Stock? Mill? Square!

you've just clicked on a video about turning a sort of square block into a more square block just saying before we take this over to the mill and I'll be squaring this in the middle though what we'll be doing is applicable to any machine really it's more a philosophy than a milling technique let's talk about what square means what is Square and does it also imply being flat the square perhaps mean being perpendicular yes it does it's literally the definition of now this isn't technically square it is sharp though dang it might look pretty close but it's right off my saw now typically you want to do this as fast as possible the least number of steps it's not that big deal for a home gamer but you probably want to get to make in your part instead of setting up your stock in this universe blocks have six sides so six strategically executed cuts should bring this into square now depending just how square you need it sort of depending on your machine and how sloppy you are it might take seven or eight like you do six it looks square you check it on the surface plate you find a face or two that's out of whack and you've got to recut it generally speaking six cuts should do it basically like the five-point column exploding heart technique with another point or a face technically alright my wife just stepped out I grabbed a local pro will get the shot and get this back I'll be like nothing ever happened Oh oh that was not good I'm not even sure where it went did it go buying a lathe I might be able to reach you with a broomstick I'll come back to a shop now this wouldn't be at this old Tony flick if I just cut right to the chase so before we actually do anything to the block let's talk about tramming the mill this is what a head looks like this is what a not head looks like tramming a mill means ensuring that the head or the axis of the spindle is perpendicular to the table and hopefully by extension perpendicular to your vice but that's not always the case and you can bet your bottom dollar we'll get into that in a minute now because it's the axis of the spindle needing to be perpendicular to sort of the plane the top surface of the table that means there's two directions we need to worry about usually that's called tilt left and right as you're looking at the machine and nod sort of forward and back some machines you can adjust both on some you can adjust neither on mine for example I can only adjust the tilt now if you have a fixed head and you can't adjust the tilt or the nod that doesn't necessarily mean that your head is tramped again in my case I can check the tilt and adjust it but I really can't do much about the not on a milling machine that isn't always true and these basics videos are just the hardest ones to do but for our purposes the heads got to be tram to the table and you need a square vise think of it like a table saw if your blades not square where your sled isn't straight you're not going to get a square cut and what we need to do here is make sure the sled is straight and the blade is square so just for kicks let's see what happens if your heads not tram din yeah it's not squared your work now this obviously is exaggerated usually if it's out a tram it's just a couple of thousand if you're lucky this is about 15 degrees and it's just to illustrate the point I think everybody can agree that if I move this in this direction I'm going to end up with that angle on this work piece I'm going to end up cutting a 15 degree chamfer there that's how you would set up such a cut so I'm not going to make that cut I think that's self-evident if I cut it 15 degrees it's not going to be 90 degrees now let's cut the other direction with an out of tram head and see what happens you if your heads not rammed it's going to be a little trickier to make flat and square part now there are a couple of different ways to train your mill I just use an indicator on two parallels I managed to get this within a thou without too much trouble it doesn't always go so smooth I'm training over parallels that are about 14 inches across 13 and a half 14 inches since my part is approximately 2 inches that should turn out to be 7 times less the error that I see on the indicator it's called two tenths now that's the error between the access of my spindle and the top of the table and now we introduce the vise where do I even start with these things anything we introduce between the work and the machine is a potential source of error now we tram the head to the machine but we're not putting the work on the table we're putting it in the vise arguably the two most important features of the vise other than its ability to hold on to a part and not let it go while you're trying to do something is that the bottom be flat and parallel to the machine and at the fixed jaw be square in squaring your stock and pretty much any operation you do on the mill the squareness is dictated by that jaw assuming you're working in a vise the fixed jaw ought to be your best friend now typically a higher quality vise is more reliable you could trust it to be flat and square and repeatable you should always check but that's usually the case that's not to say you can't do good work in a low quality vise it just puts more onus on you the operator to check what you're doing is going the way that you're expected to now since I'm mounting this vise I'm going to go to the trouble to indicate that fixed draw into the x-axis in the machine that means put in parallel with the left-right movement at the table technically to square block up that's not necessary might be weird not to but it's not necessary if this fixed jaw is squared of the table it's going to be square to the table anyway you put this vise now we can start to square this thing up and if you ask me it's about time you'll want to start off with the largest face if you think you know why leave a comment down below since this is a cube it doesn't really matter where I start this happens to have five saw on sides and one mill finish side I'm going to start with this one up against the back dog and really for no particular reason then that face is probably more consistent than any of my saw cuts the vise is supporting the workpiece on three sides the two jaws and the bottom the two jaws however are the only two that exert any force on the block they're the ones squeezing and holding on another thing because we have two non parallel faces up against another two faces these two jaws will be sort of vying for power we said we trust that fixed jaw so we want to take this movable jaw sort of out of the equation in order to do that we introduce something between the movable jaw in the work that is either compliant like this little aluminum welding rod or has a small surface contact a little dowel pen or a ball bearing so that's what the ball bearing would look like it's in there nice and solid it should move under cutting forces anyway since this is soft material I'm just going to use some a little bit of TIG rod to keep from marking up these surfaces doesn't really matter now but as we start machining them I'd rather not have a big dimple push in each side hopefully we're confident now that we're pushing the work up against that square fix since we're being all clinical about this let's have a look at the bottom now I don't know if you'll be able to see this the bottom of this block is in square with the back of the block there's a little bit more of a gap here and it's touching the base of the vise back in this corner the way this is set up with this less than 90 degree angle back towards the fixed jaw with a gap away from that fixed jaw we could cut this if we wanted we could leave your friends behind because your friends don't if the block were the other way and the larger angle was back here you could get into a situation where your camming your block in the vise sort of fighting the back surface the bottom surface and out of squareness of your part to avoid that guesswork you can put the block up on a single parallel generally if you have a non machined surface on the bottom of your vise you'll want to put it up on a parallel now we just tap it down a bit firm up the vise and we can take that first cut speaking of tightening the vise you don't need to go crazy here this isn't an a-bomb torque kind of situation these aren't the lug nuts on your car over tightening could lead to other inaccuracies in particular it could accentuate jaw lift that's the lifting of the movable jaw when you clamp work in it if you haven't seen it check out a video called machine shop physics squeeze it just enough that you know you're holding your parts securely we're not trying to achieve nuclear fusion in the home shop here not yet anyway [Music] give this a quick deeper will be ready to move on a side to now I happen to do this with a face mill you obviously could do this with whatever you wanted an end mill maybe a fly cutter I was able to do this in one pass my block is the same size as that face mill how serendipitous okay so we have one machine side for the purpose of this video I'm going to label them just so we can keep track of them I'll call this side Laverne make sure the vise is clean and we'll put that first machine side up against the fixed jaw give it a little nudge I mean cut the second face I didn't quite get it all so I'm taking a second pass and we'll call this side Shirley so at this point we've made two cuts and it's probably a good idea to make sure Laverne and Shirley are square with each other if not that could result in some zany misadventures so my favorite small square is this dye maker square now I don't want anybody out there accusing me a funny business a dye maker square you can basically tune in and out of square like you could set this to two three four or five degrees off of square you'd want to do these checks on a surface plate but that's nice and solid in there it's good and square no rocking no gaps and no that's not my gag one degree right angle plate now we have to machine sides we can take the parallel out again make sure everything is very very clean doesn't take much to knock you out of square put one machine side down and one machine side up against the fixed jaw still using the little aluminum rod [Applause] so we've got Laverne which was our original reference face Shirley opposite Shirley would be squidgy of course so get s and s Prime and that should be square and these two sides now should be parallel since these are now opposing machine surfaces this is the time when you would have taken this to size so this may have been a skin cut and this is maybe a roughing and a finishing cut to get you you know close to the dimension you need to be let's index it one more side and hit this rough sawn face in these videos you may notice that I usually cut from right to left and there's no camera here I cut in every direction coming from right to left just keeps the chips flying back in away from the camera and that brings Lennie in the spec one wolf all right so we've got the four easy sides machined square all that's left now are the two tougher nuts to crack carmine and Frank and as much as I hate to be the bearer of bad news let me lay the problem on you every cut we've made so far has resulted in a face that was perpendicular to the last one we're perpendicular to the fixed jaw in cutting these last two sides really just one side that v cut is the tricky one once this is done the other one will sort of fall in place once you break Frank the big ragu will fall in line anyway this cut needs to be squared to that back face but it also needs to be squared to a side face we need to create like a a right corner is that even a word what's the 3d equivalent of a right angle with one cut we've got to be perpendicular to two surfaces as I've been trying to drill into you guys any cut that you make with this setup will result in a face perpendicular to that fix job so if we put this block up at 20 degrees face the top off that top will be perpendicular to the back or to whatever faces up against that fix job obviously it wouldn't be perpendicular to this face that's up at 20 degrees so we need another reference to set this face up the usual way to do this would be to use a square set the square up in the bottom of your vise or on a parallel and make sure your blocks lined up you could also use a V block a 1-2-3 block or a picture of you Luis anything that you're confident is square as I'd like this thing to be hecka square I'm going to use a dial indicator I'm going to move the work up and down sweeping that face with the indicator and tapping the block until I get as close to zero run-out as possible no emotion on the indicator will mean that that surface will be Square to the cut I'm about to take and then just like before we'll take a cutter to get it down the size perhaps and then deburr it and now we can bring in the last side we have machines faces everywhere else so we can just put this right in the vise little taps never a bad idea and we can clean up the sixth and last side welcome to my surface plate a place in my shop where dreams come to die before we get into how this turned out let's talk about squareness in parallelism measuring and surface plate work could probably take up an entire video on its own but allow me just a moment to do it a disservice just so we're all talking the same language squareness and parallelism are like kissing cousins it can be simple and complicated all at the same time let's start with this shape here not coincidentally you can tell just by looking at it that it's not square if you know the name of the shape leave a comment down below so let's assume our block looked like this shape if you were to measure with a micrometer or sweep it on the surface plate you'd find that each set of opposite faces is parallel no matter how you turn it you always get the same measurement the moral of the story if something checks out is parallel it doesn't necessarily imply that it's square that was fun now let's do this shape this is similar to the last one except now one of the two angles is square if you were to take a mic or an indicator reading here you'd find that at least one of the two sets of faces is in parallel and it doesn't matter which way you flip it it's still the same shape it's still the same problem in this case two different readings mean that at least one of the angles is out of square so before when our block was measuring parallel that didn't necessarily mean that the block was square but if it doesn't measure parallel it most certainly means that at least one of the corners at least one of the angles is not squared our job is to figure out which one of those or which combination of those situations we've got going on with our block and if we can't we might have to find a new job I've got a half now indicator mounted in a heavy surface gauge and I'm going to be sweeping the block underneath it we'll take a look from the top so you're seeing what I'm seeing make sure to actually hit record on the camera and zero the indicator I just did this and the surfaces within a that is about zero one one half of that let's check another side now right off the bat you can see this side is five thousand the last side it's actually six that higher and within a thousands and tooth out of the last set of faces that's like one in a quarter not quite one and a half quick recap we've got two sets of faces that look promising like we said before they're more or less parallel but we still don't know if they're squared of each other I may get some heat for this but off a milling machine 1000 this side part I don't consider that all too bad could probably do better half without you know if you were very careful on each side maybe didn't do this in a vise or did in a better vise but if you're looking for tenths tenths of a thousandth the milling machine usually is in the place to get that anyway - promising sides at one side that's just completely out of whack now there are two things we still don't know if these sides are square to each other and on this crazy side which one of these two faces is causing the problem right when we took these measurements it's a comparison between this face and this face at any rate we have at least one side to fix how serendipitous for checking the squareness I've moved my indicator over to a surface gauge that has a bumper on it and I've zeroed the indicator using a known square let's start off with the faces that measured parallel so that looks like about a thousand towards the indicator so if we turn this around it better say about a sour 1/2 without leaning the other way we know that had to happen because of the parallel numbers we measured earlier let's try the other direction again about a thousand towards the indicator if I turn this around we should get just the opposite within a half of how error there we go it's a little bit more than at that our deviation was a ow plus or minus half a vowel will affect that squareness measurement for argument's sake let's call those two sets of faces good let's find out which two of these faces was the Patsy the troublemaker so that's within a sow that's half a cow there's 2,000 M let's try the opposing face now and a half so that's zero and it's opposing side is to that this is the face we have the most problems with so I suppose we can wrap this up by having a quick look at how you sort something like this out now I'm just going to take relative measurements here I'm not worried about that six thousand sui saw because really it shouldn't have been a surprise at the surface plate he would have probably been keeping track of your nominal dimensions at the milling machine while you were cutting this thing all right so that's actually a thousand before there really was some sloppy measurement it's actually one let's take it back to the milling machine so there's really no end to the things that could have actually caused this to go so far out of whack I mean we said the mill tram over this distance was only a couple of tenths at worse I mean it all adds up but that's certainly not what caused this big of a deviation there could have been a chip back here this general sloppiness there was a bit of an error I don't remember which side face this was but there was a bit of an error when I indicated in the squareness of the offside I mean it's hard to say maybe one and a half al-sham got stuck back there inadvertently now you could just be more careful in setting this up close your eyes grit your teeth and take another cut off the top hope things go better but usually when you're at this point you don't have that much material left to gamble with the thing to do is set the surface back up with an indicator and what we want to do is use the indicator to recreate the numbers we measured on the surface plate let me set it up and I'll show you what I'm talking about all right so that kind of backfired I don't know if you could read that but my indicator was reading exactly those same numbers so easier at the front and it's telling me 1,000 three and a half that could be tweaked in a bit and about two thousand so that's the lowest corner that's the highest corner that means if I take this cut it's going to clean that side up it's going to take that error up unfortunately that's a result of how I managed to contrive this situation let me take another shot at this with the to legitimate sides if you look closely the error pattern is the same we've got a low side and a high side a low side and a high side that says to me that it's something inherent in the setups either the tram of the machine or maybe it's the Vice I'm sure if we were to measure the top now we'd probably get the same thing let's take a look at how you'd fix this and depending how accurate you want this this really just becomes an exercise in indicating but what I would do is put the high side back by the fixed jaw and shim it this is probably little bit thick it's just the note paper I had around but you want to use like I don't know you shim stock but something softer is better like a cigarette paper depending how much air you're trying to take out clamp that in your vise and run the indicator back and forth until your high side actually shows up high so this side would be a sow because we shim the back we've turned the block a little bit and this side stays low so when you take the cut you'll be cutting more in the back hopefully a Thalmor in the back and next to nothing up at the front in this case you could try to tap it in to pick this half outside up a little higher but I think this is just noise in the setup you're starting to get down to the limits of what a milling machine will be able to do I'm not going to go into that because that's going to make this video an hour long but hopefully you follow that logic we're using a shim to make up for some error in the set up taking the cut and checking again one important thing not to lose sight of however is that this might not be the bad side just like before you'd want to check if it was this face or its opposite face on the bottom in this case that was causing these problematic readings but now that that last face that has been fixed problem child we saw on the surface plate this block should suffice for what I needed to do anyway I know that was a little bit on the long side but hopefully you found that interesting [Music]

Channel: This Old Tony

Views: 1,338,499

Rating: 4.9331107 out of 5

Keywords: milling machine, squaring a block, squaring stock, measuring squareness, measuring parallelism, tramming a mill, surface plate

Id: tW8HNAlUXxU

Length: 25min 16sec (1516 seconds)

Published: Thu Oct 20 2016

Reddit Comments

[u/Iamabioticgod]

that was the longest setup for a joke I've ever seen

[u/electrosaurus]

Regardless of where it's posted and much like Howarth's, I will always have time for Tony's videos. I really dig his ever improving production values and dry wit. Plus he clearly knows his stuff.

[u/Unionlaw]

Fell asleep in less than 2 minutes! I' m squared away!!

[u/Wallymagoo]

Love this guys channel!