Precision Matthews Lathe Clutch Repair

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MrPragmaticLee

4 жыл бұрын

Repairing the slip clutch on a PM-1127 Lathe

Пікірлер: 61

@TATEXPRESSINC 4 жыл бұрын

Great job on the video👍🏻

@frankherring6253 4 жыл бұрын

Interesting Lee! I was a mechanic/ technician on farm and construction equipment for forty three years and had much experience with that type of clutch. I’m sure you realize that enough spring compression needs to be maintained so the balls can come out of the groves. I would measure the depth of the groves and then the screws could then be tightened until you feel the spring reach full compression, then back your screws out the appropriate amount to provide enough clearance. You can measure the pitch on your screws to determine the amount of turns to provide the clearance. If the clutch slips at the final adjustment then you need a stronger spring. Thanks for the great videos! I enjoy watching your channel.

@kermitfrog1897 3 жыл бұрын

I have the same PM1127 lathe with the same slip clutch. The screws were backed out so that the shaft was not engaged when the machine arrived. I called PM and a tech named Michael said they had no idea how to set the clutch. Thanks to all who replied explaining how to adjust the clutch

@doug3458 4 жыл бұрын

I have the same lathe, European version, a Warco 280V. The best way I found for setting the clutch is as follows. Back off all the set screws until the power feed rod can be turned independently of the gearbox shaft. Line up the two taper pins then offset by 45 degrees. The balls will then be resting on the lands between the grooves. Tighten the set screws lightly to just bottom the springs. At this setting the clutch will too tight to protect the gear box so back off each set screw by one turn. If the lathe has been subjected to a severe enough over-travel to make the clutch slip it may have caused the balls to plough a circular groove in the gear box half of the coupling. In my case it was necessary to anneal the part, re-machine and then re-harden and temper it. That crash also bent a shaft in the gear box so it is worth getting the adjustment right and not rely on the factory setting.

@theradarguy 4 жыл бұрын

Good explanation but part where you tighten then back off doesn't make sense. I'm rebuilding an Enco 13x40 right now with the exact clutch.

@phildegruy9295 4 жыл бұрын

@@theradarguy It's a quick easy way without measuring to know what travel the spring needs to have so the balls of the clutch can actually escape the groves during an overload. You set the balls out of the groves, then lightly bottom the tension springs. Then back off the tension spring screws another full turn or so to set the tension to a safer value. Add grub screws to lock the tension screws in place so they don't back off.

@TrPrecisionMachining 4 жыл бұрын

very good video..thanks for your time

@grimpo3310 3 жыл бұрын

I bought in Europe this lathe as Bernardo Profi 700 TOP. I am just preparing it for working. So I´m trying disassembly all what I will be able to for to clean it by my best. The cross bed is away, now I´m going to take down the longitudinal bed. The surface of bad and all leading areas seems to be covered by some conservation oil, with additive of some abrasive dirt. I want to clean as much as possible and to grease it with clean lubricant. Since I´ve never done something like that before, and I am nervous from that, your video gives me a little bit of courage, I can to manage it without previous experiences. Unfortunately, I am afraid, for to take down the longitudinal bed, I have to dismount both lead screw and drive rod away, to be able to do that. I believe I have to take down drive rod + leading screw + transmission of longitudinal bed away first, before I get acces for to release longitudinal bed from base-bed definitely. This also should offer me access into that transmission, for to be able to wash it inside too.

@JimRodgersWoodturner 4 жыл бұрын

Thanks for this video. I also have a PM lathe with that same clutch. It's good to see its insides and how you adjusted it.

@RagsdaleCreek 4 жыл бұрын

I thought this was a good informative video, thanks for sharing. God bless Stay safe

@dalejones4186 4 жыл бұрын

Hi Lee. Another thing to check would be to set your carriage stop and see if it causes the couch to slip like it’s supposed to or pushes it away. Nice video. I need to go check mine now. Thanks

@howder1951 4 жыл бұрын

Nice fix Lee, IMHO I think I would replace that tape with a paint mark or a scribed line, which could be checked in a glance and be adjusted accordingly. I see some good comments from others who have experience with this type of clutch. Best method is the one you understand and can control, then it isn't a problem, cheers!

@gheumann 4 жыл бұрын

Funny. I have a PM1127 too. Clutch? Mine doesn't have a clutch - just a shear pin to protect the drive. But now I see what you have and I think that qualifies as a clutch! I had my own early growing pains with mine - a "roll pin" that pinned the carriage movement crank to the its shaft, inside the apron. Just like your clutch springs, the metallurgy of a few small parts was really poor - there was NO spring in the roll pin and it simply fell out - leaving me with no way to move the carriage. But I fixed it, and I've been using that lathe for 10 years since - it has made me a lot of money and has been 100% trouble free! Nice job documenting the clutch repair.

@robertoswalt319 4 жыл бұрын

Thanks for sharing this I'll make sure that I keep an eye out when using my lathe

@rpmunlimited397 4 жыл бұрын

I like the design of that slipper clutch. Thank for the information, my old atlas lathe may be getting a update soon

@hotratz69 4 жыл бұрын

Outstanding, I needed this video, same lathe, same problem. Will be fixed tomorrow though! Thanks for posting this.

@ctrchg Жыл бұрын

great video! Thanks.

@jantimbramble7941 4 жыл бұрын

Great video! It looks like I have the sane type of clutch on my PM 1228 lathe. No problems so far, but this will remind me to keep an eye on it.

@RockingJOffroad 4 жыл бұрын

Good fix! My lathe has a cone type clutch that uses belville washers for pressure, it has a screw adjustment and a threaded locking ring. The two cones are made of brass or bronze. The lathe maintenance manual only says the clutch was adjusted at the factory and not to adjust it! My clutch slips when taking a heavy cut especially with the cross feed. I have gone in and tightened the adjustment very slightly and it has helped some, the problem is the clutch is built into the apron and to adjust it I have to remove the lead screw, the power switching shaft and completely remove the apron. Just to make a small adjustment and reassemble everything and find out I have to do it all over!

@littlerick3 3 жыл бұрын

As a retired machine designer with 30 years experience my design philosophy is to eliminate a problem if possible (a problem eliminated is one that won't bite you later). I like the addition of the tape marker which makes it obvious if the clutch slips. In addition I would replace the set screws with Nyloc type tips. It looks like adjustment now is infrequent so the tip friction will probably "last a life time" (whether that is the lathe's or the set screw's life is unknown at this time but I expect it will quite long).

@mchiodox69 4 жыл бұрын

Excellent, my PM 1228 LB has the same thing. This will be a big help I am sure in the future

@tombellus8986 3 жыл бұрын

Thanks for the info I will check mine

@edgewr 4 жыл бұрын

Hi Lee, great information as usual, at the end of video I wondered if you had checked to make sure the slip clutch operated as expected in am overload situation. Any time I have adjusted mine in the past I always make sure it will protect my lathe as expected if I accidentally overload things. Keep up the good work, look forward to your next video.

@grahameblankley3813 4 жыл бұрын

Hi Mr Lee I had trouble with my clutch, my lathe is exactly same model but different brand name, I didn't spot the ajustment screws thank you, from Coventry UK 🇬🇧👍.

@samueltaylor4989 4 жыл бұрын

Put another grub screw behind those you have in now, it will keep them from backing out.

@CruiserMac 4 жыл бұрын

I had to fix the tailstock on my PM1440 (self induced destruction). Been waiting for the parts for ever I ordered from Quality Machine so I finally had to patch it up so I could use it, will have to take it apart if and when the parts finally arrive.

@paulpipitone8357 4 жыл бұрын

Good to know and it is a good idea to keep the tape on

@stevecanny1583 4 жыл бұрын

Nice job Lee! Might be a good application for purple Loctite, just to resist the vibration but still allow adjustment. I wondered if the balls and springs would fit in from behind if you took the set screws completely out, but you probably already thought of that :) It's hard to tell on camera, but the diameter of the wire on the new springs looked thinner than that on the old ones. Might not be a bad idea to get some OE springs from Matt whenever they come in from China, just so you have some for comparison and you might like them better. Great to see your lathe is back in action :)

@richardbradley961 4 жыл бұрын

NICE ONE, THANK YOU....LEE

@noneofabove5586 4 жыл бұрын

Thanks Lee.

@outsidescrewball 4 жыл бұрын

enjoyed...good info

@wolfitirol8347 4 жыл бұрын

That's interesting I bought a european version of the PM 1127 here in Austria .... it's called Schreiner D290V two years ago it has the clutch also and it worked perfekt in case of emergency or better idioty of the user (myself) 🤗 one thing I just saw that everything is the same no wonder , it comes from the same south corean ( or chinese im not sure) factory 👍 Thanks for sharing this content for people with similar lathes it's very interesting although I never had a problem with it ...the only broken thing in two years was one of the coals of the motor the spring which pushes it towards the stator broke, but it was easy to replace.

@turningpoint6643 4 жыл бұрын

Fwiw the 11" x 27" lathes are built in Nanjing China and there's multiple dealers using the same or different paint colors. Mine was bought from a machinery dealer in Quebec Canada a bit prior to Precision Matthews selling them. I've got the rear mounted milling head on mine and at that time there were Morse Taper or R8 tapers for the milling head and the tail stock could be ordered with either a Morse Taper 2 or 3. The bigger bore version with the MT 5 head stock taper came out shortly after I bought mine or that's another option I would have ordered. Mine also doesn't have the spring loaded clutch shown in this video either and uses mild steel shear pins.

@wolfitirol8347 4 жыл бұрын

@@turningpoint6643 thanks for the Info so you also have the spindle bore 40mm with a short taper Nr 4 spindle ...the chucks are totally overpriced here in europe so I make my own adapter plates which can be a little tricky if you want it high precision . The milling head but with morse taper would also have been an option but I had a mill otherwise I would have chosen it because it's an advantage to keep the part in the same chuck that you turn it ....for high precision parts. Last year I converted my mill to CNC with closed loop steppers 12Nm torque which do a great job for little money, better than I expected. I'm building the 4 and 5th axis at the moment because there is no fixture to buy for smaller mills and they would be expensive I guess ...that's also a bit tricky cause the table isn't that big and the height of the milling head also not...after half a year of planing I found a hopeful good solution completely made out of steel with a bought and lapped high precision spindle and tapered bearings .etc.. The lathe I wouldn't convert to CNC there's no big advantage like the mill offers and conventional turning is to much fun...even with a Chinese lathe you can make real good parts in 99percent of bad parts it's not the machines fault but the users.

@paulmanson253 4 жыл бұрын

@@wolfitirol8347 Have you considered putting together a video of that CNC conversion ? Be interesting for at least some people.

@stephengile530 4 жыл бұрын

Like your comment about trying to find parts at local stores. My think, is that the people doing the ordering for the stores have no idea how things are made and what would be needed to fix it. With the bigger stores they order by what the computer says they need to order and if it isn't in the system it doesn't exist. Few years back we had a hardware store called 'Eagle Hardware' here they had everything from horse shoe nails to table saws, Lowes bought them out and first thing they did was delete 14K SKU's.

@larryschweitzer4904 4 жыл бұрын

When I saw that referred to as a "clutch" I was thinking of something that would be engaged and disengaged in normal usage. Like what lathes use that allow the motor to continuously run. I have the PM1440HD that uses a similar device. It should only operate in the case of an overload to protect the other parts. The lead screw uses a shear pin. My lathe came with a hardened steel roll pin in place of a shear pin! The parts list was for a brass pin. I made one. Bad quality control.

@woodscreekworkshop9939 4 жыл бұрын

That clutch is good to have. Interesting your friend’s lathe doesn’t have it 🤷🏻‍♂️

@turningpoint6643 4 жыл бұрын

My 11" x 27" is slightly older than yours Lee and uses the less user friendly shear pins. If you ever have that apart again it would be nice to have a depth measurement of the V grooves so others with a bit older lathes could build there own versions of this type of clutch. Hard to tell in the video, but if there's enough thread depth to use a second set of set screws that's what I'd do to lock the first ones in place and prevent them from slowly changing there pre set adjustment and at what point that clutch releases. It's likely the factory probably uses a inch lb. or metric equivalent torque wrench to set the spring tension. There's no mention of that setting in the manual?

@grimpo3310 3 жыл бұрын

I just watched another of your video, and I´d like to ask. Do you use some "original" Quick Change Toolhoder" from your supplier, or did you ordered some other from AliExpress / Bangood / eBay? If the B is correct, what type is that? Thank you. I also see you made the holes for direct acces to transmission if you want go inside, and not to loose time by dismounting the table with symbols first. Is the uncovering of the transmission as easy as it seems like, or is there some guile? Of course its clear you have leave to drain the oil out first, so I am interested about that part after that... :)

@bobuk5722 3 жыл бұрын

Hi, this is very interesting. I have an identical but different badged lathe which does not have this over run clutch. I think it would be very easy to build one and install it. It would be particularly useful with my Clough42 Electronic Lead screw. Ask me how I know! BobUK

@backlash00 4 жыл бұрын

The Micro Stop is now an option.

@shaunadams2143 4 жыл бұрын

Hi Lee very interesting I will check my lathe to see if it is the same and keep a eye on it thanks for the heads up . Did you say the pins on clutch end were tapered ? Kind regards Shaun

@MrPragmaticLee 4 жыл бұрын

Yes, pins are tapered and can only be removed in one direction.

@ronaldcrowder404 4 жыл бұрын

I cant help but wonder if it were best to use a torch wrench . Also does the clutch engage with a lever or do you use the half nut?

@kermitfrog1897 3 жыл бұрын

The shaft with the clutch on it is the feed rod, there is a separate leadscrew for threading with a half nut. Yes there is a knob you turn to shift between feed and threading.

@xkabedaruhe2956 4 жыл бұрын

I've got pretty much exact model of the lathe except it is branded as Bernardo profi 750 LZ (Austrian company). Everything but the sticker with the name looks the same.

@tano1747 4 жыл бұрын

Do you have sufficient depth in the adjustment screw holes to add a second screw on top of the first as a male "lock nut"? If so that would be worth doing. Otherwise I would suggest to measure the depth of the screw ends below the end face of the clutch and write this down. You could check regularly as part of your maintenance cycle to monitor whether the adjustment screws are backing off.

@tano1747 4 жыл бұрын

I would also second the suggestion to check it will actually slip now when you hit your stop. Remember you want this set so it JUST has enough tension as it is a mechanical circuit breaker protecting you from stripped gears broken teeth and bent shafts inside the gearbox. Rebuilding this clutch again is cheap compared to that, (actually it is free now since you have two spare sets of springs on the shelf!!). I would set it to just handle the size cut you normally take rather than to "plenty tight" as plenty tight may be the equivalent of putting a penny in the fuse holder. And i would back it off to that BEFORE testing a crash into your stop. Just a suggestion from a mechanical engineer.... But thanks for sharing your experience. That will be very helpful to many people. Regards, Neville

@adaml52 4 жыл бұрын

Good job Lee, Had the seats for the balls, been chewed up ? At what point does the clutch slip now , at what Depth of cut ? Just out of interest :) Regards Adam.

@kermitfrog1897 3 жыл бұрын

He shows this in the video

@chrisnixon2179 4 жыл бұрын

I'm looking at this lathe or the the pm1228. Are you still happy with this lathe or if you had it to do over would you get a 1228. Thanks for the video

@kermitfrog1897 3 жыл бұрын

If the 1228 is made in Tiawan it is likely a better choice

@waltbellamy4862 4 жыл бұрын

do you know where KEN BOHN IS ?

@MaturePatriot 4 жыл бұрын

Balls and short and curly springs... what's next? Great information. Now everyone who owns a PM lathe is checking their balls.

@newlifeforvintagewatches2732 4 жыл бұрын

Harrison 300 - 500 does same clutch.

@tiredoldmechanic1791 4 жыл бұрын

At least you didn't lose your balls.

@wilkbilt 4 жыл бұрын

Have you changed your email address ?

@antoniobarrios6618 4 жыл бұрын

This Mr. Lee repair is incomplete and poorly done! The spring cannot pass DIRECTLY over the 5mm ball. Because the spring opens in diameter, you need to fit a part with a 5mm head. in diameter and a 5 mm spring inlet. by 3 mm. in diameter (as if it were the HEAD of a normal tip), so that it does not fail again. I have an exact lathe but in mm. not in inches and I know what I'm saying.

@grimpo3310 3 жыл бұрын

Thank you for the hint. So, this head is not there, You need to made some by yourself? Is there any recommendation about torque moment you have to reach, when you are setting the pressure of the screw to the spring?

@antoniobarrios6618 3 жыл бұрын

@@grimpo3310 Yes, if you have to make your head, it does not come from the origin. It may be worth a nail or point for normal wood. To adjust the torque, you go, little by little tightening the set screws until the cross slide does not slip. I see that you have understood the subject very well ... Greetings