Acme Thread Lead Screw for Tailstock

[Music] we're gonna begin the next component for the tailstock parts that I'm making and this is going to be the piece that I'm machining right here this is our piece of material this is some one and three sixteenths 1144 stress proof to this material right here that we're gonna use is some good stuff to be able to make that out of got some good strength to it and it's free machining as well so real easy to cut and this is the this is the nut that we just made in the previous video this will be the nut that screws on to that that lead screw right there like so all right we'll be single-point threading this this side well both sides there we've got a 3/4 16th red on this side that'll be just for a standard nut to hold the hand wheel on this side here and then this side we will do our six pitch Acme and I've got a tool bit right here and got out of granddad's tool box piece of Rex 95 and it's already been ground up I'll have to touch this up and it's already been ground up for a 6 pitch Acme thread and this is just a standard Acme thread pitch gauge right there and just verifying that that one's ground up for a 6 so we'll touch this up make sure we got good good sharp cutting edges right there before we do our threading but that's what we'll use so let's go down to the victor lathe and go ahead and get started on first thing I'm going to do is go ahead and get the in get the ends faced and get it face to the proper length just use my 12-inch calipers and we'll get a rough measurement on it right here looks like we've got approximately 75,000 it's maybe 80,000 to come out so I'll just go ahead and put it back in here and you know we'll just take a cut on that I'll pull it back out measure it and then we'll take the final cut that in length isn't isn't super critical now we got both ends face square I'll just do a final measurement on this yeah looks like we got 50 I'd say about 50 to 50 mm to come off the total face they're looking for seven and seven eighths on my total length plus or minus a few foul so I took 50 thousandths we got eight seven point eight seven seven we're good we're going to start with the the shorter end that takes the three quarters 16 threads and shouldn't really need a center for this in right there typical stick out is going to be two and a half times your diameter that's just a rule of thumb that's not for every circumstance so I'm just going to go ahead and stick it out two and a half inches because we want to turn it back a total of about two inches really so we'll just start right there and we should be able to do our turning and threading right there it's gonna be our finish pass there to bring it to 3/4 [Applause] clean up the face five thousands also we're also going to turn this down right here to inch and 1/8 all we got to do is take sixteenth off that it's going to turn it back song alright so we've got this area here turned down five thousandth and we've got a 1/8 wide a radius undercut there this is a thread relief there and we've also got our chamfers so we're ready to touch off and go ahead and cut our 16 pitch thread do it an n feed with the compound we're gonna get a touch off here there's our touch off I'm gonna zero out of the compound a PETA in mm and it will make the scratch pass here we've got Mike on my cross slide set to zero all right and we'll check it and it looks good that's our 16 pitch you guys remember how to calculate your estimated compound in feed take 3/4 divide it by your thread pitch and that's going to give you your in feed for your compound so we're going to be moving in approximately 46 thousands start with a 20,000 cut here now I'll probably get a bunch of people asking about or I'll leave their live leave comments anyway why no Lube why no oil why no lubricant you don't necessarily need it on this on this stress proof it's a pre-cutting material and you're using that carbide you don't really need it for the little amount of cutting that we're doing right there I'm going off of a class-3 fit for a three-quarter 16 that puts us on a maximum pitch diameter of 709 thousandths range to 706 to 709 so I'm just using my pitch diameter mic right there looks like we're at seven thirteen and a half all right so we still got four four thousands to go and also have this go gauge there and it also lists your go and your your pitch diameter there as well [Music] just getting down to a few little white passes here let's go ahead and check our threat [ __ ] looks like I landed on 708 all right so we're right there and are right there in our range of where we wanted to be I need to take a file take a file and file the high spots off the threads break the sharp sharp thread right at the very end where it comes into the relief and then the the very start thread right there it's good blow the chips off try our go gage looks like it's fitting just like it's supposed to all right well I'll hit this in with a little bit of scotch-brite just to kind of brighten it up and then we'll flip it around start on the other side all right we're gonna put it back in the sixth jaw here give myself a little bit of room I don't want to go all the way up to the shoulder because that that shoulder there is only eighth wide that's gonna be real close so this chuckhole is really well so I'm actually gonna pull this out just a little bit this is gonna give me some room here to work that's why and it should not push back we'll just snug it up good and this shouldn't run nice and true too got this Chuck dialed in whenever I was dialed in before it was repeating a half a thousand every time with a gage pin anyway that's running nice and straight so now we'll drill a sinner hole there and then do our turnin this is going to be 3/4 of an inch from end to end there and we're getting down to our final two cuts here we're going to make two finishing cuts and looks like we've got forty four thousands to come off of it we've got our shaft turned to size this is where our undercuts going to be you may not be able to see it very well but there's a little tiny shoulder right there because this area right here is three quarters of an inch and if from here on out it's going to be the five towel under so we're going to use this same radius tool I used before which is a parting blade with a radius cut on the end and we're gonna cut our thread relief because this is where our tool bit will start making our thread cuts right there just getting out of touch doll for a zero I try a little bit of oil on this one here and see how it does and we're starting to get a little chatter so I like to slow her down I'll move the tool bit over death right there go ahead move over actually let's go we're gonna go this way right there [Music] we can have all the thread relief we want in this area here so I'm gonna go ahead and widen it out so that we got plenty of room for our tool bit to go in there all I did was just touch the top of that tool bit right there to kind of clean that up and I think the sides all they need is just a nice honing they don't look burnt rolled over I think we'll just do some honing from there and we'll make sure that they do fit our that the tip fits our gauge like they should all right we've got our tool nicely honed got a nice sharp cutting edge right there and then I touch the tip up just a little bit we broke the corners with the hone and if you look at our acne gauge right there you're looking for the number six all right and then we got it we got to make sure that we're using the right in out here because this one is for number five ground for a number five anyway so there you can see it so fits the gauge just like it's supposed to should not wiggle around back and forth it should fit it perfectly like that and then also whenever you're grinding the threat profile you use this part of the gauge like that to make sure that you get your proper threat profile and then you use this side of it so that you get the tip of your tool ground to the proper width for whatever pitch thread that you're cutting there okay and then here's here's a little comparison against the tap also see it fits there good so we'll go to the lathe and set this tool bit up and start cutting our thread all right we're gonna get this tool bit set up first thing take note we got the compound I've got it swung to the left here on 14 degrees we'll use compound in feed alright we're gonna go we're gonna start with our tool bit I'm using an Armstrong t2s tool holder here I'm gonna go ahead and stick this in there this is not squared up in any way I'm gonna go ahead and just tighten it up nice there and first thing we'll do is go ahead and center it up get the tool height first I'm just gonna use the live Center there to get it adjusted pulpits been ground just a little bit on the top so it should be just a tad low and it is looks pretty good right there alright so the next thing I want to do is make sure that the thread form of the tool bit is square to the shank of the shaft right here so we're going to use our our pitch gauge we're going to square it up on the on the shaft here and we'll run this in and I'm using this section right here and I'm a square up one side of the tool bit looks like it's really really close there that the very tip is off just a little bit so I'm gonna loosen this up looks pretty good right there now the view just so that you can make sure that you see what I'm what I was doing there I think we're ready to go I've got the machine we're running a hundred rpm I was set at six six pitch we're gonna do a little touch off and a scratch and just make sure that we're we're there let me get the tool up close there all right that's a touch off that's our zero point go in mm and let's make a little scratch pass down a little ways and then check it make sure it we're cutting [Music] let me get rid of those chips and then we'll check it with our I've got another threat pitch gauge right here this is for Acme and a number six and you can see right there we're cutting we're lining up one six so we're doing good all right go ahead and come back in here Quebec it to our zero and let's just go ahead and make a five thousand scratch pass all the way down to see what it's the see how it's doing now I will use some cutting oil on this since we're using high speed it'll help it'll help that just a little bit since we're making such a cut here alright that looks like that's gonna be doing doing good here's a little shot at my dashboard setup so we've got this Noga and this indicator set up on the cross slide I like verifying that this zero and this arrow stays the same because as I said before this zero usually changes when you're moving back and forth this this doesn't always go back to your true zero you can be off just a little ways one way or the other and whenever you're threatened that makes a huge difference if you're in you know two or three thousand is one way or the other so once we back the tool out you can see we're plunging the indicator and then we'll go back in and we'll go back into our zero and I can compare that and get some cutting all on the screw 20,000 step to cut right there [Music] [Music] I think one thing I'm gonna change I didn't think about this till now I'm going to take this Center out take that out of that small tip out I'm gonna go ahead and put one of my my better more heavy-duty sinners in there but before I do that I'm going to come on down and reset my zero so that no I'm back in my zero spot [Music] [Music] [Applause] [Music] as we get close to our depth there I'll be sneaking up on it filing the top of the threads because it is rolling a burr over and then start hand fitting it to the screw we are getting pretty close we should be within about five thousandths right now don't think we're quite there yet yep still tight but I don't want to overshoot it either make a spring pass and then we'll check it again still still a little tight so we've got a few more thousands to take out of that thread there so I'm going to keep taking those little light light cuts in there and checking it until we get this thing to screw on there like it's supposed to it took another light cut across there not quiet we're about halfway down that nut all right let's give this a shot now now that feels like it's that's the ticket right there oh yeah look at that man that feels like money I think we hit our mark I'll have to stick an indicator on there I don't even feel any backlash no grease required on this one Tony I think we're good to go here I don't want to take any more out of thread keep it nice and nice and tight like it is right there so what what I need to do I want to do some filing get rid of the sharp edges you know that the corners at the top of the thread or sharp so I'll do a little filing on the ends it hit with some scotch brite to kind of soft it and up brighten it up and then this lady works can be done a little tricky to hold it and try to move it without actually twisting it on the screw see you can see we're moving it there by turning it but see if I can get it to that little bit of movement in the needle there is the backlash it's minimal I'm turning it there see I'm happy with that fit there it's beautiful well there it is polished up after that last clip there but I'm not quite done yet there was one more feature on this that I was actually waiting to do after I had got the all this done all the threading and what Brian had requested is I don't know why he wants this but he wants a 3/8 hole drilled all the way through this thing alright and I could have I could have started on this in right here I didn't want to drill it because I wanted to keep the center in here for my threading so I was going to do that last but it's no problem you net that 60 all Chuck is not gonna hurt this and I'm gonna go ahead and get that that hole drilled through there I'm just gonna go half way will just drill three-eighths half way through there flip it around and drill the other the other half and then once we're done with that then we'll have to set up and we've got a key way to mill here on this side 3/16 key way and we'll get to that alright guys we got the 3/8 hole drilled all the way through just did that off-camera so we are set up in a 5c collet block being held in a 3/4 inch collet and we've just we've got a 3/16 key way that we got a mill right here it's going to be one in 7/8 of an inch long alright so we're just going to use an edge finder to find the center of that right there I'm gonna put me a little witness mark on there just I like seeing where the end of the key ways are gonna be so just somewhere right in that general area right there one seven eight establish the flat that 3/16 key we're just going to bring the knee up until we see that cutter cutting a toll radius all right and it's gonna move the cutter off and you can feel it with your fingernail you'll have a little catch on each side so you know you're cutting the full-width there so you just go half half of your width of the key so we're gonna go we're just going to go up ninety five thousandths one of seven eighths on the Dro I touched the cutter off on the end right there and stepped it off so alright just about done all right we're all done with our leadscrew everything turned out good I'm real happy with the way the threads turned out and always love being able to machine the stress proof material this is 1144 stress proof just real nice stuff to build a machine you know you could you could do all this turn and very easily with high speed tools if you don't have a good carbide inserts it's real easy to machine so this was our there was our print our drawing should I say alright and then so I was going to show you this I forgot to mention this earlier when I was making it so this is this bearing right here this bearing fits right up against that shoulder so I've got this turn for a very light slip fit over that bearing right there okay that's how he wanted that light slip fit and the next component that I got to make is going to be the housing that this bearing lightly presses into that gets bolted to the back of the tailstock and that's going to be let's open up our drawing right here and that's gonna be this guy right here so we got to make this this is the one we're going to make it out of stainless he wants it made out of stainless big just so that it won't rust and that's where it goes bearings gonna fit up in there and the lead screw goes to it like that hand wheel goes on the backside and the nut captures everything real happy with the way the the fit of the thread worked out for me it's just a beautiful fit so close that it tries to chatter on me without any without any kind of oil or lubricant in there does that little chattery vibrating thing all right well that's it for this when we're going to go ahead and move on to our little bearing housing next and that'll be that'll be coming up on the next video okay [Music] [Music]

Channel: Abom79

Views: 634,558

Keywords: abom79, acme, acme thread, tool bit, tool bit grinding, grinding a tool bit, grinding an acme tool bit, acme tool bit, high speed steel, lead screw, left hand, left hand acme thread, left hand lead screw, left hand threads, machining left hand threads, left hand nut, lathe work, manual machining, manual machinist, machining steel, stress proof, tailstock repair, job shop, booth machine shop

Id: PqtAdjXa_HU

Length: 38min 36sec (2316 seconds)

Published: Tue Aug 13 2019