How to use Chamfer tools for Increased Accuracy - You Should Watch This One !!!!

hey guys joe pie here at advanced innovations welcome back to the shop you know one thing i enjoy about some of the videos that i produce is when they take on a life of their own and spin off a topic or a debate or discussion or a request for how do you do that in this particular video is a spin off from the bed rails of the el1 lathe project but if you're not doing the el1 that is okay because there's more to it let's just say this little close-up that you're looking at right here is one side of this all right that's what we're looking at right there the details for it that is done with a chamfer tool very much like this that was dancing around on all four surfaces and created the surfaces hopefully true to the print now before you can use a tool like this you have to give this a personality you have to give it some landmarks or know what you have before you can successfully create any features that you're going to like or that may represent what's on the print so before we start giving you all the math and philosophy behind that i'm going to take a couple minutes and i'm going to show you how to validate this particular tool so that you know exactly what you have and you can use it on your manual or you can use it on your cnc let's go over to the manual mill and i'll show you how that's done okay in a perfect world the depth that you would plunge this or make contact with an edge let's let's start by saying we need to know whether or not this is a sharp point that being said if you were to plunge this directly down into a hole and create a chamfer with it if you went 100 deep then the chamfer would be 200 wide if there was any flat on the nose of this if you went 100 deep the chamfer would be more than 200 wide because it would be further into the projected angle let me show you a quick way to validate that i'm going to pop a hole in here then i'm going to swap put this in the tool holder and i will plunge this a specified depth we're going to check that chamfer and that'll tell you exactly what the nose of this tool looks like that is a 1 8 about a 3 millimeter diameter pilot hole and it does not go all the way through so i did not punch that all the way through and the reason is that will just relieve some of the pressure on the tip of the tool and allow the tool to make a better chamfer on that hole i'm going to use a 3 8 dowel pin that's about a 10 millimeter little less than 10 millimeter i'm going to roll it back and forth underneath the cutter until i feel a little bit of resistance i am not going to punch the cutter down onto this because if you do that you can chip the tool so don't do that spindle is down spindle is locked coming up with the table okay now it does not fit i'm going to drop the table now until it does table's going down zero out the knee and come back up ever so slightly just a couple of tenths at a time there you go as soon as you have any resistance whatsoever call that your zero point and zero the table again i'm gonna put the cutter back over the hole now by raising the table the diameter of that pin if this were a dead sharp point the tip of this tool would now be on this surface in a perfect world the tip of that tool is now aligned with the top plane i'm going to re-zero the table for this operation i'm going to put it in back here i'm going to slow it down quite a bit and i'm going to come up with the table because sometimes there's spring in your quill stop and you if you need to know exactly what you have keep everything locked and come up at the table i'm going to raise the table 200. here we go now in a perfect world with the plunge of a 90 degree cutter into a hole like that if you go 200 down you're looking at 400 across how do you tell if it's 400 across here we go 500 diameter ball i'm going to show you the math behind this in a minute but knowing the thickness of the material and this is why i didn't put a hole all the way through it the thickness of the material plus the projected height of the ball or from the top of the ball to the surface will tell you what that diameter is let's move this off center get some numbers with a 500 diameter ball in the hole let's make the whole stack see what you get doing it this way is a lot easier than coming up with gauge blocks and indicators and messing around you get a hard number and you go with it the dimension is 8.94 it's just a little under 23 millimeters 8.94 let's do some math and figure out what the flat on that tool is in a perfect world with a dead sharp tool the 200 depth that we just cut should result in a 400 diameter e to d 400 how do we know this well the center line of that particular tool to the edge of the chamfer at a 45 degree triangle these legs will be the same so 200 deep is 200 from the center line to the point doubled 400 now using a 500 diameter ball that gives me a 250 radius so let's construct another 45 degree triangle with 250 as the sides 250 from the center of the ball this will make sense in a minute 250 from the center of the ball to the tangent point on that cone 250 from the tangent point to the theoretical point gives us this triangle right here got away from it let's put this triangle how about this triangle right there okay the 250 250 so let's see what this is it works out to right here 353 and a half is the length from the center of the ball because that's the center of rotation of the radius of the ball right we'll be tangent the same spot on the other side that leg minus our theoretical plunge depth gives us this little guy right here 153 and a half from the top of the material to the theoretical center of that 500 diameter ball add the radius you get 403 and a half or 4035 for everybody that doesn't like that little half thing this is where you take the thickness of the plate the 496 thickness of the plate it was not 500 so you add these two numbers up and your measurement over the ball should be this 8.995 496 plus 403. 8.995 is the perfect real world ideal scenario dead sharp tool plunged to 200 height over a 500 diameter ball reading right there but this is what we got 8.94 now any difference on a 45 degree cone like this any difference is going to be a one to one so technically if you take this 8.99 and a half and subtract what you got we have a five and a half thousandths flat on the face of that tool what does that mean well let's just say this is five and a half thousands this sheet of paper right there here comes the error boy that was an understatement right all right this piece of paper right here five and a half thousands dead sharp tool now watch how this works if you move over a specific distance let's say this is the center line and this is how the waves were cut so if you were curious about that this is how it was done dead sharp tool you move over half the diameter of the cutter to find the edge that you want to find technically now you point to point contact so you would move another you pick it thirty thousand fifty thousand inch i don't care what it is depends on the size of the cutter and whether or not your feature is going to fit in here so let's say you move over 50. you move over 50 and you move down 50 and now you're talking money because now the edge of that cutter is right on the edge of that part yeah that is a perfect real world dead sharp tool never in a million years gonna happen scenario here's the real world scenario right here of course it's never gonna look that bad it may but watch what happens now you find the center of the part center of the tool everything is aligned you move over the radius of the tool this radius not that radius and watch what happens when you move over the 50 and 50. before the tool ended up on the corner of the part if we move over 50 now and 50 down boom you just wipe the corner off the part because of the tip flat so it's really important to know what the flat on the tip is the compensation would have to be you would have to know what this was and subtract it from the depth that you just want to move on your z-axis now chamfer tools are funny you can leave the chamfer tool just slightly off the part like this and come down with the cutter to create your large chamfer or you can step considerably off the part come down to a known gauge point and move back in that is entirely up to you when you use a chamfered tool like this on a cnc machine you must assign some some diameter to this tool and in your cutter copper in your offsets the machine then thinks that it's a standard profile end mill and you work all your numbers from there with a z move or a next move it's up to you but that's what that's all about that's what gotta know the tip of the tool gotta know that right there all right the ways this is exactly what i did with the ways on that little lathe do not work from surface to surface you can if you want to i wouldn't recommend it nor would i recommend putting a pin in between these two surfaces and checking the height because if the height is wrong how do you know that this is exactly where it needs to be because if you remove material from one side yeah it's going to walk down to that new surface while still registering on the other surface now you have a good height but now your center to center is shot have a big land on one side a small and on the other don't do that you must work with these in pairs this particular side of the bed is the inside where the tail stock and the headstock sit and the outside is where the carriage rides you must treat those with respect or it's not going to go together i knew the radius of the part that i was working with because the center to center is given on the print so i split that in half for the radius at that point each one of the moves positive and negative with the cutter are identical same thing with the outer way you know what the center is because it's on the print that just happens to be right here three twelve and a half to the inside of the early rail five sixty two and a half to the center of the outside rail all of these shifts are exactly the same once you come down with your tool leave the z set make your offset same thing for the other side same thing from this one out now i had somebody ask me i'm new to this i don't know what all this absolute and incremental stuff is can you show me well yeah i can show you let's step over to the monitor here for a second i'll do it right in front of you let's say we're going to jump over to the 312 dimension that i just showed you in that drawing i'm turning this with my left hand standing on one leg there we go three twelve and a half right now i'm on the center of the backside inner rail abs absolute i'm going to hit this incremental button right here and it's going to change over to incremental i'm going to zero this okay at this point i can go minus 100 or 104 and i can go plus 100 or 104. now if i want to go back to the absolute this doesn't matter what that is right now let's go back to the absolute absolute now i can go to the 562 on the outside do the exact same thing back to the incremental zero it so now the incremental zero is 562 away from the absolute i know that may seem confusing but if this is an absolute right here we just moved 562 and now you can go step step without worrying about a multitude of different numbers by using the incremental on the digital you can use the exact same number positive and negative from a given offset a very handy way to use the absolute incremental now that you know what the tip of your tool looks like how does that translate to a real world application what do you do with that value well let's take a look let's say you've got your chamfer tool sitting on the center line of your part registered right against the top surface calibrated everything is great you're going to move over to the edge give it some random offset i'm going to use 50 000 of an inch that's about 1.25 millimeters in order for a 45 degree tool to be functional at that offset you have to move over 50 and down 50. there's the 50 off here's the 50 down if this were a cnc machine right now you would tell the cnc tool table but you're using a 100 diameter cutter because effectively that's what it is 100 000 is right there now you can make your chamfer you can come down with it you can come back in with it it's entirely up to you now that's a dead sharp cutter let's take a look at the one with the flat on it and i think you're going to find this relatively interesting and this bites a lot of people tool is on center the tool is registered against the top of the part i don't care if it's a bridgeport or a cnc mill set up the tool the same way on center register right against the top this is option one because i know somebody's going to make a comment well i should just back it off and lie oh you could but let's go with this registered against the top on center when you move over to the edge the offset is exactly the same because this dimension is not going to change right now if you use your 50 offset and your 50 drop look what happens to the edge of the part the edge of the part goes away you just blew it up that flat on the tip of the tool can cost you in the feature of your part let's just say for instance there is an o 60 diameter nose flat on here that's 30 thousandths projected you must subtract that value from whatever this shift is so if it's 50 thousandths this way the calculated flat has to be subtracted from this for the drop so when you come down now the edge of the tool is exactly the same place as if it were sharp can you see the compensation there the allowance let me put that right under the camera a little clearer okay if i were to go 50 over and 50 down i'm into the part by the amount of material missing from the nose of the tool i have to back that out just pretend that that tip of the tool is still there so with the flat on the tool or whatever flat you have on your part once you know what it is and i just showed you how to find out subtract that value from whatever the depth offset is based on how far the tool is off the edge it's not as confusing as it sounds you got to try it a couple times but i hope this graphic shows you sharp tool is a one-to-one a dull tool or a broken tool or a re-ground tool is a one two one minus x and you need to find out what that x is doing with the ball is very handy all right for all you guys are just gonna have to just beat on me for this sharp tool zero you could back this off right now and use your theoretical point in your tool offset and zero this out right now using the flat value that's missing not the result the flat value now you're there see it okay hope that is clear because it's not clear from where i was in now i'm only kidding i hope that is clear when you start doing this when you start messing with chamfer tools and changing tool offsets in a cnc and i know i'm talking cnc but this is manual too guys this is absolutely applicable to manual you saw me do the rails on that little lathe and this is exactly how it was done i had about a four and a half thousands flat on the tool that i was using and i made my adjustments accordingly and for those of you that say you can't pick up the edge of a part with a 45 degree cutter oh that might be a good little bonus section here so hang on let's cut to the end and do that anyway that's going to come up after the sign off thank you very much for hanging in i hope you absorb this please ask all the questions you need to ask this stuff can be confusing and this equal distance stuff is only good for 45 degrees so if you've got any other chamfer well you have to trigger it out and figure out what you got that's all i got joe pie advanced innovations in austin texas i hope you're well now i've received a few comments about the fact that you cannot set a chamfer tool by eye and i would like to try to put some of that myth to bed i am zoomed in extremely tight on the edge of this part this part is square i'm going to take a sharpie marker and i'm going to blacken the edge the cutter is just about as deep as it can go and by that i mean the top of this part does not exceed the edge of the flute there isn't a whole lot left but it is there i'm going to move the black edge into position and i'm going to fire this up and in a climb cut format or approach i'm going to draw it across the material until i see the silver line appear where the black edge is i'm going to reset the zero on the digital at that point stay a couple of thousands away and i'm going to repeat until i get a smaller and smaller remnant track let's do it so initial contact that is minimal at best i've backed off my digital readout and i'm going to creep up on it until i get a smaller flat than that and ultimately no flat at all okay if you have really good eyes you can see there is a shine starting to set in on that edge i am at three thousandths on my digital let's go to two and see the difference all right you can see the extreme not extreme depth but the depth of the first one versus the depth of the second and to look at that naked eye that is just let's just say the camera is really deceiving because this is incredibly zoomed in right now this is where you would let's say if there's a witness mark right there that means you're making contact so let's put it back to the three on the digital set the digital to zero set your dial to zero and if you wanted to put a nice hundredth out chamfer on that all you need to do right now is move the y axis pull the block towards you and it'll give you the hundred thousandths chamfer you're looking for let's do that all right no need to go forward since this is a 45 degree tool this is officially 100 into the part and 100 down if you wanted to check it put it up against the block drop a pin in there do the math look for the height you got it so if you're curious as to whether or not you can set a chamfer tool within a plus or minus five tolerance on a print all day long all day long let's have a little faith and don't go too deep on the first try work that black edge off even the fingernail is going to make it look like it's okay there you go where's that chamfer bye eye

Channel: Joe Pieczynski

Views: 41,315

Rating: 4.9534483 out of 5

Keywords: Joe Pie, JoePieczynski, Advanced Innovations, advanced innovations llc, how to, machine shop, shop tricks, shop hacks, shop techniques, shop tutorials, shop math, chamfer tools, chamfering parts

Id: h88dytFyqAk

Length: 26min 44sec (1604 seconds)

Published: Fri Apr 30 2021