back just seeing what he could do and that edge I mean it was holding up like a champ I couldn't throw a material at this thing fast enough then I done gone and chipped it here on the bench so earlier I mentioned insert designation insert designations are basically the standard naming convention for machining inserts in this case we'll be looking at lathe inserts and in my case the W nmg I mentioned the first letter specifies the shape the W in this example refers to what's called a Trigon shape the second letter is the clearance angle the N here is zero degrees and means that this insert has zero or no clearance now keep in mind this is not the rake angle this is the side release zero degrees the side is square with the top the third letter is the tolerance it basically means that the insert is made to within two to five thousandths of Industry specifications the fourth and final letter is the hole and kick raker style G means the insert has a cylindrical hole and that there's a chip breaker on each side after that four letter designation there are usually three sets of two numbers this particular insert is an OE o 408 the first pair numbers refers to the size of the insert or the inscribed circle o eight in this case is eight millimeters the next pair of numbers is the thickness oh four again in this case is four millimeters thick insert and the last pair of numbers call out the nose radius again here o eight means 0.8 millimeters like I said this code is standard for lathe tools milling is a little bit different but check online for the decoder ring and it's usually pretty easy to work out I most often look this stuff up on carbide to depot.com but you'll find that each supplier and manufacturer will have a similar document that breaks down the code names for you let's have a quick simplified look at what shape means like what the implications are of the different shapes we'll look at five styles for now round square trigon triangular and 55 degree diamond the round one here might not actually be a turning insert but it's the only roundish one I have to show you these are sometimes called button inserts round is the strongest shape insert and leave some of the best finishes around however you can't turn sharp inside corners with them they are popular on CNC lathes though for turning funny shaped contours next strongest is square but because they're square they don't have clearance leave good sharp inside corners they'd likely chatter and are usually used at 45 degrees for turning facing and chamfering all-in-one tool next in my lineup is the Trigon it has an 80 degree included angle that gives it five degrees per side in a shoulder and can do both turning and facing Trigon however I believe always have negative rate next are the popular triangles they work just like the Trigon though a little weaker but instead they do come in positive rate and in that variant they only have three cutting tips we'll cover that next and finally here I have a 55 degree diamond these give you access into finer features I'm really getting to like these but with positive rake they only have two cutting tips now there are a lot more than these five I'm showing you but hopefully you're starting to get the picture that brings us to the tool holder itself holder and insert are intimately related let's compare the wmg set up on the left with the dcmp on the right according to the second letter in there insert designations the wmg has no clearance and the dcmp has seven degrees again the N was zero degrees and the C and the D CMT tells us that it's seven as we saw on the high speed steel video you need clearance for a tool to cut properly and here's where the holder comes in the W nmg holder on the left in this case has a built in five degree negative Ridge it's sort of by nature holds the insert sort of a five degree downward angle this gives the W n mg five degree of clearance sort of on the front and the sides and also changes its effective rake angle on the top the rake being that five degrees plus or minus or whatever the manufacturer actually built into the top of the insert itself the dcmp on the right however has a flat seat in the holder it's adding nothing to the insert geometry so all the clearance and rate is built into the insert itself if you want to build your own insert holders these are the type of inserts to look for so again the insert and the holder work together to create the final cut in geometry now that geometry leads to some interesting implications because the dcmp has sort of built-in clearance and in this case happens to be a positive rake insert we can get to cutting edges out of the answer if you flip it around that seven degrees is now going the wrong way for this insert to work the W N and G on the other hand because it has no side clearance it's completely square now because of the shape it's given us three cutting edges to begin with three cutting tips as opposed to two for the diamond but like we said this has the advantage of being able to get into some tighter spaces but this tool now can be made symmetric so if you flip it there are another three cutting edges so the short story is this has to cutting tips and this has six let's throw a couple more in here for discussion sake this I think is a milling insert on the left this has some very high positive rate so you can see flipping it over wouldn't do much good in terms of getting more cutting edges but because it's square it's got four the dcmp because of its shape only has two but you can't really compare the two they're for two different jobs this I believe is a CCM tea it's also a diamond shape but has a larger included angle because of the high positive rake on this it also only provides two cutting edges the back is flat and finally there's a triangular insert these go on my boring bars the boring bar that I use this in has a negative rate the effective rake of the entire tool is negative and so this gives me twice the cutting edges just like the negative WN mg1 insert in either of these files gets me six cutting tips the same price of the insert and since we've gone all up close and personal with these inserts while we're here have a look at all the different chip breaker geometries the different styles each manufacturer has more or less their own flavor of them and they're built to work with specific materials at specific speed and feed rates usually if you're trying to buy this stuff from a rep you might not be spitting up clearance and relief angles that you want and to holder Styles you'd probably tell them you know what the job looks like that you wanted to do what the material is and what machine you have at which point the rep would likely pull out you know they're cutting tool from the future with lasers and sharp teeth and leave it with you and send the invoice to somebody else so let's give one of these a try since I mostly use WN MGS and this tool that Brian sent being the only one with pedigree papers we'll try this one out on the lathe I'd also like to give it some airtime to thank him for sending it to be honest now it's not my intention to plug this tool per se as it might not be the right tool for you but for the beginner the way I see it you have two options if you're trying to save money let's be honest you'll probably check like eBay or Craigslist and do all of your own homework if you have a small lead the usual recommendation I believe is like a CCM T or a TC MT choose one for the material you use most but have a look online maybe someone has already done some experimenting and can tell you what they think works best for your particular machine option two the low hassle approach is to call a reseller or manufacturer now being a hobbyist and only wanting to buy one tool doesn't really work to your advantage here but if you want to talk to Brian it's my understanding that they're targeting the Hobby crowd they only want to tell you one or two inserts now this particular cool this is a kenda metal in this specific size costs about $90 that's just the tool holder the inserts if I'm not mistaken at the time of this video or about seventeen dollars each now they do have six cutting tips so in my case that comes out to I don't know two or three dollars per tip now Brian told me that this tip will last me forever so joke's on you Brian I plan to use this forever if you get this through them I think I'll put a link up on the screen I think it's maniacs tool crib included in that price is sort of some technical support for the tool a little bit of hand-holding on their part so if you call them up tell them what machine and material you're trying to cut they'll help you pick a tool send you the tool I believe they include a spec sheet for the inserts so you'll already know the feeds and speeds and you know all the parameters the tool is designed to run it so Brian sent me two inserts for the same tool holder the one on the left here is a little bit sharper but I think it wants a minimum depth of cut is like I don't know eight to ten thousand Val whereas the one on the right according to the spec sheet won't start to break chips till about thirty thousand to cut so if you needed to take off just one or two or three foul you know depending on your machine more than likely in that case you'd switch to a very very sharp high speed steel sort of home ground tool so as I mentioned I've been playing around with the coarser of the two inserts in some chromoly I think it's chroma 4150 I think this is the same stuff it was doing a spectacular job I don't know if you guys saw any my other videos with this chromoly but my other insert got a lot of birds nesting and this is breaking off a nice you know not discrete chips but these little noodles I was able to push it up to about a fifty thousand to cut before my lathe started choking out in this mint here although wasn't actually chip breaking till about 3540 South at least with the feed rate I was using I don't know if you to those depth of cuts what I'd actually like to do is try the finer insert the one with the ff2 chip breaker I think and just see what kind of surface finishes and chips I can get with the carbide again if you go back and you look at the taper tooling video the surface finish is good but it's not like you know spectacular again the inserts that I use I'm not mistaken they might be Mitsubishi and for all I know like I said I scavenge them they might be for cast iron but they move material so keeps me happy so let me load this up and we'll see what that finer insert does so I'm going to run in the way that 1200 rpm and that's the max this machine will do I'm only going to take in 10 or 15 thousands of cuts with this insert and I'm going to be running at the slowest feed rate I have which on this machine I believe is about seven or eight seven see how it does I'm starting out with a tenth out that's the cut I just more really want to clean this up just so subsequent passes are actually taking on a consistent chip load I'll do 10 15 maybe we'll push it to 20 see what happens so and if you can see that but to spectacular finish I can sort of see a rainbow of colors in that it wasn't breaking chips though let's try 15 this will be 20 once I actually dial it in it'll be twenty let's go to 30 so 30 actually was breaking chips I picked up a little cluster that ruined my surface finish I'm gonna try 35 keeps picking up the initial chip but it's chip breaking spectacularly let me try that 35 again man this chromoly stinks I'm going to up my feed rate but drop this back down to 15 so I'm really happy with how that turned out I don't have space here to show you the chips the chips are beautiful surface finish is perfect the work actually seems a little bit cooler than my old inserts but that's maybe a depth of cut thing at any rate I think that's about all I had to say for carbide inserts for now anyway here's hoping you found that useful and until next time thanks for watching carbide

Channel: This Old Tony

Views: 1,492,395

Rating: 4.9184937 out of 5

Keywords: insert tooling, carbide lathe tooling, brazed carbide, homeshop machining, cutting tools for the lathe, insert designation, insert nomenclature, insert specifications, understanding inserts, how to choose an insert

Id: rsFFWYo8ugw

Length: 28min 8sec (1688 seconds)

Published: Fri Jan 20 2017

Reddit Comments

[u/NorthStarZero]

I think I might do a short video on aluminum-specific indexed tooling....

[u/DainBramage23]

I bought a wnmd tool about 6 months ago and a dcmt about two months ago. Definitely don't regret it. Grinding hss and those HF brazed tools gets really fucking old after a while.