Miniature Engine Lathe - #3 (b) - Machining the Mini Chuck Jaws

the next parts that i am going to attack will be the chuck jaws to finish out the four jaw chuck now the material that they give you with the kit is 375 wide which means these jaws will have to be positioned on this bar this way stacked the only thing i don't like about that is this little o61 slot on the side that's about one and a half millimeters right there and just under say point nine millimeters point eighty five millimeters deep the only thing i don't like about that is you're going to have to make a ladder bar out of all of these little slots on both sides in order to accommodate the 485 height and the 375 stock utilization now not a big fan of that i'm going to use another piece of material and i'm going to do these inverted and by inverted i mean this way i'm going to use a slitting saw run the slitting saw down the full length of the part both sides that way i know that they're on the same plane there'll be no guess work slice it go around the back slice it again and i will effectively have this profile the full length of this part at which time you can do whatever you want but i think my course of attack here is to split this in half and then section it off at the 485 height that way i can bump end to end and just do all the pockets all the little steps and stuff while holding two pieces final up section it off into four parts and bring in the height so that's my plan [Applause] i am gonna try to do this slot with a slitting saw with an o 51 slitting saw and i'm going to walk it 10 thousandths of an inch vertical to achieve the 0.61 slot width now if your saw is not ground correctly or it's got some bad teeth on it when you try to do something like this all it's going to do is deflect and frustrate you but it's a carbide saw i'm using and i think i'm going to have some pretty good luck with it a smaller diameter saw the better for something this tight there we go 10 18 in the machine about three inches long first step in the process put the slots all the way down the front and rear sides i'm going to turn the machine on until it scratches the top move the blade down the thickness of the blade and from there you can start with the dimensions that you need to hit i need the top of this blade 70 thou below this surface and i need to slot that 62 wide next step in the process is to square up both ends of the oversized blank cut it into manageable pieces so that you get two jaws out of each piece and then square up the ends of those pieces as i may have said before the ideal piece of material for this would be three sixteenths by half but i have three sixteenths by one so i'm going to work with that do yourself a favor while the piece is big square up the ends this assures you a nice clean cut and a good rigid setup overall length really doesn't matter just make sure it's long enough for four pieces for ease of downstream processes it's a good idea to have a stop in your vise now so the blanks i just saw out of the larger plate register against the stop make both pieces the same size the ideal material here would be 3 16 by half inch that would be absolutely perfect i don't have that so i'm going to have to go back to the bandsaw again and rip these to maintain the accuracy of the part and downstream operations make sure any blank that you're going to prepare that's say one of a set make sure all the blanks are the same length both of my jaw blanks are cut down to just over a half an inch now i'm going to sandwich them up and we're going to cut all four at one time there's two pieces per blank they are back to back at this point and stand them up and just nail the top off until they're the height that you want then we can put the stop back in and work on it from there anytime you can kill two birds with one stone figuratively speaking of course do it you'll notice like i always do in most of the milling that i do the rotation of the cutter is driving the material in into the part not to the outside if you mill across the top of the part with the cutter spinning clockwise it's going to roll the burr over to the outside if you can drive the bird to the inside it'll shear it off makes it a lot easier to deburr it almost non-existent on the back side [Music] foreign leaving them in this setup we're going to set a stop flip the parts over and put a notch across the bottom that will trap the set screw in the jaw body and the set screw will will drive back and forth against the undercut we're going to put in the jaw i know there's been some confusion as to how that works first time i've seen it as well but i'm going to go with the design as it is with minor dimensional tweaks but the basic design will be the same and although yes you could line them up and do them all at the same time i think i'm going to do them one at a time just to be sure one of the benefits of working with a blank of a known length is that you can create a feature from the opposite side of where the part is registered if the parts vary in length then the features will migrate accordingly since we're making a lot of pieces or making four pieces out of two blanks having those two blanks identical size we can trust the features that we put in if we're banking from a stop that's not against the surface that the feature is dimensioned from so if this part were to get shorter this slot that i'm cutting right now would get closer to the end of the part the opposite of the stop that is that's the notch we're looking for and that is the groove that is going to capture the set screw and allow this jaw to move once it's installed this is a 187 wide cutter that's just about five millimeters just a little under five millimeters and we're going about 60 thousandths of an inch deep millimeter and a half deep next feature in line will be the outside steps on the jaws and i'm going to position these so that the jaws are facing each other i'm coming in from the outside of the part with the cutter and if you look closely on the print it calls out for a 250 radius in these cutouts right here so that's what the little dotted line is and technically the cutter will make contact with the jaw and go in farther than the 125 steps called out on the print because that is shown to the high side of the jaw and not the undercut but i'm going when i make contact i will watch the cutter profile as it enters the top of the part as the full moon makes contact with the outside edges of the part which will be the hard line that's where i'll set my zero and start my cuts from i'll try to get a good shot of that for you so you know what's going on but for what this is if you were to just make contact with the edge of the part and come in 125 and 250 respectively it wouldn't change a thing after those bottom scallop gets done this is clear it's for the driver that closes these jaws and then we're just going to cut them off stand them up and put about a billion chamfers on them that's probably going to be the longest part of the whole op all right let's get this thing on a tripod throw some chips i am using one of my infamous bridge setups for this because the stop rod i'm using is thicker than the part and i know i'm going to be relieving off the corners of this block so i need to hit the stop low parallels form a lift for the pressure pad pressure pad actually touches the part and not the vice jaw if i were to try to close the vice on this right now i would squeeze the rod and not the part so this is going to overcome that for me and it's lifted and elevated with the second set of parallels pretty simple this is a half inch cutter let's do the do right at the point where the end mill is going to make contact with the part try to keep an eye on there and hopefully the shadows won't get to you too bad but watch for the half moon shape to consume the upper surface right until it touches the edges now i'm going to do it on this side so you know what i'm talking about i want to create an arc that basically goes from corner to corner without wiping out the corners that will be the step back in the print so it's the corner dimension i want and not the actual cut well i want them both but you can't you know let's see what happens all right there we go put something on there you can see if you need to use a loop or something go ahead and do it the steps that are called out on the print on the jaws have a quarter inch radius that means it's a half inch cutter 12.7 millimeters and i'm going to bring it down i'm going to try to position the cutter such that the diameter of the cutter cuts between the two points on the end of the material so that the resulting sharp corners technically will be at the 125. now that small arc that i just cut right there is only about 5 000 to this part and for all intents and purposes you could just hit the numbers on the print as such you're going to see me make double passes on this because you can see the material is bulldozing in front of the cutter it's starting to raise that's going to give you an additional surface to deburr so go back over top of it and as you make your final pass on each step you will remove that burr and do be careful when you create a corner like that it is razor sharp and will cut you in a heartbeat and you won't get a christmas card either i've been waiting for years and it just never happened so be careful this is a four flute carbide ball nose one eighth diameter 1 16 radius 4 flute cutter and if you do not have a ball end mill 1 8 diameter you can do this with the jaw standing up and use the edge of a 1 8 standard end mill to do the bottom trough i'm doing it's very superficial it's only fifteen thousandths of an inch deep uh 1 64th imperial or about one third of a millimeter or less actually it's about considerably less well let's just call it one third for now and get it done full into the part and this is only clearance for the driver key this particular feature is the feature that allows the miniature chuck key to rotate without the high spots of the hex hitting the underside of the jaw so this is basically clearance the flat on the bottom of this part is not really important for function but it may be for locating the part for future operations so make sure you leave something we're about 15 hours on the bottom of this part make sure you increase the rpm on this cutter because the center of the cutter is not moving nearly as fast as the outer edges of the cutter are very much like if you were on a merry-go-round standing in the center and somebody was on the outside if you were spinning with them you'd be spinning a lot slower if they were running around the outside of the merry-go-round trying to keep up with your same thing fairly conventional setup for the chamfer on all four corners all four vertical corners part is in the vice up against the stop i'm using a 45 degree cutter and whatever kind of stop you use make sure it projects far enough out that when you flip this piece over that the stop doesn't go in the notches and i'm using the other part as the offset in the jaw so i get a nice bite simple setup with any operation there's probably a half a dozen different ways to do this but you have to weigh the setup time versus the actual machining time and sometimes it's just not worth setting up additional stops or registration points or aligning the part it's just easier to put the part in there flip it over and have at it standing vertically we could do both sides in the same setup but then again you'd have to worry about making sure it was sitting in the vise square and that would take time to do this is just quicker to set it up this way and go for it print called out for o62 i went 0.55 after the first side chamfer up your parts should look like this or better we're going to put these across the bandsaw now split them right down the middle here put them back in basically the same setup bring them to length and put the final chamfer on the tall side there's an awful lot of places here that burs can hide and if you have one burr on these things it's not going to go together with your chuck body so look them over real good when you're done this part is getting exceptionally difficult to hold so we're going to stand the tall side up on a parallel and i really did want to side mill it because i like to finish with a side mill much better than a bottom mill like this but i roughed these down to about five thousandths over thinking i was going to lay it flat and just didn't like how much meat there was didn't want to squash it didn't want it to pull out so we're going to go this way and this is also a good format for putting the champers on as well make sure you leave the part sticking up vertically out of the jaws sufficient for your chamfer operation keep your fingers crossed on this one guys once i got these parts bandsawed apart and roughed down to almost net shape i realized that the amount of material left over just wasn't cooperative for side milling so i'm going to stand these up now of course when you have multiple parts like this you can put them all in a row and close the vice and do them all at the same time to do that is a really good idea to put a couple sheets of paper on the movable side jaw to take up any deviations in the thickness of the material or cardboard or something but i got to tell you that with so many hours into these parts right now and i do have quite a few hours into them having one pull out blow up would just be a heartbreaker so i'm going to take the extra time to do them one at a time and that way i can be sure at the end when i'm done i have four good pieces starting over and making one piece from scratch would just not be worth it it would be a really good idea to make sure that the machine is zeroed to the center of the part that way your movements on your y-axis are exactly the same for the chamfer front and rear make sure everything clears before doing anything i've had my y-axis zeroed since the trough cut in the bottom i'm going to run a test cut and see what it looks like front to rear with the same value just the last last operation on these guys i am relatively excited about this can't wait to put this thing together now as i had mentioned the y-axis is zero so the chamfer values that i'm looking for when i move the table should be the same front to rear and sometimes it's a little hard to see around the back so i use a dental mirror to get around behind the back of the part to watch when any burrs go away and that's what i've achieved right there take a look at the dro take a look at your dial and know what your value is hit that value and then pull the part out and give it a good look if there's an adjustment to be made tweak it a little bit that's what i just did there that's why i moved so slow i set the center about a thousandth and a half off quick bench measurement quick visual and once you're pleased return to the setup run all four pieces if the stock is consistent across all four pieces this particular feature should be consistent across all four pieces as well now remember i went a little bit less than the print called for just because now as far as the inner grip chamfers that i'm putting on right now the bigger the chamfer you leave on there now the larger the part minimum will be on this particular chuck if this came to a point you could technically hold a human hair but as that flat is bigger the minimum part that you can hold also gets bigger so dealer's choice you call it now you have to bear with me something this small is going to be very tedious to put together without getting in the way of the camera i can tell you that this video series is going to give me a whole new respect for chris over at clickspring and his video ability first thing i want to do is just stick these jaws in here just to get a look at it make sure all the burrs are off everything fits [Music] man i wish you could see me smiling right now i'm grinning here to hear like a little kid if it doesn't fit don't push it got to be a burr that's what we're shooting for that sure looks cool all right let's see if we can get the screws in it'll be awesome if that happens and the whole secret to getting these screws in is to engage the jaw partially as such get the screw down and in and let it pull the jaw into position that sounds good on paper right let's see what happens get it into the cutout look at that yep loving it all right rather rinse and repeat people three more times don't be getting too excited until money's in the bank right let's see what happens i love it for now i run them flush just for yucks these are 10 32 quarter inch screws they've been cut down from quarter inch long they're 185 long now and that is so that they fit in the groove in the bottom here so with this design i would not suggest putting too much torque on these jaws because if you start to roll these threads over on these little screws because of the way it's designed you might translate the damage to the chuck body so be delicate oh man that is just like butter beautiful oh man that's that's money right there let's get a better camera angle for you functional four jaw chucks i can't believe how small this thing is got to say if the rest of this model makes me as happy as this making this four jaw chuck did i am going to be a very happy person by the time this is over the one thing i will do never locate anything that you want to run concentric on a thread just don't do it because threads are inherently not precision location devices therefore you know squeezing stuff together i will put this back in the machine and i'm going to put a recess on this so it locates on the diameter that i will add to the spindle nose i do not want this chuck to locate on those threads i want to locate on a hard feature and that's exactly what i'm going to do all right there you go miniature four jaw chuck in the flesh hope you enjoyed watching that as much as i enjoyed doing it all right guys that's all i got on this piece thank you very much for watching stay well joe pied advanced innovations in austin texas a closing note on this one for all of you that hung into the very end got a t-shirt order in the works so if you're into any ai swag and you want to take a look at what we got coming up leave it in the comment line and give me some idea how popular they will be four color shirts very nice i like the way they're gonna look all right there you go thanks stay well you

Channel: Joe Pieczynski

Views: 65,060

Rating: 4.9821467 out of 5

Keywords: Joe Pie, JoePieczynski, Advanced Innovations, advanced innovations llc, how to, machine shop, shop tricks, shop hacks, shop techniques, shop tutorials, Pm Research, Miniature engine lathe, mini lathe, 4 jaw chuck, scale models

Id: yD0r-ErbRCw

Length: 37min 18sec (2238 seconds)

Published: Wed Jan 27 2021