I love it when our favorite YT machinists contribute on the rest of the community's content. We have a pretty great little corner of the internet with some pretty great people. You're a stud Pi!
Seems like we have a similar strategy on deburring: Step 1: remove blood stains Step 2: debur the part Step 3: check part for blood stains. If any found, repeat at step 1
After telling the story about the maker who stood by his cannon for the first shot, then Stefan sanding and rubbing like mad again and again, he says "not crazy .." and keeps on sanding. Gotta love the guy and everything he does. Kudos Gotteswinter !
There's lots of good guys posting on youtube. But Stefan in my opinion is the most interesting person to listen too. Totally engaging, supremely knowledgeable, but extremely humble...A pleasure to watch.
Hi Stefan. Nice to see the solution to a very old problem for which the model engineer's Guru George Thomas had a much more complex solution. Folks, when you slit into a previously bored hole there is a tendency for the bore to close in. Stefan's jack screw is a very simple and elegant solution. BobUK.
I've never seen this before! Beautiful little adapter and spectacular results. Seems so much more controlled and safer than single point threading. To me as an armchair machinist fan, you guys cutting threads always looks like some kind of ballet with chainsaws.
By using this same router setup with 2 flute, carbide wood-routing bits, you can make amazingly-accurate lathe cuts and deep grooves in rubber and soft urethane bars. I've used this on motor mounts and suspension bushings etc. The trick is using compressed air for cooling along with a vacuum cleaner. Love the video!
"I'm not the first guy to do this". Stefan, by now I would think just about anything that could be done with a manual machine has been done. IMO the most impressive things done on manual machines are turbine impellers that were done pre cnc. And the interrupted threads on the breaches of large naval rifles. Given the pressures they had to withstand they had to be absolutely perfect. Now if you had a way to run your cross slide at the proper ratio you could make chuck spirals. And I know they had set-ups to do that on manual lathes. Setting the router at the center of the included angle you could also cut buttress type threads. Not germane to threadmilling but in the past I experimented with making roughing mill cutters out of taps. Grind a relief angle on the top of the teeth that gives a flat wide enough that all the flats are longer than your taps pitch. Grind a secondary relief angle. Works fine on softer materials. Not so much on tool steels. I worked with some machinists from Germany and they told me that in the 50s they used to have to make end mills out of twist drills.
I would like to hear more about the difficulty associated with cutting the interrupted threads for naval guns. Can you point me in the right direction to more information?
@@BravoCharleses Sadly no. To be honest I don't know if they where single, double or multiple lead threads. I suspect that multiple lead threads would be weaker simply because of the lead angle of the threads.
In my father's shop back in the seventies we used to do the final grind on hardened threads with a diamond embedded linen phenolic wheel mounted on a tool post grinder. It wouldn't take much off but it made the threads extremely slick. It was set up much like what you're doing except the cutter and/or lap was mounted on a mandrel. The angle could also be adjusted for clearance on larger threads by tilting the spindle up and down in the front. Fun stuff! Thanks for the video!
Wonderful video. Back in the time frame 1880 (and even before that) when electric motors were rare or unavailable there was the English Holzapffel ornamental lathe company .The double ff is no typo. The lathes were foot-powered. They had all kinds of attachments and extra-axis devices. Among the things they would do is mill threads. They would also allow you to e.g checker-pattern a piece or inscribe all kinds of patterns on work. The last Holzappfel was sold in 1920 or so. If you look under "ornamental turning"you will find quite a lot of info.
Putting a router on a lathe's toolpost as a milling attachment is a neat trick. A homemade 4-flute 2mm thread mill bit that doesn't break without magnification is really impressive. I would stick with single flute D-bits below 4mm. I've been studying threads for 50 years since I worked on Brantley Helicopter rotor parts with old 4A & 4B threads called out on some of the rotor drawings. That is tighter 3A & 3B but not an interference fit. The reason for the radius at the root of the thread and the tread relief is to prevent stress concentration. We may worry too much about thread forms. Mauser rifles all were made with Whitworth (58-degree) threads, usually 12 TPI. In the US, we rebarrel them with barrels having 60-degree threads almost every time. They shoot the same no matter the barrel thread.
I have a similar setup and have found that it works great for trepanning. I use an end mill in the die grinder and rotate the lathe chuck very slowly. It's much faster than using a conventional trepanning tool and there are no issues with chatter.
Stefan is one of my favourites. I have to choose between Stefan, Joe Pie, Robin Renzetti and Tom Lipton. There are others of course. The steadfast adherence to practical as well as accuracy and precision is truly an art form and is common among them all. When I want a chuckle, as well as these qualities, I turn to 'This Old Tony' as I'm sure most who are interested in this subject will do. Abom79 is another stalwart - a big amiable kind hearted giant of a man. This is a special community, revelling in an under regarded set of skills. Hand to eye accomplishment is the best medicine for what ails thee.
Its always nice to see a true craftsman doing his stuff Being an engineer ( millwright) for nearly 50yrs I know quality when I see it Great video Stefan Please keep making them Pete UK
Very nice Stephan. I find lots of little embellishments you do usefull to learn. Like using a set screw to open a coller clamp that allows for a precise fit without over torquing a small fastener. Like Filing a precise 45deg bevel junction on an inside corner. Instructive, thank you Sir.
Cannon blowing up < bad deburr for sure. Also, the set screw 'trick'/gimmick is frickin brilliant. I've never thought of that. So simple and amazing. Damn good thinking!
Yes the jack screw a great idea. It's also a good technique for mounting one plate to another with some degree of adjustability to allow them to be co-planar (e.g. DRO scale mounting, to a casting). A jack screw plus a tension screw in 3+ corners allows for a lot of freedom of adjustment.
Watching Stefan deburring a part is like watching an episode of Bob Ross on TV. You listen to a calm voice explaining how simple it is, doing a bit of magic here and there, and yet you get a totally different result when you try it yourself...
I soak up everything you tell us, Stefan and, if I can't apply it straight away, I store it for future use. One thing though which I have found with thread milling tools, is they generate a different form to the shape of the cutter. It's the combination of the tool rotating on an axis parallel to the work piece's axis but interpolating a spiral. The front of the cutter generates a different flank angle. The true thread form should be normal to the helix angle of the thread so the form of a thread milling tool really needs to be modified to take this into account. The trailing side of the form is fine as it is in clearance but the leading side will back cut the flank to form an angle larger than required and the radius will also be generated larger. For threads which are large compared with the diameter of the tool, this is negligible but for very small threads relative to the size of the cutter, it is significant. I have a thread milling cutter for an M2.0 thread which has an OD of Ø1.6mm (the tapping size for the thread!) which will cut a thread either tight (crest of screw same size as major diameter of ID thread) or it's too loose because the female thread form is too wide. Are you able to CAD model a cutter which will generate the correct form when interpolating a helix?
Hi Mr. Stefan, Another awesome and very educational video!!! I am a bit of newer subscriber to your channel!!! I must say you have some very excellent, well detailed and very educational videos i have seen on RU-vid ( i also enjoy watching Adam Booth, Tom Lipton of Oxco tools, and Tubalcain (Mr Pete) as well as the Electrical/Electronics RU-vid creators). I am a hobby machinist (my regular and to pay the bills and hobby full time job is in the IT/computer data analytics field rather boring and straight-forward) and have been catching up on your videos during this pandemic and can honestly say i have honestly learned (at least) 2 or 3 things from each of your videos, either brand new or improving/adding to something i have learned in the past. I also feel your videos have the perfect balanced amount of science, engineering/manufacturing, art and humor! I look forward to seeing all and upcoming videos you will be releasing down the road! My very best to you and all of your family and loved ones throughout the rest of 2020 and beyond!!! also hope that everyone stays safe and healthy during the Covid-19 virus pandemic!!
Nice job as always Stefan. Would love to see a bit on the grinding of the tools, I think this would be really interesting and a good reason to show off your new T&C grinder. Well done and thanks. Jon
I ordered some parts for my hot rod which were not finished very well so I chamfered and polished when i handed the finished and unfinished parts to my wife she said oh my the finished part feels soft as butter now
I have both high quality optical microscopes and cheap video scopes. I put a video scope with built in display (about $49 if I recall) on a magnetic indicator base. I use it in my Emco super-11 and my Hardinge toolroom lathe. It gives a great view of cutter action if you need it. It is also is useful on the mill too. While the quality is not like a Leica scope it does keep your face away from the action. Don't under rate the cheap scope it works and other can see it. Great for demos. I mounted a Dremel moto-tool on my Emco 30 years ago to spin and abrasive disc to cut Hastaloy X . I also had an air turbine with a multistage planetary to spin a slitting saw for screwdriver slots on a homemade gang tool CNC lathe. I also used a full speed turbine (50K or so) to spin very small PCB drills on the gang lathe too. By the way Robin mispronounces Hardinge. He says Harding instead of Hardinge. I noticed you have adopted that too. The correct pronunciation ends with a sound like Hinge (like door hinge) but without the H sound. Please take no offense your English and your videos are excellent. I watch them all. JY
That is really interesting! Done threadmilling on a cnc mill but never thought about doing it on a manual lathe. Allows for so many possibilities! Thanks for sharing!
What a great video. I just have to make one. One thing that I, along with many others I suspect, have trouble with is cutting off. It seems to me that a small assortment of endmills would turn this tool into an almost perfect cutoff tool. Perhaps even a slitting saw could be used in it for cutting off. If I make one I think I will use a reversible motor for maximum versatility. I think this could be a very versatile tool to have at the lathe.
i must say i was impress with the subject of mill threading on a manual lathe , i have an old Colchester , school lathe. & it was never . fitted with a . lead-screw the lathe use's the rack as a threading siystom but as no staring clock. i have tide your idea on my lath &find it works well 7 delivers a good thread. the use of broken taps work's well . & cut a 6. thread to the inch to fit my spindle of my lath internal using a old tap of the right third & pitch. i set the gears to fit the relied third & pitch . & achieve a successful . result. using a old tap as a cuter i would love you to demonstrate larger size sets . such as a 10 mill thread in a 20 mil hole .
Excellent tips. I always learn a lot. I wish my German was as good as your English. I think I have to build one of these. You are starting to cost me money like Tom L.
For right hand external threads, tilting the live tool down at the chuck end should give proper lead angle. A little more restrictive for deep internal threads of small bore. Nice work Stephan and one of my most enjoyed channels.
I just ran 24 parts that needed a 3/4”-32 internal thread to the bottom of the bore. Of course not on a manual machine. But it worked beautifully. Now I’m inspired to try milling trapezoidal left and right hand threads for a self centering vise build. Already located the thread milling cutter. This will also allow any thread pitch within reason. So a double start thread should be doable.
I use a phosphoric acid based "rust converter" for "cold blueing". It makes the same black oxide that soaks up the oil and prevents rust. Dunk it and let it sit in solution, dry it off and oil it. Pretty easy. $25 a gallon in Missouri. The brand name is Ospho. Good stuff and much easier to use and much less expensive.
If you get the polished inserts for aluminium they are able to machine HSS in the lathe. You can cut and shape thread milling and involute rack angled cutters with them to get the correct form then grind the cutting faces. VBGT work well.
There was a study done recently regarding the life of a file used going in both directions vs lifting on the return stroke. The outcome was that there was very little or no difference in the wear on the file for either technique. I don’t remember where I saw this, but a quick search should bring it up. I have been deburring and chamfering for over 60 years and my files have shown no evidence of deterioration. I will say though, that they were never used on hard surfaces, which would probably dull them no matter the direction of application.
There was actually a special lathe, itself called a "threadmill", that I have seen a couple examples of that was used for milling precision leadscrews. It was basically a lathe with a live milling spindle integrated along the bed, that could be tilted to the helix angle of the thread. There are still some using them... Charles River Museum in Massachusetts has one
I just stumbled onto your channel, and I must say I am very impressed with your content and production quality. Thank you for sharing your wisdom. I may not become a machinist but can take some small snippets from you into my studio.
That's very cool! I love it! Please keep experimenting! It looks like a very unique and useful approach for manual machining! Thank you for all of the work that goes into making these videos! Greatly appreciated! :)
Gday Stefan, What a great setup, the new grinder is really working out great, the small tool you made is amazing, I’m afraid my eyes would be no good for doing things that small, really enjoyed this video, thank you mate, take care. Matty
That would also work ideal for face grooves/recesses on a part with the spindle parallel to the lathe spindle. The OD Perpendicular thread milling with the proper profile tool could work good for custom wood screws or metal inserts for plastic/printed parts.
Right after I read your comment, I looked at a drywall screw ;) If I ever need to make something like that I will keep that in mind! The facegrooving is something I tested (didnt film it), and it works suprisingly well, and with the cutter doing a full slotting cut, it also runs very quiet.
Alot of guys building wooden parts in a metal lathe use this method. I've built mounts for a number of billiard cue makers to use a kress and various palm routers in the toolpost on the lathe.
Mentioning the non-breaking chip when machining PVC, at work we often machine down rubber coated rollers (~2.2m long, 170 to 200mm diameter) we use insert toolling on the lathe and we get 1 single continuous chip from that, the surface finnish is great though, competes with what other companies achieve by grinding and doesn't smell nearly as bad
If you set your parts on a paper towel after applying the activator, the bottom side may not get the full effect. I try to use a rack over a small container to catch any drips. If you flip them half way through the process, you can ensure the most even finish. A good cold blue finish is all about the preparation. Great video, and great design for the toolpost router, I am gonna steal the general shape, except I am also gonna build one for a TIG torch.
"Then you have this 25.5km long chip rolling round inside your shopvac...which is not ideal." Come for the precision machining, stay for the dry humour. PS getting chips like that when machining PVC is just...wow! Got to try this.
You could make a yankee screw driver or feed to add or remove wire, cord, or hose to a drum. Acme trapezoidal cutter say 14.5 deg to axis. Cutting the forward and reverse lead angles would be easy. The transition from a forward to reverse say in 180 or 270 degree would require a cam with a cam follower roller and spring pushing the carriage with the cam roller against the cam mounted to the spindle. Hand turn the spindle through the angle. A thought. CNC Swiss mill created a screw for me years ago that drove a piston pulling a vacuum. Battery powered. To give the batteries the longest life the current for the brush motor needed to be constant. Thus the pitch for the vacuum stroke was variable and the return as fast as possible to arrive at the proper angles on the two reversing direction portions at the top and bottom of the screw. The thread follower was a small portion of the thread cut into a revolving cylinder face so that the pitch angle could continuously change. It had to be long enough to jump over the return cut thread.
You can also make a double direction thread - milling it out in one direction, then reversing feed/spindle direction and milling a left hand thread over it. Or using an indexing plate to make a spline with almost no leadout like a staggertooth cutter would leave. Or something really crazy like offsetting the live tooling above the work and at an angle on the compound to make really weird looking threads or decorative finishes or compound angles like fins on an impeller.
Nice little experiment Stefan. It would be an easy task to use an ER 16 collet chuck with a long shank (flea bay is full of them) and toothed belt drive it with a low kv BLDC motor for more torque and larger tools. There must be countless cordless drills out there with a blown speed control. No problem just use an RC speed controller and pulse generator. The router motor definitely has its limitations with it's extreme speed making HSS tooling all but unusable except for very small tools.
I made mine using a high speed spindle available on eBay from some Chinese manufacturer with a VFC that came with it. An 800 watt motor. Works very well. While I’m typing I forget the ER collet size that came with it. Now that you say it’s 16, I think that’s what on mine.
Nice to see not only I abuse this scratch proof sheet... ;) Awesome project and a wonderful demonstration. There are many machinist (good ones!) that are funny, fascinating and brilliant - but I think your videos are always a treat and I look forward to these... :) Thank you!!!!
We always have minor issues with threadmills and threading in general when our comes to fit. Obviously there is a standard calculation for working out the root radius. But most of our tools are standard 0.4 rad (thread mills). This isn’t a massive deal however just means normally you’d go abit deeper if the tool allows. M36-M120 this is pretty apparent.
I have been doing milling on my lathe for a while now and the first thing you need is a spindle indexing disc and a brake acting directly on the spindle axis. I usually index the chuck by jamming the feed gear that's 1:1 to the spindle with a pin and that way I do keyways, holes, steps and I even made the 60 position axial ratchet for my Tripan toolpost using this method. Don't forget that you can use the compound to mill at an angle (eg to make an insert cutter) or put it above or below centerline using the qctp (usually to sidemill a surface that is on centerline) essentially utilizing it as a limited travel vertical milling attachement (you can't feed upwards though).
@@StefanGotteswinter The mill I work with is a very heavy to move around and setting it up is a real hassle. Being able to cut a keyway in 5 minutes is such a delight for me!
When you want to cut a long pitch like an oil groove on a centre lathe, you can switch gears around but you have to go to the trouble of driving the lathe via the leadscrew. in other words, if you had a reduction unit lying about and you chain drive the leadscrew from the tailstock end it works fine.
GOOD stuff danke Stefan, I have some spare routers, plunge type, I also have a Cazenave 570 x 2000 the apron is huge, sure I can dream up something Looks like long keyways would be easy eh!!
Thank You Stefan....Excellent & something I will be doing. I plan to use this technique on hard wood containers with a threaded lid. Just for the fun of it....TM
Using that endmill on your lathe, you can hog out some serious material!! Awesome work grinding those 4 flute mills! Getting the geometry right seems like a lot of fun.
you are a master and I think in due time your videos will get the recognition and views they deserve, But kee it up please, youve genuinely have helped me excel at the shop i work at