Threadmilling on a manual lathe

[Music] and welcome back let's see how we can make weird features like this this is a 90 degree od threat with 2.5 millimeter pitch and a blunt start and the idea here is to have a router motor in this case it's a it's a crest router motor with er16 call it mount it to the tool post of the lathe and have it either square to spindle or in line with the spindle and this allows me to do [Music] for example thread milling on a manual lathe which is normally done on a cnc mill or on a cnc lathe lesser known on manual machines but it was done for some manual production leaf there were thread milling attachments i'm not the first one to do this i'm not the last one to do it i didn't invent this but that's my take on it now so let's look at the look at this mounting block here first hide this how i made this and then set it up here on the lathe and do some thread milling okay i started by laying out some lines on some 50 millimeter mild steel and bandsaw the shape out face milled it to size use a rotor broach to remove most of the material from both sides because the cutting depth was not enough and then i used the wall hopper boring head to cut it to final size then a little bit more band sawing to get it to final shape some drilling sawing tapping and that's the end result there is really not much to this part i haven't done much deburring on camera lately so why not do this one we'll start with a die grinder and always go climb cut never go conventional cut against the rotation because it will dig in when you go climb cut this direction it will always ride on the material not cut into it that way you get a very clean and easy controllable chamfer okay i deburred everything that i can reach easily with the die grinder and it's already handling way nicer this keyway slot here needs needs some more work this is needle file work and we will just hit it like this with a file go 45 into the corner so we get a nice mitered chamfer in the in the corner same for the the edge that that touches it always for also 4545 compound angle and create a nice mitered chamfer in there hey you're dragging the file on the backstroke yeah i'm following and i'm releasing pressure and i drag it back same here filing all the way up into the corner or compound angle falling over the corner here same here balling over and mitered chamfer all the way into the corner this doesn't have to be a science project this is just a very very utilitarian tool but i still want to do a decent job [Music] take everything that we did with the dive file with the die grinder and put a secondary chamfer on there so it's almost a radius this goes very quick this takes only a few minutes and with what we're about to do doesn't need to be super tidy um the magic will come later there are two apprentice marks in here and somebody slip with the diagram mine minorly here but we'll go with that we will leave it like that some 200 grit sanding sponge usually i have way coarser ones because they cut faster but i'm out of them so i have to use the 220 stuff then we just hit every edge corner and also the surfaces with the stuff and this unifies everything this just makes it look uh crazy nice and this doesn't take long we will put some screws in the threads so don't uh send blasting in and threads don't go together all too well so we protect these with some scrap screws okay that's that that's the touch everything with both hands uh cut yourself test if you still cut yourself or hurt yourself you didn't debur it properly that's like the guy stand next to the cannon that he cast on its first test fire and if it blows up well didn't cast it good enough cannon blowing up is of course worse than cutting yourself on a on a badly deburred part but still same idea not crazy did the the sand blasting on these parts and they don't look too shabby a little bit grummy from my finger from oily fingers but that's not an issue we take those screws out and i changed my mind again and i'm going not to leave it blank metal i'm going to black oxide it cold blue this part is small enough and the steel is a mild steel so or low carbon steel so the black oxide will will work just fine on it and the [Music] the blasted finish will will make it work very nicely let's let's put on some gloves because we're working with some with a number of chemicals here first one is an activator this is an acidic activator that attacks the surface of the material and makes it more susceptible to the reaction of the actual cold blue okay first we wash the part down with some acetone then there is a thing about the chemicals i i don't take a brush or something and dunk it into the chemicals i'm going to use especially in the cold blue because it will cross contaminate back from the part into the into the container and just ruin it especially with the cold blue when you get any oil or something like that back into the cold blue yeah it doesn't work that well anymore so we take i i use a cotton swab clean cotton and i just put some of the activator solution on there and i wipe down all surfaces of the part that are relevant eye protection of course it's an asset and the cotton swab technique works exceptionally well i had best results i tried different other ways to do this and everything else just ended up being a blatant mess and this has proven for me to work the best for these small parts that i usually do so we hit all surfaces nice and even and the part needs now to rest a little bit about i think they say something like five minutes so the acid can do its magic on the on the metal now a few minutes later we take our our part and some distilled water and we wash it wash the the activator solution off my experience it just needs to be kind of cleanish you don't need to dry them the the blue the cold glue works in conjunction with the water just just the same it just gets a little bit diluted that's an issue fresh cotton swab for the cold blue oh let's take let's take a little bit more of a cotton swab here cold blue selenium dioxide based cold blue there is no special brand that i recommend just get something get it on the cotton swab and here we go and there is the reaction then we just wipe down the whole surface of the part in a timely manner and that looks already pretty darn good if you put the part on a on a hot plate and heat it up a little bit maybe 50 degrees c or something like that uh the reaction gets even faster sometimes depending on the alloy of the steel you also get a bluing a real blue and not a black or dark brown you take your denatured water again and you rinse the parts off and then you immediately need to oil them i like to use a spray lubricant because they are usually very very thin and go in every corner that's what we're going to do now take a fresh piece of paper i will rinse the parts off camera and you have to be a little bit quick after rinsing because the black oxide is basically rust and rust in combination with water means more rust so you don't want to leave the parts sitting around like that forever otherwise it might be in for a surprise okay here's the spray lubricant i use some some oil and i spray the part down uh extra care taking on threats and bores you don't get a rusty surprise in there and now you have to to leave the part sitting for some time uh the freshly built black oxide which is an oxide layer is porous and it will will soak up some of the oil during that time and create not exactly a rust protection but the parts don't rust immediately usually these parts after after you rinse them and you spray them down with oil they seem to go a little bit darker in color more towards black or bluish black which which is nice okay uh the oil has soaked in i i wiped it all down and now it's time to put this to use and when i bought this this 43 millimeter bore which is a euro standard for these router motors and also hand drills electric ones have this 43 millimeter shank i made it basically zero on zero fit so you you cannot assemble this uh you would have to to pound the screwdriver in there and spread it apart which is uh you don't do that i added a set screw in the center here which allows me if you back up the clamping screws a little bit to spread the this clamping element apart a little bit then it goes on very nicely you can you can adjust it then you back off the screw then is already basically held in place you can almost not move this by hand or in fact you cannot and then the only thing that's left is to tighten these screws like like this just give it a little bit of torque no need to crank down on it like crazy these are only m4 screws and that way this clamping collar if you if you make them right on size you need basically no almost no clamping force on the screws to make them hold properly screw the key in here and we take one of our multi-fix holders this happens to be tool number 15. okay so we put this in the multifix holder we press the holder up against the the the other holder and we we screw it down and there is another design decision this this key which is the clamping latch does not touch the back of the multifix holder this face of this this holder this touches instead on this face and this gives basically like a dual face contact like an hsk taper you have contact here and you're clamping here on on the thickness so you add stiffness against bending load down and upwards a router motor i'm using is a crass f f m e dash p p stands for precision no joke it's really precision variance off of this router motor and the cool thing about it it uses compared to normal routers which use some some stupid proprietary collets this one uses er16 collets which is a big bonus in my book because er collets are readily available in all diameters which i rather call it usually not so yeah that's the package um or the this this router motor goes from 5000 to 25 so we have quite a speed range to play with gets super loud above 20 000 rpm because it's a brush motor brushed universal motor but there it is there is the live tool i got the i got the the router with a multi-fix holder mounted on the lathe and i'm using a dial test indicator in the spindle of the lathe to to to center the spindle of the router in relationship to the lathe spindle especially on height on diameter it's not as critical because we can later touch off and yes i'm indicating we're on really rotating indicator and we will have some indicator sag but with with this relatively short overhang shouldn't be that big of an issue we're not having or we don't have a noga arm hanging out that far and indicating that way in this case it's probably like 20 or 30 micron of stack and while we're here we can also look at the runout of the router and that's well within 10 micron which is for a router motor not too bad let's get rid of the indicator what what can we do with this we could chuck an end mill in here and drill and mill features on the end of a part uh cross slots bolt hole pattern if we put if we put the dividing disc on the spin on the back end of the spindle of the lathe we could drill for example uh hold both hole patterns or stuff like that but i didn't do that i didn't build this for this purpose i'm not too interested in that my main idea was thread milling i want to do thread milling on the lathe every cnc guy everybody who runs a cnc mill or a cnc lathe with a z-axis c and y-axis preferably knows about thread milling but why not do it on a manual mill and i'm not the first guy to do this uh this is not my invention but uh that's uh ah this is my approach to it let's not say it that way so thread milling you have a really rotating form cutter that has a thread profile and you have a spinning work piece and you have an overlaying cross feed lengthwise feed just as you would single point thread only difference is that we don't let the tool that the cutting motion of the tool is not is not relying on the surface footage of the part rotating the surface footage required for cutting is created by the tool itself by spinning that means that we can have the part rotate super super slow like 1 rpm and still get a very nice thread and the main reason i want to do is because i have to do small threats small internal threats they have often basically no lead out and threat milling with very low speed rotation and lengthwise allows you to control the depth super precisely and super carefully so let's try this out let's chuck up a thread mill i have two different kinds here and try this out i have those two styles of thread mill here this is a single point thread mill it has only one 60 degree point and four for cutting edges which doesn't matter in this case we have one row of teeth here and this allows you this is not this has no built-in pitch so you can use this for multiple thread pitches this one goes for threads from m5 to m8 that's a function of the clearance of the of the cutting edges if you try to cut too large of a pitch with this you run out of of clearance on on the cutting edges so this is basically good to a to a 1.25 millimeter pitch the other one this one has multiple rows of teeth and this has has the the pitch built into it it's m3 so it's 0.5 millimeter pitch and the idea behind these is you go down to almost to full depth that you want to thread and you feed out you do one spiral one uh one rotational motion that has the pitch associated with it so you go down you take one rotation with with the c motion following the pitch in this case 0.5 millimeter then you retract to the center of the board you go out and you have you have your thread cut in one go that's basically the idea behind these these are these are super fast with this one you have to spiral down the whole thread or spiral out most people prefer to go to to the bottom of the bore feed out and then spiral out because of the chips packing up in the bottom of the thread i used this style on the on the daytron network they work quite nice so let's check this one up on the in the lathe and cut cut a little bit of a thread get the cutter chucked up in the in the router spindle here we're going to run this at 15 000 rpm first we will chamfer the end so i will cut away from the chuck that means i will have the lead screw in the normal feed direction but have the spindle runner in the reverse the the routers the the cutter here doesn't care about the direct transportation except for climb cutting or conventional cutting with going reverse we are conventional cutting which is not ideal but it is what it is so we we start by chamfering the end now we move in let's say we want to cut 10 millimeters of thread we will cut a relief with this cutter we will just plunge in straight without any lead screw motion okay now we can feed in and engage the lead screw [Music] [Applause] and we just cut a beautiful 0.5 millimeter pitch thread instead of one millimeter pitch because i was too dumb to check the the gearbox of the lathe but let's let's finish this quickly [Music] due to the fact that i messed up the uh the pitch the feet pitch um we also cut this thread way too deep because i went for a five millimeter minor diameter and that's about 0.5 millimeter too small that had the cutter remove a lot of material it was not necessary so let's flip the part around and give it another shot [Music] [Applause] this is most likely not deep enough [Music] because those shrapnels those single points thread mills don't have a corner radius the depth of cut is not what you expect them to be there we go a little bit a little bit too yeah it's okay it's not terrible nothing to be ashamed of but now i know that for an m6 thread with this cutter i have to go 4 1.5 millimeter diameter reduction because the crest of the thread is not rounded so with that knowledge we should be able to just drop down the cutter into the material or 1.5 millimeter diameter reduction and cut the thread in two passes one roughing one finishing pass let's try it towards the chuck uh climb cutting situation [Music] [Applause] there we go i forgot to jam for the end so let's do that now let's see should fit hopefully otherwise i will edit it oh there we go uh yeah about the same fit as before and you saw me i turned the spindle off a few at a tiny amount before before i pulled the tool out and i spun the chuck by hand until i hit my exact c c location on the digital and this allows for exceptionally precise length control on the thread and no lead out just retracted the tool um i'm very optimistic that this might help me in the future with some some of the crazy parts that i do with an m 2.5 threat with no lead out internally of course and the finish is also not it's not excellent the the spindle motor the router here has its limitations rigidity wise but it works and also these super long shanked this doesn't help either i switched to the other style of thread mill and the idea now is the the lead screw is engaged i set the lathe to 0.5 millimeters pitch and i turn the spindle a little bit counterclockwise to take out all the slack in the drivetrain of the lead screw backlash is just something you have to take into consideration with a manual leaf and now we will just plunge in to full depth after we touched up off on the od and then we will have the lathe go reverse and feed out [Music] um [Applause] in theory it would be enough to take one revolution but i think it's better in this case to just have the threat mill come off the threat completely and act almost like a spring pass itself and there we go that's an m3 thread a little bit on the tight side the other thing you can do with these thread small you can start here and just feed in like this does work the same but then you don't take the advantage of of the multitude of cutting edges here so both things work that's the that's a multi-tooth cutter but we can do more crazy things with with uh with something that is a live tool on a manual lathe okay and since i have the deckless one tool kind of grinder now i'm able to grind very fragile very small very precise tooling so i tried to grind a a six millimeter od thread mill which kind of worked both are high speed steel and and both are fourth looted for cutting edges and i also ground the tiny one with a two millimeter od on front here let's get this out of the way and this one is also for fluter you can see the tiny relief flats on the back this this is really this is hard to grind i will i will make no i will not lie about it this this is tough to grind um you see it's hard to see the grinding wheel i'm using a tiny grinding wheel because i don't want to grind into my collar the grinding wheel breaks down quite fast you have to dress often uh it's just takes some practice in carbide it might be easier using a diamond wheel or in high speed using a cbn wheel i was using a tiny aluminium oxide wheel which broke down basically immediately but still works i can grind these now myself from scratch [Applause] that was a test cut with the larger six millimeter thread mill that i ground and it could be cuts actually beautiful this ride is a little bit loose because i i took the the full depth in one cut and didn't do a test cut beforehand but yeah it works cuts nice and freely so obviously the s1 grinder gives me the capability of grinding a functioning multi-flute thread mill let's try the small one to mill a three millimeter thread i fully expect this to break so okay let's see what we created here probably a mess a little bit sloppy but it it it threads in it's sloppy because uh when i tried to touch off on the inside of the boar uh i think i i touched off a little bit over ambitious and that way made it way oversized let's mill it open and have a look i took the part and melded open to about half half the thickness and you can see you can see the large m6 thread out here with one millimeter pitch with a nice fully formed v which the correct thread profile would not have the correct thread profile for a six millimeter one millimeter pitch thread would have quite a substantial radius here in front of of on the root of the thread this is a full profile threading in search for one millimeter pitch and this has the correct radius here thread milling with those single point uh geometry does usually not create a hundred percent gauge gauge uh fit thread the thread gauge will fit and the no go gauge will also not fit if all the diameters are correct but the thread profile is not dead on so let's put on some more magnification and look a little bit closer that's a lot of macro but at least we see something let's take this part this is my toothpick here you can see the the one millimeter pitch thread profile and in here that's the thread the 0.5 millimeter m3 thread which is a little bit oversized let's find an m3 screw and place it in the thread here you can see that the the screw the pitch of the screw matches nicely with the pitch of the thread which is a given because i set the lathe to 0.5 millimeter pitch but also the the profile of the screw goes nicely into the profile of the milled thread with a little bit of gap because well it's oversized but i'm i'm pretty pleased i'm pretty pleased about the ability to thread mill and also grind my own strap milling cutters here's a close-up of the the larger thread mill that's the cutting surface and here's the clearance angle to the back four flutes and i accidentally undercut the head of the the milling portion here quite a bit in an ideal case this diameter here would go straight up to the cutting edges all the way this floating cut here this is okay this can go into the shank but this neck here this is not ideal i have to find the right way to grind this without necking into there that's the smaller thread mill it's a three millimeter shank high speeds both of these cutters are ground from high speed steel and the neck the necked down portion here is about i think it's one millimeter and this cutting portion in front here is two millimeters and as you can see it all gets all fully you can see all of this gets all fully small and this is on the edge what i can grind on the s1 without any additional magnification and even for this a microscope on the grinder would be crazy useful and i i mean a real microscope would be nice not one of those video microscopes i usually prefer an optical microscope but i might try one of those video micro microscopes with the built-in displays just because they are cheap as dirt but uh yeah this is promising there is another application that i want to use this for and that's machining pvc pc pvc is is easy to machine it's it's soft but the problem is it's on a manual leave it it's close to impossible to break the chip delrin is not an issue you can run a feed and tool combination that will break the chip in delrin super nice and super short almost like brass but in pvc the the feed has to be that high that it's not controllable by a human being anymore on a cnc machine you can run the feet high enough to break the chip but not on a manual machine if you want to hit any any length tolerances or something like that and i i yeah a lot of people recommend to to use a dust extractor to to just catch the long stringy chip off the lathe tool that works but then you have then you have this this 25 and a half kilometer long chip rolling around in your shop vac and clogs things up and that's not ideal too um so i considered if if if we can't break the chip by by increasing the feed why not just make an interrupted chip with a milling cutter this uses to be a six millimeter four flute roughing end mill and the this this works [Music] [Applause] [Music] [Applause] [Music] so so oh yeah this is cool i like this i will use this for producing these parts and this part was even only held in in the street shot check with the gripper jaws on very little amount of material so the cutting forces cannot be very high but the router motor bogged down this is like a thousand watts one kilowatt intake intake power consumption of this router motor uh spindle power is significantly less because of losses but still bogged down so we're taking a substantial amount of material off in a reasonably short amount of time we can also do weird things like orient the the spindle 90 degree to the spindle of the lathe and cut features like that i have a 90 degree v-bit in here and i set the lathe to a pitch of 2.5 millimeter so let's see what we can do with this and when we remove such the such large amount of material the low spindle speed of the lathe is rather important uh think of having your um your power feed on the mill go too fast and that's what would happen here too especially on a single point cutter like this on a d bit these are not especially known for uh for a high material removal rate but we can cut features this way too and you could even do shred milling that way but it's not ideal um i think you don't get the proper profile i think you get some some kind of a weird recutting effect but don't quote me on that but you could for example cut oil grooves in a part especially if you set the lathe for very high pitch rates i think the the mco here tops out at four millimeter but if you switch some gears around in the in the some change gears you can get it definitely to run higher pitches uh you can cut oil grooves on the inside with a ball end mill a lollipop end mill that has a 240 degree engagement uh possibility uh you can cut you could you could even mill square threads on the outside of a part or using a t-slot nah a t-slot cutter on the inside doesn't work because it has no clearance to the bottom it would deform the profile heavily so it has definitely its limitations you would have you would need the ability to to tilt the spindle to do some things also for thread grinding on the lathe you would have to tilt the spindle but i'm not after that here on this machine um i need this really primarily for uh thread milling small diameter threads this is just fooling around now which is also fun and important to do sometimes because you you gain a little bit of confidence what possible so i hope you enjoyed thank you all for watching and i'll be back you

Channel: Stefan Gotteswinter

Views: 102,863

Rating: 4.9703002 out of 5

Keywords: threadmill, threadmilling, gewindefräser, gewindefräsen, emco super 11, super 11, super11, emco, kress, livetool, live tool, angetriebenes werkzeug, agw

Id: 6_1Nlf-X4bw

Length: 45min 53sec (2753 seconds)

Published: Sun Jul 26 2020