Compound Lead Screw for American Pacemaker

[Music] so this is my drop shelf here where i kind of go and always scavenge for a piece of material to make a project i've been digging around and i found this piece right here this is actually this should be stress proof i can always tell because it has a darker color than just standard 1018 cold roll and i'm pretty sure that that is going to be stress proof what i'll do is i'll go to lathe and i'll just make a face cut on it it'll confirm because stress proof or 1144 is the grade is a free machining material so it's going to chip a lot easier than a gummy material like 1018 so i'll just verify that it's bigger than what we need because it's inch and a half but i don't have a smaller piece in there of stress proof and that's what i want to use this piece right here that's just regular cold roll right there so it's going to be gummy stress proof is a great material for making component parts and that's what we're going to be doing i got another big piece of it standing up there that's always the indicator too it's got that that color of paint sprayed on the end of it so i really wish i had a much better inventory of drop and just random different size materials but this is all i got to work with right here we'll put it in the chuck and see if we can verify it i'm pretty sure that is stress proof right there [Music] [Applause] oh yeah a lot finer chip [Applause] a lot finer chip than what you would get from a like a 1018 [Music] [Applause] all right so that's going to be that's going to be our piece of stock that we'll use to make our new lead screw there it's a little bit longer we need so i'll be able to we'll be able to just chuck it up i'm probably going to cut down we got a hole drilled on both ends there so we'll uh we'll leave we're going to leave it big on one end because my plan is to actually we're going to do all of our fine turning over here on the victor because it's going to just be a little bit easier to do here and i think we're going to go to the monarch to do our acme threading [Applause] [Music] just go ahead and clean the face up and now we'll go ahead and pull the shaft out the length length that we need and what i'm going to do is go ahead and turn it all the way back to probably about this area right here probably turn it to there or three quarter diameter so we want to stick it out about 10 inches and then you'll cut the center in the end after you chuck this i don't ever i don't ever machine the center with it like this up close because once you pull this out it's going to throw it off some so i like to chuck the material just like i'm showing here let it chuck it in its natural position and then machine the center in the end so that it's running true with what it's chucked right here so [Music] [Music] [Music] [Music] [Music] we're getting close we should have about an eighth of an inch still to come down going from one and a half to three quarter so just taking one-eighth passes each time so yeah we've got about a hundred about a hundred and twelve thousandths get right now we're getting about one thousands taper from uh from end to end there that should straighten up as we get down to our finished cut so i think what we'll do we'll take one more rough cut across here and then we'll split our finish into two passes that way they make it you have equal tool pressure on our finish cuts [Music] [Music] all right we're going to slow our feed right down five thousandths it should leave us about 20 thousands to remove so we'll probably take a 10 and a 10. so we've got 25 thousandths to come off so i'm going to split it we'll take a 12 000 pass and then mic it and we'll we'll just bring it down to exactly three quarter and let it be there all right this is going to be our finished pass [Music] [Applause] [Applause] [Applause] all right so we've got it turned where i want to we're going to go ahead i've got a radius tool in here this is 3 16 wide full radius insert so what we're going to do is the undercut here which is what we'll have to have because we're going to be doing a left hand thread so we're cutting from the left to the right so we'll go ahead and undercut this is quarter inch so it's a half inch diameter down in the bottom and that'll suffice too for the acme thread so we'll just go ahead and come down here and do a nice wide undercut there a thread relief so we can start our thread using my 12 inch hook rule set the location there so hook the edge of the insert line up the end of the shaft right there right there on it move it down to eighth of an inch 125 thousandths that'll bring us to our 3 16 width on the factory shaft [Music] you guys see how nice that stress proof machines gotta love a free sh free machining material makes it a joy to cut all right that's 240 go ahead and clean up the center here what i'll do is go ahead and let's go ahead another 10 and then turn it to the other side easy does it there's our undercut and on the end of the shaft i want to do a nice big chamfer there let's see we'll uh speed this one up son something along that lines right there break these edges off as well [Applause] i left that one thousandth big so we're just using some 220 emory paper and just polishing it down and that'll make it look real nice too oh yeah right there on it still has a little bit of warmth to it too so it might shrink a few tents as well that's pretty much there though all right i want to show you guys the tool we're going to use to machine the thread there so i have invested in carbide insert and we've got a new tool holder here as well a couple of reasons why i went this route for one i want some new tools for the american pacemaker but i can also use the uh the one inch shank on the monarch as well the the one-inch shank tools will not work in the victor lathe and that's another reason why i'm going to move the shaft over to the monarch to cut the acme thread over there but i'm gonna be you know picking up some new tooling for the pacemaker to have down there and this one was a good opportunity to uh to get this guy right here and i did get the left hand tool and this is the uh it's the 54 series insert so it's the big boy and i ordered the actual insert made for a five pitch acme thread okay so pull one of these guys out of here so you can see it tool flow brand made in usa you see it's a pretty good size insert and that's going to be made right there for number five acme thread okay there's the tool holder right there really good quality stuff these are made in usa i believe they're made over in texas uh tool flow and you have a lot of options whenever you have these types of tools like that tool flow is a good source for some of these larger on-edge inserts in different thread profiles grooving profiles and even radius tools as well so you know i don't it's not just a one tool one insert shot there i can invest in different types of carbide inserts for this tool and be able to put this to work over there on the pacemaker i did not get the right hand just simply because i needed the left hand to get going right now so i just went ahead and got the left hand and that's what i like to use whenever i'm cutting a left-handed threads because you're going you're going from the left side and we're going to be going to the right and your pressure should be against that side of the tool there most people you'll see whenever they're doing threading left-hand threads they're using a right-handed tool meaning the inserts over here and they're cutting that way and there's not anything on the back of the insert except for the clamp there that's supporting it so that's the proper way to do it if you're going to do a left-hand thread is using a a left-handed tool going from left to right but anyway new tool for the shop wanted to share that some good quality stuff that tool flow makes and hopefully this is going to get the job done good for us now alternatively let me move this over and show you you do not have to have a carbide insert to do acme threads this is out of my granddad's tool box right here and this is where not only he but my dad used to put the acme tools you know and i've used them many times over the years as well so you just you'll have to have you a good acme gauge just like this guy right here this is a nice sterit 29 degree screw thread tool gauge but for acme and it has you see all the different numbers up there so use this gauge right here to grind to hand grind or if you want to use a tool grinder your acme tool out of a piece of high speed steel and this is what this is what many people have done throughout the years so you'll grind the tip of the tool to match so there's the number five right there so the width of the tool should match the width of the groove up there for that thread pitch designation and then you have this gauge here that you can use to make sure that you have your tool ground properly there and you also have one there you can use you can put this up against your work piece and use this to square up your tool against your work piece there all right so another good way to do it for you guys that are learning about this shop work and you're trying to do this stuff yourself pick you up one of these acme thread gauges right here they're not very expensive you can probably get them used off ebay and some inexpensive high-speed tools and practice practice grinding these right there and you got you some acme tools all right so but we're going to go with the carbide insert for this job let's go down there and get her set up went ahead and got the insert loaded up into the tool there and one of the other things i wanted to mention is another reason why i like using these whenever it's possible is if i end up chipping or breaking this insert the tool is in the same location it's not like when you've got to have a high speed tool clamped in the tool holder you got to take it out and sharpen or grind it and then you got to line it back up with your existing thread in most cases as long as your tool post doesn't move if this thing snaps is that all you got to do is just take this in this insert index it around or stick another one in there clamp it and it should be in the exact location of when you were cutting your thread in the event that this thing snaps and it is likely to snap or break during the machining process but uh we'll just have to see if we're gonna get through without having to worry about that but anyway there it is it's a good looking tool i really like that all right we're getting set up in the monarch here get this guy indicated now i am chuck straight into the the jaws here as in making full contact i'm gonna i'm gonna indicate this and see if it's got it in a pinch or something because sometimes when you're chucking a long piece like this it'll actually kind of have it cocked one way or the other and then it's forcing this to run out on this end in that case you just put some pads there on your jaw so that you have a narrow contact point we'll just indicate it and see what it's going to do loosen your lows tighten your highs you're just pushing it to the center once you get it close just tighten your highs and get the slack out of the jaws and notice i am indicating the area that we're going to thread try to get that as true as possible half a dowel too far a half a thou that's pretty good right about there let's see what we've what we look like got to turn the power on first so we got a little run out down here on this end and it could have been on me too it probably moved on me after all that turning we'll put the center in there and see what it does all right we've got our center in there tail stock tight i'm getting a little bit so we're getting about a thousandth to a thousandth and a half there and that's gonna be we're just gonna run with that i think this is gonna work out good right where it's at so a couple other things to note since we're cutting our acme thread i've got the compound swung clockwise to the left since we're cutting a left-handed thread if you were cutting a right-hand thread you would turn it the other way i do have it set on 14 degrees uh some people tell you put on 14 and a half the books might say 14 and a half i put it on 14 so that the tool the left side of the of the cutting tool will help clean the thread as we're as we're machining it we also have the compound indicated so we've got we've got our tool right here loaded up in a tool holder and what i have done let me back this out so i don't land on the tool put an indicator here against your tool run your cloth crawl slide in and out i like to make sure that my tool is perfectly square to the work piece right there so i always indicate my tools nice and square so i believe that's about it we're about ready to get started on this this is what i'm talking about squaring up your tool right here use the dial indicator to make sure that your tool is nice and straight and square you're not at an angle you want your tool to be square to your work piece i also wanted to show you i've been down here figuring out all the the uh the numbers that i'd like to see for the thread that we're cutting which is uh you know five threads per inch acme okay so i'm using the machinery's handbook to get this information so this is page 1349 and i am using the 20th edition this is the one that i just keep out here in the box and this chart right here you've got all these charts right here that's going to give you all of your information that you need to know or figure out for whatever it is you're cutting this chart right here table number five is going to have all of your class classifications from 2g to 5g all of your threads per inch in here i'm sorry diameters this will help figure out your pitch diameter tolerances but this chart right here table number two a if you go through this and and do what it's saying for the formulas here this will give you all your information that you need to know for the thread that you're trying to cut so i've gone through here and that's just exactly what i've done you know everything from our major diameter nominal size to our pitch in our case our pitch is 200 thousandths figure out your pitch is easy you just take one divided by the number of threads in our case it's 5 equals 0.2 and then once you have that info you can go through this chart and figure out everything that you need to know your your pitch diameter minor diameter pitch diameter max pitch diameter minimum minor diameter maximum minor diameter minimum and i've also even got your pitch diameter tolerance for both a 2g and 5g fit i think this is all right right here i don't do this stuff very often and when you're not when you're not doing this type of machining and threading on the daily basis or even the weekly basis maybe even the monthly basis you kind of forget this stuff and you have to go back in the book and reread it and refresh your memory on how to figure out these numbers and some of this stuff isn't really you don't have to know all this stuff you can certainly go to the lathe set the tool in there start cutting using a gauge like we're doing to checked out but it's good to refresh your memory on the mathematics that's involved with vigor and anatomy thread and that's just what i'm doing here i'm just trying to refresh myself and be familiarized with the numbers that we're trying to hit on our screw we want to we want a a tight fit between our our lead screw and our nut and that's what i'm going to be shooting for here okay so anyway i just wanted to kind of point this out if you're trying to learn this stuff too get your machinery's handbook open up to this page and just start reading this and figuring it out you know just write down a random size that you want to figure and go through the formulas and do the the formulas that it's in which it's telling you and figure this stuff out and that's a good way to learn and understand more about an acme thread or any thread for that matter we've got our tool touched off there also note on this end here i turned this down to our minor diameter you can use this as an indicator whenever you come across and it touches you know you're going to be very close so let's uh let's give it a scratch and make sure i'm on the right pitch all right i'm just gonna back out we're gonna use this guy right here acme thread gauge and it's looking like it's lining up on five so i think we are ready to go here come back into our zero and let's uh let's make a cut [Music] all right that's looking good i'll try to get you a nice tighter shot than that [Music] so [Music] so [Music] [Music] [Music] so [Music] so [Music] [Music] one of the features i love using on my monarch is that you have a solid stop there made for threading so you have this this pin here that you engage and this sets your zero for your cross slide so whenever you back out the tool and you go back in it comes to a positive stop so your tool is going to end up in the same position every time back on zero and then you use your comp your compound for your end feed there [Music] [Music] so so [Music] got to be quick it's a coarse thread so it's easy to miss the dial if you don't line it up right not gonna say i have not done that disengage retract the tool bring it back down to your thread relief go in a little bit more on your top slide and get ready to engage so i'm engaging on any number one two three or four so basically every other line all right we're getting there nice and easy i'm just taking about five thousands of pass there so we can just kind of sneak up on our on our minor diameter that we're gonna finish out at [Music] so [Music] so [Music] [Music] so [Music] [Music] [Music] [Music] [Music] [Music] sip of coffee [Music] get real close to our minor diameter there's a little ways to go [Music] [Music] see i don't know what was doing there it acted like it was trying to dig in what's up with that what's happening there i'm not that buddy [Music] [Music] i think what's happening it seems to me like it's trying to pick itself up and pull itself up on top of the tool there to me that's i think that's what's happening it's only in that one spot isn't it well it's because it's getting further away from the rigidity here of the chuck it's out here it's not supported very much that's got my thread screwed up now it's not going to be very pretty [Music] [Music] this has turned into a really unfortunate machining op for me and it's actually a complete screwed up mess now and really frustrated at this machine on what what is happening here because there's no reason for it to be doing what it's doing you know i'm taking i'm coming by and i'm just i've already the threads already screwed up so i already know i'm going to be making another one but i'm just continuing on with this so i can try to figure out what my depth is and how it's going to turn out you know so i'm taking 2 000 to pass coming down i'm just trying to clean it up two thousands two thousands and then i come in and take another pass here and all of a sudden it just digs in it's like it just sucks the tool up in there and it digs in and it just chews it all up and it should not be doing that and i'm trying to figure out that's why i'm continuing to just mess with it and cut with i'm trying to figure out what the machine is doing and i can't figure out exactly there's a lot of variables on what ifs this or that but i'm not quite sure yet but it's really frustrating and there's no reason that that should have happened right there just like that last pass i mean just dug in you know you're basically right on your finished pass because i've been checking it with the with the nut here and i had it where it was trying to screw on but you could tell it was tight so you know a few more thousandths and it should be out of there and then all of a sudden instead of just taking a couple thousandths the tool just digs in and it just removes a whole bunch of material now when i go back in there with the tool it's not to the depth that it was when it dug in so it's something's moving there's there's something happening here it's pulling it in it's not staying consistent so the monarch has completely let me down on this job right here and i'm really disappointed in it and i already know i'm going to order some material and we're going to try it again i think on the next one though i'm not coming back to the monarch since it let me down we might just turn it and machine it right here on the victor well the machining of the lead screw there didn't quite go as planned i'm definitely having some issues here with the the monarch lathe very unfortunate uh this this machine's always been very reliable for me but it has been quite a while i can't remember last time i've cut some coarse threads over here it's been it's been quite a while but it's it's doing something and i can't pinpoint exactly what's happening here yet i really don't know but there's a lot of what-ifs and could bes and issues that might be causing problems so it seems like the tool doesn't want to line up perfectly every single pass now you saw most of the passes it was doing great but then sometimes you come in there and it's like either the tool gets sucked in too far and it starts digging in or it's trying to cut heavy on the left side of the tool meaning that the lead screw here doesn't seem to be perfectly engaged in sync every single time and whether that's the problem or not i'm not sure i'm just suspecting that that's like could be one of the issues here because there was cuts where once we got to about halfway point it started cutting very heavy on the left side digging in okay so instantly screws your thread up so i don't know if it's if i've got too much backlash in the lead screw here for your cross slide i know that this needs attention you know it hasn't been messed with in probably decades honestly but i don't know if i have another issue dealing with the lead screw with the quadrant gears or something not staying sync like it should be while you're doing this honestly i don't know but i really don't want to chance it again coming over here and trying to machine another lead screw and dealing with the same problem i think what i'd like to do is go to another lathe to do this right here and what i was thinking we could very well come over here to the victor lathe and cut it over here i feel like it would be a good machine to do that but i think what i would really rather do is let's go use our precision matthews lathe we've got a brand new lathe at the new shop i have not used it yet and one of the main reasons i have not used that is because i don't have my tool post mounted on it yet i've been just kind of waiting for the right opportunity to work on that project so i think what i would like to do is pause on this right now i've got material ordered i ordered some 1214 and some stress proof from mcmaster carr so it'll be here in a day or two but uh let's pause on this and i want to go ahead and get my tool post mounted on the precision matthews i have another one of these multi-fix type of tool posts that a viewer had given me some time back probably a couple years ago and i've got it all cleaned up now cleaned up all the tool holders and it's all just sitting there waiting for me to get it mounted onto the uh the tool the compound i mean and get it mounted on the lathe so i think i'm going to work on that project now go ahead and start getting that worked on get it mounted and once i do we should be ready to do some machining in the precision matthews lathe and then once i get my material in and get the compound on the tool post let's use the precision matthews to machine another lead screw and see how that lathe will do you know compared to my issues that i'm dealing with right here all right so i think that's what i'm going to jump on let's start getting a tool post mounted on that precision matthews lathe i'll probably show you a little bit of that project as well but mainly when i bring you guys back i'd like to get back on the lead screw let's get another one of these machines for our american pacemaker all right [Music] [Music] [Music] [Music] do [Music] you

Channel: Abom79

Views: 930,692

Keywords: Acme thread, acme lead screw, lead screw, screw thread, Monarch lathe, American Pacemaker, Tool-Flow, carbide insert, acme thread insert

Id: gEAURyEZcqM

Length: 44min 44sec (2684 seconds)

Published: Sat Jun 04 2022