My brother worked in a machine shop. A new-hire started his 18" lathe without removing the chuck key. The key flew across the room narrowly missing the back of the machine shop foreman's head. The foreman walked over and clocked the new-hire and called it self-defense. Knowing this experience, I still remove the springs on my chuck keys. Knowing this experience I'm DAMN careful to remove the key immediately after its use. You can't legislate against stupidity. What I have seen that I like better than the spring is a micro-switch in the motor control logic that won't start the motor or spindle unless the key is stowed correctly. Saw something similar in a private shop. Power to the shop wouldn't energize until he stowed his wedding ring on a pedestal. A tiny current detected the presence of his ring, which energized a master relay for the shop. I always enjoy your videos.
I think that the chuck key spring is a good compromise between protecting the "first time user" and actual usability; it doesn't get in your way as much as those awful plastic chuck guards do and it does the job just as well. It's also easy to remove and given the ease a spring like that will disappear in a machine shop, a cheap insulation against stupidity lawsuit.
It is best to teach the simple rule: If the key is in the chuck, your hand must be on the key. If your hand is off the key, the key is out of the chuck. If they can't manage to follow that simple rule then a bitch slap is the best response.
I'm so excited to follow the mill restoration adventure! It looks like there will be a lot of things that are very different about this restore vs the G&E. That 6-jaw is an amazing and well-deserved gift, especially considering how much you share with your audience. The new table looks like it makes getting different camera angles easier, as well as being heavy duty enough to handle nearly any work piece. While I prefer to keep my comments about the shop and work, I have to say that you are looking and sounding healthier and happier. Thank you for making every Saturday Night a special time of learning and appreciation for machines, machining, and machinists.
Great idea for KBC to promote their products on your channel. I have several You Tube Creators that I really trust and Adam you are one of them. If you say It is good then I believe it is good. Not just because they gave it to you, but because you have used it and like it. I just happen to be in the market for a new chuck and I will be looking at them. I also agree with the Polish quality. The best tool and die maker i ever had work for me was Polish. He refused anything but perfection. Rest in Peace Casmir Mrochoski.
Adam, what you are doing for the machining/mechanical engineering community is really fantastic. With the help of your channel I have picked up knowledge and technical stuff that none of my college courses ever mentioned. The passion of yours is really contagious. My father and I are restoring a clockmaker lathe for our tiny workshop. Keep up the very nice videos. Greetings from Switzerland. Benjamin.
Not only are you a hell of a fine machinist you have a heart to mach. What a great thing to give Ross the book that never dies. This is the first 6 jaw I have ever seen. What I couldn't have done over the years with something like that. It never ceases to amaze me how dirty our work can be but how hospital clean things really are, LOL. I originally thought all 6 jaws were independent. Oh well you will see far less crush with 6 vrs 4. Good to see you slowly winning with the K & T bud. You will get it.All good things in time fella !
Great video. Nice chuck, hats off to engineers and makers of it. Happy to see Polish tools around. A lot of stuff is as good or better as German, Swiss or Czech ones. Polish industry was in a lot of turmoil in 90s, but happily it is coming back. Toolmex is technically US company, but the chucks are made by Polish company, Bison Biel, or sometimes called Bison Chucks, in Białystok and Bielsk Podlaski. Toolmex is just selling them as a distributor and licensee, and have a own logo on it. Bison Biel have a long history actually (started in 1948), exporting a lot of products to Soviet Union and other Eastern Block / Warsaw Pact countries. In late 80s, they were huge exporter to all countries of the world (USA, Japan, Germany, France, Italy, UK), and by 1988 they were in fact the biggest manufacturer of work holding and chucks in the world (70% of world supply). They were one of the first Polish machine shops starting using CNC machines, in early 70s. After Poland transformation, they got finally sold to private investors in 1997. A lot of company weren't so lucky (they were not very competitive or used very old technologies), but some of them are very successful. They are no longer biggest, with a lot of production from China, Germany, and USA, but still huge. They have own foundy, casting facilities and huge manufacturing capacity too. Thanks KBC for sponsoring Adam! Awesome gift.
If you use the same pinion all the time you will get consistent results. Also tighten the chuck with clicker torque wrench will improve consistency even more. Every time you use other pinions you push the scroll plate in another direction which alters the runout. ATB, Robin
Adam, on my set-true you fully tighten the cam locks as per the instructions to mate the backing plate to the spindle. There are a pair of lines and and witness arrow to know when the cams are in the proper position. Possibly one could use a torque wrench to have better repeatability mounting the cam ring to the spindle. After that you crack loose the chuck to back plate bolts and adjust centering screws to get the test pin to run true, like you would using a 4 jaw chuck. Once it's running true then you tighten the chuck to back plate bolts from the front of the chuck. You may have to play with this a little as things can shift a little when you tighten the chuck to back plate bolts. Shouldn't have screw with the cam locks to true things up but the backplate should be mounted clocked to the spindle in the same position each time you install the chuck. When moving it between lathes you may have to readjust the set true screws, all depends on how good the cam ring to spindle registration is between each lathe. Craig
Spent a couple years in my youth working at a motor rewind ship and dude, I gotta tell ya, them guys earn their money. That job was a pain in the ass, hot baking ovens and chemical solvents that'd felt like they'd burn clean through your arm. Worked on a good few motors and was always thankful when all I had to do was pull/press bearings.
Ross sounds like a good recipient for that book. Keep up with your studies, Ross, and probably one day you will help someone out of a "jam". Not much, in life, more satisfying than that. Oh, and you are awesome too, Adam! :-)
Thanks for the Poland plug. My grandparents are from Poland. My late mothers last name was Korpita . My wife is from Peru and she kids me about being Polish, saying OK Polaki let's go, it's dinner time. PS my wife recently got her citizenship and is now an American citizen . She sure earned it, and has worked hard caring for me these past years. I doubt if I could pass that test, many nights she was up to 2:30 Am studying for the test. When I offered to help she would say, yes Ken go back to bed :-), she got 100 % on the test . Another great video and happy to see Toolmex sent you the chuck to try. Sure looks good to me, however I doubt if I could use it on my SB 9 inch lathe. Thanks for sharing this great video...Ken ...the old guy from Marina CA
Last name "Korpita". Interesting. It didn't sound too familiar, could be Polish, but that is would be a very rare name in Poland, in fact I checked, and in 2020, there was no person living in Poland with this name. It Maybe it was Kurpita (pronounced like English word Koorpita)? Still pretty rare, but there is 19 people with this name in Poland. Plus some outside of Poland of course.
Adam: I'm glad to finally learn what was causing the rapid raise to fail. When I watched you rebuild the knee, you paid so much attention to detail that I couldn't imagine a blockage in the hydro system. Anticipating some more K&T Refurb vids! (I feel kinda odd saying that, since it means you have to invest more money into the machine) Thanks for showing us the new chuck too. Always happy to see another Abom upload!
I’ve seen Stefan gotteswinter say on s scroll chuck you need to put the key in the same key hole if you are adjusting a part to get repeatability . Something indicative of a scroll chuck. He showed the difference and it was significant. Also, if you’ve ever noticed, thisoldtony tightens all the key holes when he uses a 3 jaw.
I once operated a Brown & Sharpe screw machine that always started slow but once up and running had plenty of power. This went on for years before I looked and found out the motor was wired for 440v and we were on 220v mains. One of the things your electrician probably told you (but you didn't mention in the video) is that converting the motor to low voltage is more than switching the wires. It also involves putting new heaters in the motor starter since the low voltage will be pulling more amps. That easy enough if you can find the heaters. Many of the old starters don't have replacement parts anymore and finding the heaters might be a problem. The transformer is a good alternative to having to find parts and switching wiring...
Hi I have a nearly 80-year-old 11th edition 1941 in immaculate condition even has blue colored page edges, it belonged to an RAF aircraft engineer in 1941 and I have it to pass on to my boys, its a priceless reference to any machinery professional or hobbyist. there are lots on Ebay for sale. Take care, Mac
really enjoying your vids, abom. but just two things on this one: 1. adjustable chucks like this one with separate back plate and adjusting screws always require a certain torque on the mounting screws, otherwise the adjusting action might not work the way it should. dunno if this particular chuck came with orders of instruction, if not you should contact dealer/manufacturer for further information. 2. indicating new chucks out of the box for runout should always be performed by the manufacturers intention, you def should use a pin exceeding the clamping length of the jaws in order to counter any bending action of the jaws in their respective guidances as it is very important for the repeatability when we're talking about runout close or under a thousands. just my two cents on that. btw: if you wondered what purpose a 6-jaw chuck might serve you'd be surprised the next time you'd have to machine a thin walled ring of any sort.
Rebuild/rewind motors. Good motor winder can do for you and set voltage for pretty much what ever you want. Transformers are an inefficient kludge. Best solution for long-term fix is rebuild / rewind..
Watchen you use that for the 1st time made me smile a little bit because ive used a 6 jaw for a couple of years and the easiest way to indicate the work pieces is to just loosen all the set screws in the and just tram from there.
I remember getting hired at a garage/shop that rebuilt high volume blowers made by gardner denver, brake shoes and bands, and lots of other stuff. The guys that worked there before me must have been from munchkin land because my work table and bench were about 10" to low so I welded a 10" hunk of I beam to the bottom of everything so I wouldn't cripple myself.
..Mill Motor.....and the machine input voltage...I've done a lot of machinery maintenance. Your friend David has the right idea, if the mill was originally wired for 'only' 440-480 it would be very good to get an external transformer and get your shop 208/240 hooked up. You can often find these transformers in good used condition at a motor/circuit breaker shop. The motor shouldn't be too hard to repair...some cleaning, couple bearings...and you are certainly capable of any shaft repairs... And...if you're running the machine on 208/240, you're only getting part of the actual horsepower from any of the motors.
Great video Adam. I have got behind on your posts, playing catch up now. I think the handbook is going to a good home. I hope he gets plenty of use out of it. That looks like a really nice chuck. Really nice of KBC to gift it to your shop.
When you tighten the adjust screws in the chuck, you are pushing the chuck away from the backplate and away from the center. It works the opposite way from a 4 jaws chuck.
I'd bet Tom L. would have some pointers on the six jaw's quirks. Very nice acquisition. Three tenths isn't too shabby! Looking forward to the K&T repairs. Thanks for the video.
I also had a total nightmare of a time getting a 6 jaw scroll chuck, a Bison, dialed in the first time. They can be made to run dead-on, though, and it's very helpful to not worry about buckling or crushing thinner tubes. Worth every penny, to me, and I use it almost as much as my 4 jaw independent.
Good looking chuck, it’s a good way to get some advertising I had never heard of them... the shop is looking good, I’m happy you’re getting there, that’s an amazing amount of time and work to pull it off... congratulations...
Brake cleaner is excellent for cleaning that cosmoline off, evaporates and leaves no residue, dont know if its accepted for machine parts and tooling or not. That chuck is a sweet peice of tooling, what a great gift for your shop.
I learned how to indicate in on a 6 jaw last term in school and it was a lot of fun learning. I enjoyed watching you troubleshoot all the why's and how come's when you go the wrong direction. Thanks for the great video's.
$1500 chuck that they dont have in stock. That is surprising because you would think they would be ready for people to order them after the great advertisement that your channel provides. I wish I had one but it is a big investment.
Wow, that is some noise! Sorry I just caught up to this Adam, keep us posted. I am happy you are taking care of the ole girl. Remember, the big'uns need love too!
Adam, Indicating from the chucked true pin is better technique than indicating the chuck OD. In today's manufacturing world you can expect for the OD to be true to the work holding jaw ID, but you don't machine with the chuck OD. My experience is mostly Kitagawa, SMW, and I would only rely on chuck OD when I had no other option. Chuck OD provides more surface area and a brand new chuck has suffered no dinging damage. I confirm my chuck OD readings to indicating from a decent standard in the jaws. Others have already explained well why your adjustments were backwards from what you expected. I haven't seen your model K&T since we scrapped ours after the great Missouri River flood of 1993. I spent a lot of time troubleshooting and repairing our K&T when I was cutting my teeth doing machine tool repair. We only used our machine for horizontal work, replying on Bridgeport Series II for vertical work in that class size. The use of the hydraulic flow control by K&T was unique to my experience. Over the years our manual machines almost 100% phased out to CNC. I have all manual machines in my home hobby shop. Good luck on your repairs. Your solution doesn't match your condition description, but this only shows that you are a machinist and not an electrician. I would love to be close enough to help you troubleshoot and make the repairs. You are decades ahead of me in machining skills. I enjoy your videos. I have a partially restored LeBlond lathe begging for space in my overcrowded shop. This will be a significant jump up from my Craftsman/Atlas lathe.
Adam, Normally every 240/400 V motor CAN be rewired from 400 V to 240V The difference is that one is a Delta configuration, the other is star. In a 240 V config it WILL draw more current (obviously) It would surprise me, if the motor needs internal changes for that. (never had that happen in a 30 year career as an EE) Of course American standard wiring for motors can be different to European style. Though I doubt it. So basically you wouldn't need a transformer, just the proper config for your motors. Three phase motors are though SOB's and rarely 'go broke'. Maybe the can use some love and a new set of bearings now and again. If you want further info or have other questions, just email me. Paddy
You will love using that beautiful 6 jaw. When you can quickly swap out parts without having to redial, it changes the way you can work speeding up the process for identical parts. With a bit more fiddling you should be able to get repeatability with only tightening at "0" location.
Nice chuck. After I got my General 12 x 33 started to get tooling from KBC. Great bunch of people in the Vancouver Canada Branch , always willing to give advice on which tools will work best for what I am doing. Recently bought a General mill from them and have no complaints about their service. Keep up the great videos.
That chuck is beautiful, It's also very useful to see how to marry a chuck up the the headstock properly. I already worked out that is something vital and worked out a way of doing it but with at my level of experience it's great to see other ways that work better, heck of a steep learning curve but damn I love it
Odd timing, just came in from the shop cleaning /maintenance day and one of the items was to check and reset my Buck chuck adjust-a-true on my Monarch 10ee and turn you on and you are doing it...lol
Adam, on my 307 S12, K&T extended the leads for the knee motor all way out to the electrical connection box behind the rapids lever. That box is open in the video, so the motor leads obviously aren't there on your mill. However, if you ever have to do any work in the knee again, you might consider extending the leads out to there regardless of what you do with the transformer now.
Ran a Toolmex lathe in a previous job. It was a nice machine, aside from my boss messing up the three-jaw chuck by overtightening it and likely warping the scroll plate. I kept having to take it off and put the four-jaw on, and I don't think he could indicate to save his life...or he was just too lazy to bother.
Following your K&T ever since you brought it home from James Kilroy's shop, has been a delightful adventure. Maybe share a little of the history of its past and where it originally lived?
The inrush current of a transformer with a 240v primary and 480v secondary will be huge. You will have problems with the primary over current device (breaker) tripping open on power up. You will not want to leave the transformer on all the time. It will generate heat and add utility cost. Fuses with a longer time delay will help with a larger over current device at the breaker panel. I hope your guy is correct that the knee motor is a three lead single voltage motor. Changing a nine lead motor from 480 to 240 is easy. I would definitely use a smaller transformer for the knee motor if the main motor is nine lead. After 30 years of industrial motor control. Installation and troubleshooting I still have not seen it all, but starting your main motor from a transformer would not be my first choice. Check with Stan I bet he says the same thing.
Adam, I have a 4"-6 jaw Buck chuck I bought over 30 years ago. It adjusts exactly as your 6 jaw . I use it on KO Lee universal grinder. Buck guaranteed to repeat with in .0005" when chucking on the same diameter. If you never have used one that adjusts such as ,you need to stop and think . Unlike a 4 jaw the adjusting screws push the chuck and the work up not down. Mine will offset as much as .030". I have done some very close work on mine. Sometimes with in .0001". Hope you have as good luck with yours.
Whatever you do this is gonna make a big difference btw. Running at half voltage means the motor only had 1/4 of the power it should. Unless I'm forgetting some quirk of 3 phases power.
I think feeding both motors at the same voltage is a good move. It has been my experience that the main motor running when the front feed motor is in use will act some what as a generator. you may see this when you get the transformer in and supplying 440 3 ph Thanks
Another great video Adam! Congrats on the 6 jaw chuck amigo. I love my 6 and 8 inch jaw chucks. They are great for thin wall materials. Just wanted to say, which you probably knew already, that the transformer input, or primary side current will be around twice of what's drawing on the 440 V secondary side. If the motor running current at 440 V is say 20 amps, the current on the primary side or coming from the electrical panel, will be close to 40 amps. Just wanted to give you a head's up amigo. Hopefully you won't need a dedicated circuit with a bigger breaker. You're lucky to have 3 phase service to your place! Good luck with the K&T upgrade.
Hi Adam, it might have been a good thing to point out to viewers that each individual jaw canb e unbolted and turned round if holding odd shaped items.
When you tighten the set screws to adjust the chuck, you are pushing against the shoulder of the backing plate which pulls the chuck body away from it. This is why you had tighten the lows instead of the highs. As a cnc machinist, I run into a similar situation with adjusting probe tip runout.
I watched this video regarding the motor bearings' wear. Friend of mine has a Harrison lathe with a similar problem - but a lot noisier, when I inspected the motor- the bearings had about twice the movement of your mill motor. Not surprising that it was noisy . Stripped the motor down, the drive shaft had worn about 20 thou and thrust side about 70 thou. A replacement motor I feel- just too much damage thanks for your channel, learnt a lot from you. pg Scotland
20:22 I remember my machine shop teacher in high school in the early 1960s that we should tighten all the pinions because of the internal tollerances inherit in the scroll.
When power is removed from that motor, it should be virtually silent and spin down would probably be 1 min+. I want to hear the rebuilt motor. Please redo this demo after the rebuild. :-) Great work Adam.
Hey Adam, about the Motors the best thing is to replace them both. Maybe rewind them, witch is kinda that same thing as replacing them. Using a transformer would increace the power consumtion a lot, IT would need to be big enough also, actualy bigger. Lets say You have an 8-10 kilowatts motor and a 2-3 kw for the knee, so 10-13 kw You would need a 15-20 kw transformer, and that is huge. Best thing to do is to take them to rewinding center and have both motors checked and serviced and modified for your power source. All the best!
that is some sexy chunk of tooling. stefan did a video when he got his 6 jaw, had good repeatability by indicating on and only using the 0 marked pinion.
Adam. With regard to the voltage problem as you have to repair the main motor set that to delta (low voltage ) ie 220vac then just get a transformer for the knee motor should be cheaper than a rewind ,going to a rewind for a different voltage can cause problems due to the copper iron ratio and getting the coils in the slots (due to inc. wire size ) that’s my penny’s worth I did armature and stator winding during my time ( full five year apprenticeship) from small hand grinders ( 400 hz) to 3000hp . I bet that motor has a damaged or loose bearing back plate that’s done in the seats as well , it did not float running light because the flux was holding it in the correct position ,some old time sleeve bearing motors had end float but pulled them selves into the normal position and ran fine
I was taught to tighten a Jacobs chuck using every position. Told that it "evens the forces" of the parts under stress. I didn't really question it, but it seems to make sense for scroll chucks too.
Usually one of the keyholes is marked, this is the one that was used when grinding the jaws in the factory, so you'll get the most accuracy when tightening the chuck with that one. You can use all of them, but the marked one is to be used last.
Nice Lookin' Chuck and Face Plate.. For what it may be worth.... AND.... if it were my Chuck, I'd apply "Witness Marks" to the Face Plate and Chuck, so if the Chuck and Face Plate was to be separated, they could always be assembled in the identical BOLT-HOLE CIRCLE.. Do that with TWO center punch "Witness Marks" .. One on each piece..
For those that want The Machinery's Handbook as a reference and not as a collectible here is a PDF of the 27th edition library.uc.edu.kh/userfiles/pdf/19.Machinery's%20handbook.pdf
Good choice on the Machinery Handbook. As far as the recipient looking up to you, I want to remind you that you are "channeling" three generations of machine shop workers when you work. Your Grandfather, Dad and yourself. They would be proud of you. With that very nice 6 jaw chuck, did you put a mark or line it up a certain way so it always goes in the same way? And best of all, it looks like there is less of you, Congrats. Jeff
Relating to the book - each book has something new in it or different from the last. I have an old number 16 (Dad and I) and a large print number 25 and the PDF of 26 or 27.
I feel it's important that you acknowledge the purpose of the spring. It's to prevent a safety concern when a chuck key is left in chuck and the machine is accidentally started. The key will not stay in the chuck with the spring on the chuck key. How ever I do agree with you it is very agrivating to use because you have to constintantly push down when tightening or loosening the jaws.
A far better way to avoid this risk is to make a spring loaded hanger for whichever chuck key is in use, which incorporates a microswitch which cuts control power to the drive motor relay unless the key is hung up.
@@Gottenhimfella I have even a better way, When I went through machine school in the Navy back in 1980, the instructor, a really salty old Chief, when he saw someone even begin to lift their hand off the chuck key while still in the chuck would throw whatever was in his hand, or whatever was in grabbing distance. If you were lucky enough to dodge the object there were many many pushups done in front of your lathe, 40+ years later the second I touch that key I still kinda look around for that Chief, best safety device I could ever imagine!
I have a Polish friend who is a machinist for Air Canada / Bombardier in Montreal, CAN. Maybe something genetic ? Very interesting shop, you can make almost anything imaginable.
Even though it is a "3 Jaw" style chuck, each adjusting 'hole needs to be nipped up to get maximum grip and best run-out (I think this gets all mating surfaces touching) ... this applies to 6 jaw as well, and should give an even better fit, as I think you just have done (20:40)
Thanks for video and discussions below. Most of my questions were answered. I currently have a D1-5 head and wonder if a 10 inch would work, as I have an 8 inch at present. Keep up the SNS and you do some great work with explanations.
Couldn't help to wonder if applying consistent preload to the 3 Allen head cap screws would make a difference since we are talking tenths here? Looks to be a nice chuck.
A transformer should not cost $500. All you need are three 110/220 transformers, one each for each phase. Simple wiring too. Otherwise Buck/boost transformers should fix the problem. Last time I had to do such conversion, MSC had the transformers. They are expensive, though. E-bay is your friend. Keep up the good work.
Used transformers are widely available. Check with places that tear down 15-20 year old CNC woodworking machines. Put a switch before the transformer so it isn't always drawing power. Even when a transformer is not powering the machine but is live it will dissipate energy as heat. My shop has 208V 3 phase coming in but have several transformers to provide 400 V for European machines and 460 V transformers for domestic machines. I'm surprised that the motors will run on 230V, without kicking the overloads on the contactors from trying to draw too many amps, the motors will likely run too hot if used for very long on 230V.
Hey Adam, If the 7.5hp can be wired for 220v or 440v then the other motor should be able to be rewired as well, it would not make sense for a machine company to have one motor, to have duel voltage and not the other unless it had a different control cabinet with transformers and starters when it was new. if the (knee) motor has more than 3 wires plus a ground coming out of it then you can change the voltage. If it does let me know and I can walk you through the wiring steps. Buddy
great episode. that's one handsome 6 jaw!
This Old Tony
😏I got the notification the other day saying that My Old Tony T shirt has been dispatched and is on its way.
Thanks Tony!
My brother worked in a machine shop. A new-hire started his 18" lathe without removing the chuck key. The key flew across the room narrowly missing the back of the machine shop foreman's head. The foreman walked over and clocked the new-hire and called it self-defense. Knowing this experience, I still remove the springs on my chuck keys. Knowing this experience I'm DAMN careful to remove the key immediately after its use. You can't legislate against stupidity. What I have seen that I like better than the spring is a micro-switch in the motor control logic that won't start the motor or spindle unless the key is stowed correctly.
Saw something similar in a private shop. Power to the shop wouldn't energize until he stowed his wedding ring on a pedestal. A tiny current detected the presence of his ring, which energized a master relay for the shop.
I always enjoy your videos.
I think that the chuck key spring is a good compromise between protecting the "first time user" and actual usability; it doesn't get in your way as much as those awful plastic chuck guards do and it does the job just as well. It's also easy to remove and given the ease a spring like that will disappear in a machine shop, a cheap insulation against stupidity lawsuit.
It is best to teach the simple rule: If the key is in the chuck, your hand must be on the key. If your hand is off the key, the key is out of the chuck.
If they can't manage to follow that simple rule then a bitch slap is the best response.
I'm so excited to follow the mill restoration adventure! It looks like there will be a lot of things that are very different about this restore vs the G&E. That 6-jaw is an amazing and well-deserved gift, especially considering how much you share with your audience. The new table looks like it makes getting different camera angles easier, as well as being heavy duty enough to handle nearly any work piece. While I prefer to keep my comments about the shop and work, I have to say that you are looking and sounding healthier and happier. Thank you for making every Saturday Night a special time of learning and appreciation for machines, machining, and machinists.
Great idea for KBC to promote their products on your channel. I have several You Tube Creators that I really trust and Adam you are one of them. If you say It is good then I believe it is good. Not just because they gave it to you, but because you have used it and like it. I just happen to be in the market for a new chuck and I will be looking at them. I also agree with the Polish quality. The best tool and die maker i ever had work for me was Polish. He refused anything but perfection. Rest in Peace Casmir Mrochoski.
Adam, what you are doing for the machining/mechanical engineering community is really fantastic. With the help of your channel I have picked up knowledge and technical stuff that none of my college courses ever mentioned. The passion of yours is really contagious. My father and I are restoring a clockmaker lathe for our tiny workshop. Keep up the very nice videos.
Greetings from Switzerland. Benjamin.
WOW. Greetings from Poland. It's amazing that you are using something from "my" country.
your country makes TOP notch machinist gear. be proud!
Greetings from Poland. You have huge community here. We love your shop talk series !
Ba. And from Poles outside of Poland too ;)
Not only are you a hell of a fine machinist you have a heart to mach. What a great thing to give Ross the book that never dies. This is the first 6 jaw I have ever seen. What I couldn't have done over the years with something like that. It never ceases to amaze me how dirty our work can be but how hospital clean things really are, LOL. I originally thought all 6 jaws were independent. Oh well you will see far less crush with 6 vrs 4. Good to see you slowly winning with the K & T bud. You will get it.All good things in time fella !
Great video. Nice chuck, hats off to engineers and makers of it. Happy to see Polish tools around. A lot of stuff is as good or better as German, Swiss or Czech ones. Polish industry was in a lot of turmoil in 90s, but happily it is coming back. Toolmex is technically US company, but the chucks are made by Polish company, Bison Biel, or sometimes called Bison Chucks, in Białystok and Bielsk Podlaski. Toolmex is just selling them as a distributor and licensee, and have a own logo on it. Bison Biel have a long history actually (started in 1948), exporting a lot of products to Soviet Union and other Eastern Block / Warsaw Pact countries. In late 80s, they were huge exporter to all countries of the world (USA, Japan, Germany, France, Italy, UK), and by 1988 they were in fact the biggest manufacturer of work holding and chucks in the world (70% of world supply). They were one of the first Polish machine shops starting using CNC machines, in early 70s. After Poland transformation, they got finally sold to private investors in 1997. A lot of company weren't so lucky (they were not very competitive or used very old technologies), but some of them are very successful. They are no longer biggest, with a lot of production from China, Germany, and USA, but still huge. They have own foundy, casting facilities and huge manufacturing capacity too.
Thanks KBC for sponsoring Adam! Awesome gift.
If you use the same pinion all the time you will get consistent results. Also tighten the chuck with clicker torque wrench will improve consistency even more. Every time you use other pinions you push the scroll plate in another direction which alters the runout.
ATB, Robin
your right on. I hope Abomb reads your comment.
Thanks me too
Adam, on my set-true you fully tighten the cam locks as per the instructions to mate the backing plate to the spindle. There are a pair of lines and and witness arrow to know when the cams are in the proper position. Possibly one could use a torque wrench to have better repeatability mounting the cam ring to the spindle. After that you crack loose the chuck to back plate bolts and adjust centering screws to get the test pin to run true, like you would using a 4 jaw chuck. Once it's running true then you tighten the chuck to back plate bolts from the front of the chuck. You may have to play with this a little as things can shift a little when you tighten the chuck to back plate bolts. Shouldn't have screw with the cam locks to true things up but the backplate should be mounted clocked to the spindle in the same position each time you install the chuck. When moving it between lathes you may have to readjust the set true screws, all depends on how good the cam ring to spindle registration is between each lathe.
Craig
Spent a couple years in my youth working at a motor rewind ship and dude, I gotta tell ya, them guys earn their money. That job was a pain in the ass, hot baking ovens and chemical solvents that'd felt like they'd burn clean through your arm. Worked on a good few motors and was always thankful when all I had to do was pull/press bearings.
I’ve been in a few electric motor shops and all of them seem like hard work, every day.
@@Abom79 Yar, that job drove me straight into the army and then into the IT field lol.. wouldn't trade the experience though, learned a fair bit.
Ross sounds like a good recipient for that book.
Keep up with your studies, Ross, and probably one day you will help someone out of a "jam".
Not much, in life, more satisfying than that. Oh, and you are awesome too, Adam! :-)
You have a good heart Adam. I think you picked a good owner of the book. Nice video
Thanks for the Poland plug. My grandparents are from Poland. My late mothers last name was Korpita . My wife is from Peru and she kids me about being Polish, saying OK Polaki let's go, it's dinner time. PS my wife recently got her citizenship and is now an American citizen . She sure earned it, and has worked hard caring for me these past years. I doubt if I could pass that test, many nights she was up to 2:30 Am studying for the test. When I offered to help she would say, yes Ken go back to bed :-), she got 100 % on the test . Another great video and happy to see Toolmex sent you the chuck to try. Sure looks good to me, however I doubt if I could use it on my SB 9 inch lathe. Thanks for sharing this great video...Ken ...the old guy from Marina CA
Last name "Korpita". Interesting. It didn't sound too familiar, could be Polish, but that is would be a very rare name in Poland, in fact I checked, and in 2020, there was no person living in Poland with this name. It Maybe it was Kurpita (pronounced like English word Koorpita)? Still pretty rare, but there is 19 people with this name in Poland. Plus some outside of Poland of course.
Adam: I'm glad to finally learn what was causing the rapid raise to fail. When I watched you rebuild the knee, you paid so much attention to detail that I couldn't imagine a blockage in the hydro system.
Anticipating some more K&T Refurb vids! (I feel kinda odd saying that, since it means you have to invest more money into the machine)
Thanks for showing us the new chuck too. Always happy to see another Abom upload!
I’ve seen Stefan gotteswinter say on s scroll chuck you need to put the key in the same key hole if you are adjusting a part to get repeatability . Something indicative of a scroll chuck. He showed the difference and it was significant. Also, if you’ve ever noticed, thisoldtony tightens all the key holes when he uses a 3 jaw.
Another good SNS.
I've never seen a 6 jaw chuck. Interesting.
Thanks again for all your work. Always learn something.
I once operated a Brown & Sharpe screw machine that always started slow but once up and running had plenty of power. This went on for years before I looked and found out the motor was wired for 440v and we were on 220v mains.
One of the things your electrician probably told you (but you didn't mention in the video) is that converting the motor to low voltage is more than switching the wires. It also involves putting new heaters in the motor starter since the low voltage will be pulling more amps. That easy enough if you can find the heaters. Many of the old starters don't have replacement parts anymore and finding the heaters might be a problem. The transformer is a good alternative to having to find parts and switching wiring...
Exactly! Thank you! More to the job them just swamping wires around.
Your heart is so big. Its not the handbook. Its you. Whole lotta love adam!
Hi I have a nearly 80-year-old 11th edition 1941 in immaculate condition even has blue colored page edges, it belonged to an RAF aircraft engineer in 1941 and I have it to pass on to my boys, its a priceless reference to any machinery professional or hobbyist. there are lots on Ebay for sale. Take care, Mac
6:00
Nice to hear that, greetings from Poland, Adam!
really enjoying your vids, abom. but just two things on this one:
1. adjustable chucks like this one with separate back plate and adjusting screws always require a certain torque on the mounting screws, otherwise the adjusting action might not work the way it should. dunno if this particular chuck came with orders of instruction, if not you should contact dealer/manufacturer for further information.
2. indicating new chucks out of the box for runout should always be performed by the manufacturers intention, you def should use a pin exceeding the clamping length of the jaws in order to counter any bending action of the jaws in their respective guidances as it is very important for the repeatability when we're talking about runout close or under a thousands.
just my two cents on that.
btw: if you wondered what purpose a 6-jaw chuck might serve you'd be surprised the next time you'd have to machine a thin walled ring of any sort.
Rebuild/rewind motors. Good motor winder can do for you and set voltage for pretty much what ever you want. Transformers are an inefficient kludge. Best solution for long-term fix is rebuild / rewind..
Watchen you use that for the 1st time made me smile a little bit because ive used a 6 jaw for a couple of years and the easiest way to indicate the work pieces is to just loosen all the set screws in the and just tram from there.
I remember getting hired at a garage/shop that rebuilt high volume blowers made by gardner denver, brake shoes and bands, and lots of other stuff. The guys that worked there before me must have been from munchkin land because my work table and bench were about 10" to low so I welded a 10" hunk of I beam to the bottom of everything so I wouldn't cripple myself.
..Mill Motor.....and the machine input voltage...I've done a lot of machinery maintenance. Your friend David has the right idea, if the mill was originally wired for 'only' 440-480 it would be very good to get an external transformer and get your shop 208/240 hooked up. You can often find these transformers in good used condition at a motor/circuit breaker shop. The motor shouldn't be too hard to repair...some cleaning, couple bearings...and you are certainly capable of any shaft repairs...
And...if you're running the machine on 208/240, you're only getting part of the actual horsepower from any of the motors.
Great video Adam. I have got behind on your posts, playing catch up now.
I think the handbook is going to a good home. I hope he gets plenty of use out of it.
That looks like a really nice chuck. Really nice of KBC to gift it to your shop.
When you tighten the adjust screws in the chuck, you are pushing the chuck away from the backplate and away from the center. It works the opposite way from a 4 jaws chuck.
I'd bet Tom L. would have some pointers on the six jaw's quirks. Very nice acquisition. Three tenths isn't too shabby! Looking forward to the K&T repairs. Thanks for the video.
A bit of Stefan Gottewinter creeping in there, “ Not too shabby”
I also had a total nightmare of a time getting a 6 jaw scroll chuck, a Bison, dialed in the first time. They can be made to run dead-on, though, and it's very helpful to not worry about buckling or crushing thinner tubes. Worth every penny, to me, and I use it almost as much as my 4 jaw independent.
Enjoy you showing us how Chuck was changed out and lined up. And Sharon the future work on the mill looking forward to the final results.
Wow. That 6 jaw chuck was so sexy. Thanks KB tools for letting Abom mount it up. As an old man, I haven't felt this way in a number of years. Wow.
Your so fortunate to have these machines, I wish I had half the shop you do, your very skilled in your craft.
That chuck is BEAUTIFUL. It’s a work of art.
glad that You like your new tool, greetings from Poland
Good looking chuck, it’s a good way to get some advertising I had never heard of them... the shop is looking good, I’m happy you’re getting there, that’s an amazing amount of time and work to pull it off... congratulations...
2 grand tool plus the back plate. But man they got way more than that in exposure. Good advertising value for sure
Brake cleaner is excellent for cleaning that cosmoline off, evaporates and leaves no residue, dont know if its accepted for machine parts and tooling or not. That chuck is a sweet peice of tooling, what a great gift for your shop.
I learned how to indicate in on a 6 jaw last term in school and it was a lot of fun learning. I enjoyed watching you troubleshoot all the why's and how come's when you go the wrong direction. Thanks for the great video's.
$1500 chuck that they dont have in stock. That is surprising because you would think they would be ready for people to order them after the great advertisement that your channel provides. I wish I had one but it is a big investment.
Wow, that is some noise! Sorry I just caught up to this Adam, keep us posted. I am happy you are taking care of the ole girl. Remember, the big'uns need love too!
Every time I see those blue chips coming off the carbide I remember the ones that went down the front of my shirt!
Same as me....and the one that fell in my friends hair!
Adam,
Indicating from the chucked true pin is better technique than indicating the chuck OD. In today's manufacturing world you can expect for the OD to be true to the work holding jaw ID, but you don't machine with the chuck OD. My experience is mostly Kitagawa, SMW, and I would only rely on chuck OD when I had no other option. Chuck OD provides more surface area and a brand new chuck has suffered no dinging damage. I confirm my chuck OD readings to indicating from a decent standard in the jaws.
Others have already explained well why your adjustments were backwards from what you expected.
I haven't seen your model K&T since we scrapped ours after the great Missouri River flood of 1993. I spent a lot of time troubleshooting and repairing our K&T when I was cutting my teeth doing machine tool repair. We only used our machine for horizontal work, replying on Bridgeport Series II for vertical work in that class size. The use of the hydraulic flow control by K&T was unique to my experience. Over the years our manual machines almost 100% phased out to CNC. I have all manual machines in my home hobby shop. Good luck on your repairs. Your solution doesn't match your condition description, but this only shows that you are a machinist and not an electrician. I would love to be close enough to help you troubleshoot and make the repairs. You are decades ahead of me in machining skills. I enjoy your videos. I have a partially restored LeBlond lathe begging for space in my overcrowded shop. This will be a significant jump up from my Craftsman/Atlas lathe.
Adam,
Normally every 240/400 V motor CAN be rewired from 400 V to 240V
The difference is that one is a Delta configuration, the other is star.
In a 240 V config it WILL draw more current (obviously) It would surprise me, if the motor needs internal changes for that. (never had that happen in a 30 year career as an EE)
Of course American standard wiring for motors can be different to European style. Though I doubt it.
So basically you wouldn't need a transformer, just the proper config for your motors.
Three phase motors are though SOB's and rarely 'go broke'. Maybe the can use some love and a new set of bearings now and again.
If you want further info or have other questions, just email me.
Paddy
Nice to see that 6 jaw chuck :) and greetings from Poland :)
You will love using that beautiful 6 jaw. When you can quickly swap out parts without having to redial, it changes the way you can work speeding up the process for identical parts. With a bit more fiddling you should be able to get repeatability with only tightening at "0" location.
theslimeylimey ggv
Every time I see the Setco commercial it brings tears to my eyes. (Of Joy).
Seeing that indicator sit dead on zero, that's good stuff.
Nice chuck. After I got my General 12 x 33 started to get tooling from KBC. Great bunch of people in the Vancouver Canada Branch , always willing to give advice on which tools will work best for what I am doing. Recently bought a General mill from them and have no complaints about their service. Keep up the great videos.
Great choice for the machinery’s handbook Adam!
That chuck is beautiful,
It's also very useful to see how to marry a chuck up the the headstock properly. I already worked out that is something vital and worked out a way of doing it but with at my level of experience it's great to see other ways that work better, heck of a steep learning curve but damn I love it
Odd timing, just came in from the shop cleaning /maintenance day and one of the items was to check and reset my Buck chuck adjust-a-true on my Monarch 10ee and turn you on and you are doing it...lol
Adam, on my 307 S12, K&T extended the leads for the knee motor all way out to the electrical connection box behind the rapids lever. That box is open in the video, so the motor leads obviously aren't there on your mill. However, if you ever have to do any work in the knee again, you might consider extending the leads out to there regardless of what you do with the transformer now.
Ran a Toolmex lathe in a previous job. It was a nice machine, aside from my boss messing up the three-jaw chuck by overtightening it and likely warping the scroll plate. I kept having to take it off and put the four-jaw on, and I don't think he could indicate to save his life...or he was just too lazy to bother.
The adjustments are backwards compared to a 4J chuck because when you tighten a screw, it pushes the chuck towards you, not away.
Since he got the chuck within a few tenths fairly quickly, I suspect he figured that out...
Following your K&T ever since you brought it home from James Kilroy's shop, has been a delightful adventure. Maybe share a little of the history of its past and where it originally lived?
The inrush current of a transformer with a 240v primary and 480v secondary will be huge. You will have problems with the primary over current device (breaker) tripping open on power up. You will not want to leave the transformer on all the time. It will generate heat and add utility cost. Fuses with a longer time delay will help with a larger over current device at the breaker panel. I hope your guy is correct that the knee motor is a three lead single voltage motor. Changing a nine lead motor from 480 to 240 is easy. I would definitely use a smaller transformer for the knee motor if the main motor is nine lead. After 30 years of industrial motor control. Installation and troubleshooting I still have not seen it all, but starting your main motor from a transformer would not be my first choice. Check with Stan I bet he says the same thing.
you know he have 3 phase going to his shop
David Howard , yes I know he has three phase. I do not know if it is 240/ 120 Delta or 120/ 208 wye.
gotcha man i though i point it out there incase it make a differnt, Thanks for info tho have a nice day man
Adam, I have a 4"-6 jaw Buck chuck I bought over
30 years ago. It adjusts exactly as your 6 jaw . I
use it on KO Lee universal grinder. Buck
guaranteed to repeat with in .0005" when chucking on the same
diameter. If you never have used one that adjusts such as ,you
need to stop and think .
Unlike a 4 jaw the adjusting screws push
the chuck and the work
up not down. Mine will
offset as much as .030".
I have done some very
close work on mine. Sometimes with in .0001". Hope you have
as good luck with yours.
That chuck gift is incredible! Too bad they didn't give you a d1-11 one. :-) lol I am sure you will have that mill in top shape soon.
Well if the Polish tooling is at all similar to the Polish, I'm sure that chuck will work overtime...
Whatever you do this is gonna make a big difference btw. Running at half voltage means the motor only had 1/4 of the power it should. Unless I'm forgetting some quirk of 3 phases power.
I think feeding both motors at the same voltage is a good move.
It has been my experience that the main motor running when the front feed motor is in use will act some what as a generator.
you may see this when you get the transformer in and supplying 440 3 ph
Thanks
Another great video Adam! Congrats on the 6 jaw chuck amigo. I love my 6 and 8 inch jaw chucks. They are great for thin wall materials. Just wanted to say, which you probably knew already, that the transformer input, or primary side current will be around twice of what's drawing on the 440 V secondary side. If the motor running current at 440 V is say 20 amps, the current on the primary side or coming from the electrical panel, will be close to 40 amps. Just wanted to give you a head's up amigo. Hopefully you won't need a dedicated circuit with a bigger breaker. You're lucky to have 3 phase service to your place! Good luck with the K&T upgrade.
Hi Adam, it might have been a good thing to point out to viewers that each individual jaw canb e unbolted and turned round if holding odd shaped items.
Looking forward to motor rebuild. I have done them in the past on old machines and it’s a satisfying job. Good luck.
When you tighten the set screws to adjust the chuck, you are pushing against the shoulder of the backing plate which pulls the chuck body away from it. This is why you had tighten the lows instead of the highs. As a cnc machinist, I run into a similar situation with adjusting probe tip runout.
I watched this video regarding the motor bearings' wear. Friend of mine has a Harrison lathe with a similar problem - but a lot noisier, when I inspected the motor- the bearings had about twice the movement of your mill motor. Not surprising that it was noisy . Stripped the motor down, the drive shaft had worn about 20 thou and thrust side about 70 thou. A replacement motor I feel- just too much damage
thanks for your channel, learnt a lot from you.
pg Scotland
I knew, there is something polish around you, by the love to sausages. 😋
Wszystkiego dobrego!
20:22 I remember my machine shop teacher in high school in the early 1960s that we should tighten all the pinions because of the internal tollerances inherit in the scroll.
one reason you had a little trouble was the fact you really tightened the chuck to the backplate, enjoy the hell out of your videos, keep it up/
When power is removed from that motor, it should be virtually silent and spin down would probably be 1 min+.
I want to hear the rebuilt motor.
Please redo this demo after the rebuild. :-) Great work Adam.
Hey Adam, about the Motors the best thing is to replace them both. Maybe rewind them, witch is kinda that same thing as replacing them. Using a transformer would increace the power consumtion a lot, IT would need to be big enough also, actualy bigger. Lets say You have an 8-10 kilowatts motor and a 2-3 kw for the knee, so 10-13 kw You would need a 15-20 kw transformer, and that is huge. Best thing to do is to take them to rewinding center and have both motors checked and serviced and modified for your power source. All the best!
15 KVA 240/208 ..480 transformers...$200-300 here in e-bay.
that is some sexy chunk of tooling. stefan did a video when he got his 6 jaw, had good repeatability by indicating on and only using the 0 marked pinion.
Lindsay , I noticed you had only one subscriber so I doubled your count . Now we're waiting for contents
Grats to Ross, Glad you got a 6 jaw i want to see ya put it to work, kcb knew who to send it to for everybody to see keep it up man
Am old timer taught me to tighten all three equal instead of one real tight. I do that one my drill press and it makes a world of difference.
Here I am at 1;00 AM watching you video, great work.
Nice duo of videos this weekend. Great chuck and enjoyed you making the shaper bar.
I don't know what I'd do without my weekly SNS
Curl up in a ball and cry then phone the psychologist. Or, have a couple more beers. Since it's Saturday, it's a coin flip.
Adam. With regard to the voltage problem as you have to repair the main motor set that to delta (low voltage ) ie 220vac then just get a transformer for the knee motor should be cheaper than a rewind ,going to a rewind for a different voltage can cause problems due to the copper iron ratio and getting the coils in the slots (due to inc. wire size ) that’s my penny’s worth I did armature and stator winding during my time ( full five year apprenticeship) from small hand grinders ( 400 hz) to 3000hp . I bet that motor has a damaged or loose bearing back plate that’s done in the seats as well , it did not float running light because the flux was holding it in the correct position ,some old time sleeve bearing motors had end float but pulled them selves into the normal position and ran fine
I was taught to tighten a Jacobs chuck using every position. Told that it "evens the forces" of the parts under stress. I didn't really question it, but it seems to make sense for scroll chucks too.
Usually one of the keyholes is marked, this is the one that was used when grinding the jaws in the factory, so you'll get the most accuracy when tightening the chuck with that one. You can use all of them, but the marked one is to be used last.
Nice Lookin' Chuck and Face Plate.. For what it may be worth.... AND.... if it were my Chuck, I'd apply "Witness Marks" to the Face Plate and Chuck, so if the Chuck and Face Plate was to be separated, they could always be assembled in the identical BOLT-HOLE CIRCLE.. Do that with TWO center punch "Witness Marks" .. One on each piece..
For those that want The Machinery's Handbook as a reference and not as a collectible here is a PDF of the 27th edition library.uc.edu.kh/userfiles/pdf/19.Machinery's%20handbook.pdf
Good choice on the Machinery Handbook. As far as the recipient looking up to you, I want to remind you that you are "channeling" three generations of machine shop workers when you work. Your Grandfather, Dad and yourself. They would be proud of you.
With that very nice 6 jaw chuck, did you put a mark or line it up a certain way so it always goes in the same way?
And best of all, it looks like there is less of you, Congrats.
Jeff
SUPER ENJOYED .. Great share Adam , That chuck is a great gift , The K&t will be so much better with some repairs ! AWESOME..
Relating to the book - each book has something new in it or different from the last. I have an old number 16 (Dad and I) and a large print number 25 and the PDF of 26 or 27.
I feel it's important that you acknowledge the purpose of the spring. It's to prevent a safety concern when a chuck key is left in chuck and the machine is accidentally started. The key will not stay in the chuck with the spring on the chuck key. How ever I do agree with you it is very agrivating to use because you have to constintantly push down when tightening or loosening the jaws.
A far better way to avoid this risk is to make a spring loaded hanger for whichever chuck key is in use, which incorporates a microswitch which cuts control power to the drive motor relay unless the key is hung up.
@@Gottenhimfella you sir......genius!
@@Gottenhimfella I have even a better way, When I went through machine school in the Navy back in 1980, the instructor, a really salty old Chief, when he saw someone even begin to lift their hand off the chuck key while still in the chuck would throw whatever was in his hand, or whatever was in grabbing distance. If you were lucky enough to dodge the object there were many many pushups done in front of your lathe, 40+ years later the second I touch that key I still kinda look around for that Chief, best safety device I could ever imagine!
Oh my - total envy!! I'd love a 6-jaw but doubt I could ever find the funds... very nice Adam. :)
You were right, Adam. The one inch Gage Pin becomes indispensable.
I have a Polish friend who is a machinist for Air Canada / Bombardier in Montreal, CAN. Maybe something genetic ? Very interesting shop, you can make almost anything imaginable.
I have a Buck Tru Chuck. Just loosen the bolts on the face first then zero out and snug them when finished.
perfect
Even though it is a "3 Jaw" style chuck, each adjusting 'hole needs to be nipped up to get maximum grip and best run-out (I think this gets all mating surfaces touching) ... this applies to 6 jaw as well, and should give an even better fit, as I think you just have done (20:40)
Pardon my ignorance but can you elaborate on nipped up? I may just be unfamiliar with the term perhaps it's a regional thing or maybe I'm just dumb :P
Damn Adam you're looking thin! Nice!
Thanks for video and discussions below. Most of my questions were answered. I currently have a D1-5 head and wonder if a 10 inch would work, as I have an 8 inch at present. Keep up the SNS and you do some great work with explanations.
Couldn't help to wonder if applying consistent preload to the 3 Allen head cap screws would make a difference since we are talking tenths here? Looks to be a nice chuck.
If I ever need a six jaw chuck .... its KBC for me.
For whatever reason, most 6 jaw chucks seem to require that all the pinions are tightened up to correct for runout.
A transformer should not cost $500. All you need are three 110/220 transformers, one each for each phase. Simple wiring too. Otherwise Buck/boost transformers should fix the problem. Last time I had to do such conversion, MSC had the transformers. They are expensive, though. E-bay is your friend.
Keep up the good work.
Used transformers are widely available. Check with places that tear down 15-20 year old CNC woodworking machines. Put a switch before the transformer so it isn't always drawing power. Even when a transformer is not powering the machine but is live it will dissipate energy as heat. My shop has 208V 3 phase coming in but have several transformers to provide 400 V for European machines and 460 V transformers for domestic machines.
I'm surprised that the motors will run on 230V, without kicking the overloads on the contactors from trying to draw too many amps, the motors will likely run too hot if used for very long on 230V.
Hey Adam, If the 7.5hp can be wired for 220v or 440v then the other motor should be able to be rewired as well, it would not make sense for a machine company to have one motor, to have duel voltage and not the other unless it had a different control cabinet with transformers and starters when it was new. if the (knee) motor has more than 3 wires plus a ground coming out of it then you can change the voltage. If it does let me know and I can walk you through the wiring steps.
Buddy
Buddy I’ve already had two different electricians look at the wiring for me.