Dogmeat Helical Milling

[Music] welcome back tox tools i'm tom so today we're going to use an old ls dividing head like this to make something like this on the manual mill and we're going to use a little bit of old school and a little bit of new school so let's check it out so how do you do that right so how do you generate a helix uh with a manual milling machine right so what you're actually doing is you're combining a rotary motion uh which comes from the indexer with a linear motion that comes from the milling machine so somehow you have to coordinate the linear motion with the rotational motion now in the olden days there used to they used to do that by uh connecting the dividing head uh via a bunch of gear uh gear train basically and they would couple that to the lead screw which provides a linear motion so what we're going to do is we're going to kind of modernize this idea a little bit and make the ratios easy to change and give some folks out there an idea how they can set this up and make things with helixes drill bits cutters helical gears you can do conical tapers there's all kinds of interesting shapes that you can do with this so let me show you a couple of pictures of uh how they used to do it in the olden days and then we're gonna go over to the mill and hook this thing up and uh and make a cut well if you're gonna go old school you gotta have a couple of old books right so we've got this is audell's uh machinist tool makers handy book this is a kind of a this is actually pretty good book it's pretty readily available there was like a lot of copies of this but uh there's some great pictures in here let's just take a quick peek at this i don't want to waste a bunch of time so there's uh there's the gear train i kind of mentioned uh connecting the um dividing head to um the the uh the linear travel of the machine and there's an example of cutting a helical gear kind of a large diameter one they've got the cutter tipped over at the helix angle and then it's cutting a helix now you can do spirals stuff like that there's another one um and you can see the gears here they're uh they're actually milling a worm that's what they're doing there so those so you can thread mill uh with this technique as well so there's that and then let's go this is a cincinnati milling machine company and see that's not the one i want there's their version of it now what they did was they spiffed it up a little bit and made a kind of a covered gear box there and had a hand crank so you could index it and do some stuff there too and you would change these gears to change the relationship uh between the um the rotation and the the linear motion now this has got some great examples in here so there's there's a multiple helical grooves um there is a um a form tool that's or a fluting tool that's uh they're making some gigantic cutter here and they're cutting kind of the back side of the uh of the flute of the cutter there which is pretty cool and then some of you guys okay there's another cutter and there's the gearbox and some of you guys will recognize this one here that's the rotor out of a roots blower there right which is a helical form and they've got some kind of weird form tool in there that's kind of hard to see anyway that's just uh i just wanted to show you some examples of there's a cool one there there's a conical one there too with a a cone with a helix on it okay and there's how you would do that and uh so anyway i just wanted to show you some examples of uh of the kinds of things that uh that you might be able to do so let's go in the mill and put this thing together all right first things first let's uh get the indexer on there so we're just gonna whip this up on there [Applause] so come on of course there we go all right to align this what i'm going to do this the side of this has been milled off here so i'm just going to pick up the slot here and this will get me pretty close okay let's come back a little bit let's tuck that back in and we come over and then we'll put some snug as mcgee on there like so and that's right that doesn't always forget about that one it doesn't it doesn't fit underneath there got the indexer up there now now uh what we have to do is uh um we're gonna have to connect some pulleys and stuff here now i made up all the brackets ahead of time and um this is the timing belt pulley that connects to this so i'm gonna get in a little closer and we can see that process okay so with the the crank handle off you can kind of see what we're working with here so the crank handle uh engages these flats and that was what gives you your uh your drive there um we're going to leave the uh the little butterfly on here and this index plate but here's our timing belt pulley we're going to put on there and this is how we're going to connect up the system and you can see that i've cut a little pocket here and these flats catch the uh the flats of that and leave me a couple of threads here just to kind of hold this thing on so that's my driving kind of keys and then you know this doesn't have to be like uh super califragilistically tight and then i have the the lock in here but now we're now we're connected and i want to start on the zero mark there that's why i'm leaving that pin in there so okay and then the the next phase here is this mounts our and i can't reach it from here we have a servo motor that's going to connect to that and it could be a stepper and that's going to pick up some holes in this plate like so and then we're going to have a belt this belt here that goes between the stepper and the um and the indexer so let's uh so the this motor mount bracket uh mounts through this index plate like so some small some small screws here to catch that one all right mr wizard got it going the wrong way look at that wise guy yeah we had to it has an offset towards the front so all right i'm not going to put all the screws in here on camera i'm just going to put a couple in to get started here so all right and then what we have here is we have uh this is a digital servo motor here so it's got an on-board controller here that can store some programs um and that goes like so actually i'm going to put the other screws in there first and i want to keep the connectors pointed off that way so any metal chips don't go in there all right so let me uh finish this up and we'll get that motor on there so i think we're going to do a a disconnected demo here i think uh um what i'm mounting right now is this is the encoder and this is an important part of this whole deal here and i'm just gonna mount that kind of loosely right now um but this thing is a precision counter basically okay for lack of a better uh uh better description so this is counting and telling this how many turns to turn in relation to the turns here so this in this case the ratio between uh the hand crank and this is 1.75 so um as we this rotates a little slower than this does or this rotates a little slower than that does so um is uh i guess what i'm trying to say so let's make sure you get this going in the right way here i think that's the right way [Music] yeah there we go and we're going to put the we got this chunky monkey ground here it's going to go on here [Applause] so okay all right okay and then i'm gonna hit the power supply up and then uh what we can do is we can rotate this and we can watch this turn here so let me get that set up all right let's put the power supply on just so you can see it moving here put a uh little piece of tape on there [Applause] a little flag and then when i so this is the encoder down here and it's going to be coupled to this to this uh hand wheel here much like the geared system in the pictures that i showed you but in this case there you can see the motor turning in relate in relation to that right let's see here let's uh let me steal a little piece of tape off of that one there let's put that on top then on top yeah like that okay and then we'll put a flag on here so you can kind of see the relationship so there's one turn okay so one turn down here gives us whatever the reciprocal of 1.75 is i can't think of what that is off the top of my head right now um anyway so that's the relationship right there okay so let's get the rest of this hooked up here and uh and then we can actually uh drive the indexer um this is the pulley that uh that goes on the motor here and i had to come up with you know these are the these are some pulleys that we had around and um so what i did in this case here is i made kind of a collet arrangement here that has a taper so board a taper in that matching taper there happens to be seven degrees that fits closely on the shaft goes in and then when we pull it up with this nut and that split you saw that right when i pull it up with this nut it it squeezes into the pulley and compresses that diameter and grabs the shaft nice these motors don't have they don't have any flats on them or anything like that for set screws and this was a kind of a hubless pulley right so i would have had it gone through the teeth to put a set screw in and i kind of despise that screws anyway so um let's see here so i'm gonna get this belt on and uh and then i'm gonna put the the last little bit here so this goes on the uh the hand wheel here or excuse me the uh the longitudinal feed and connects to the encoder via a small belt too so let's uh let me get that on and then we'll come back okay so we're all connected here um let's see make sure this shot pins out of here so now we are coupled from the x-axis linear travel to the rotational axis of this dividing head and i'm just going to go ahead and rotate it for you there so you can see it okay you see the head is turning and i back up and it kind of reverses the uh that whole thing okay so and um like i said the the ratio between these is 1.75 and uh this being the slower the slower side uh this ratio here is 40 to one so now what it's set up for it is currently set up for a particular helix which is a one in 14. and what i mean by that is one turn in 14 inches of travel okay so 14 inches of travel uh on this lead screw is 70 turns so it's 40 over 70 or 70 over 40. um that's that's the ratio which is 1.75 um the uh what do i want to say so as i turn this um 70 turns right i get a one full rotation of the uh 40 to one indexing head hope that makes sense so let me put some material in here let me get centered up and uh we'll do a little cut and you guys can watch it's pretty fun all right i think we're ready here i got a this is a piece of plastic here i grabbed uh it's pvc pipe uh and i have a 1 8 cutter here and um what we're gonna do you know i'm just gonna eyeball a little cut in there like so actually zero this quill and um so we're all coupled up let's see i think we're ready here let's uh zero that i'm on center line here so let's just uh kind of get a try going here so you can see the the behavior so we want to take all the slack out in this direction okay and i'm just gonna hand crank it initially yeah okay all right and there it goes so that's a one in 14 helix uh let me let me come up and uh make one pass let's come up to some even number here um i think i'm gonna come up to four four inches even right there now i'm gonna lift out because i don't want to uh um have any backlash issues you know to make it's partially mechanical so now i can come up to my starting point again okay and then i'm going to come a little deeper in this case let's go uh i don't know 30 foul deeper and there we go and so what we'll do is we'll cut a series of grooves around this uh and i'll describe how i'm indexing it for the next group which uh pay attention there mr bozo to visit us here okay there's four inches i'll come up come back all right so there's our starting spot again and let me just double check yep our shot pin goes in so this is a 24 index direct index uh wheel here so this has holes in it going in this direction that this pin picks up right so as long as in this case that's what every 15 degrees or something right and so we can do 15 grooves if we wanted to um i'm not going to do 15 grooves in this case we're just going to let's do uh let's do six okay we'll do six grooves in this and uh so the way i'm going to advance to the next groove is i'm going to disconnect the encoder from the hand wheel i'm going to leave the table where it is and i'm just going to rotate the motor until i drop into the into the 1 6 index hole and then i'm going to reconnect the encoder so that's a reasonably accurate index you know um now if you got clever you could set this up and uh have it index uh the correct number of turns um you know for different divisions and whatnot uh this thing's this motor setup is smart enough to do that um with you know maybe you need a little arduino or something like that to do that so uh so let me uh well let's see i'm i'm there so why am i yeah i'm there let's just disconnect this i'm going to lock the table so it doesn't move on me and then i'm going to loosen this and you're going to watch it rotate okay take me a minute not like i got a uh a nice hand wheel on this thing all right so there's my there's my first mark there coming up right okay oh and there it goes okay so i'm in so now i'm gonna i'm going to re-lock the uh the retaining screws and take that out and now i've indexed 1 6 of a turn and we'll go ahead and start our uh oh crap i forgot how far down i went i think it was 30 yeah okay let's do that okay and uh i'm just gonna take the whole thing in one wack there now and there we go you know and i can power feed this too it doesn't care i'm just turning it by hand because um i can't okay there's four inches all right we'll come back go past come back to our starting position which is on the dro here right there okay and then i'll index it another sixth all right come to the starting point again like so okay yeah mark that hole there so it's not every hole is marked all right so i'm gonna go ahead and uh uh yep it goes in i'm gonna index to the next one two three and there's my fourth hole it's kind of interesting you can uh let me pull that out let's go back there it goes okay this is a 2 000 count uh per revolution uh encoder right so it's got a lot of resolution so you can really uh get this to the sweet spot pretty easily uh in the shop pin there so uh did i screw that up i don't think i did yet i don't think i did screw it up yet why am i off that says six eh whatever i'm not gonna worry about it for this demo here um let's take another cut [Applause] all right there we go so full disclosure i bozod one of the indexes and uh so i cut another one um so that uh i could have the i could have the money shot here so anyway i uh uh anyway i don't know what i did i was talking and not paying attention i didn't index it correctly but there's the kind of stuff that you can do now um there'll be some improvements to this uh with a uh a little box so that there'll be some adjustments so that you can change uh the relationship the ratio between the motor and the um [Music] and the lead screw you know the table movement so you can change it from basically whatever you want so this happens to be a 1 in 14 and we didn't do a full turn clearly because this isn't 14 inches long but that'll be the next improvement on this thing so anyway i just want to show you guys uh this little thing that we've been playing around with me and my friend mr bill he's responsible for the electronics part and i'm responsible for the mechanical part and and suggesting the idea i guess as yeah the other part that i had to add it to the the mix there so i hope you enjoyed it and um uh gets the creative juices flowing out there with all the little electronic guys out there thinking about this so talk to you soon [Music] you

Channel: oxtoolco

Views: 85,304

Rating: 4.9606743 out of 5

Keywords: Machine work, Toolmaking, Mechanical design, Dividing head, helical milling, Helix, How to make gears, How to cut a worm, Indexing, Milling machine indexing, how to sharpen a drill

Id: AVydTvwqmRs

Length: 25min 33sec (1533 seconds)

Published: Mon Jan 18 2021