Clarke cl430 lathe problems

[Tim CloughParticipant @timclough91841]

Just bought a clarke cl430 lathe with the auto feed not working.The gears are turning but not the leadscrew.Seems to be somethino broken around the clutch shaft.Anyone had any experience with this Lathe? Thanks

[Tim CloughParticipant @timclough91841]

No auto feed

[John RuddParticipant @johnrudd16576]

Broken shear pin somewhere in the drivetrain?

Edited By John Rudd on 09/06/2016 14:30:31

[mechman48Participant @mechman48]

Hi Tim

The CL430 is a similar lathe to the CL500 multi I had some years ago; robust machines for the ME. The clutch is a simple dog clutch mechanism that is operated when you turn the handle that protrudes through the casting, behind the tinplate cover to the left of the coupling to the leadscrew, this may well have a drive pin come out of the actuating lever of the dog clutch; where the handle / clutch lever turns but not actuating the drive half of the clutch. if the gearbox side of the coupling is turning & not the leadscrew then the shear pin that goes through the coupling to connect to the leadscrew has broken, it needs drifting out & replacing, it is a safety feature intended for this purpose to protect the leadscrew / gears. Replace the shear pin with a brass one if you can… also check there is a key driving from the last gear on the train to the drive shaft into the clutch, no key means no physical mechanical link from the last gear to the g/box shaft. It's not uncommon for something silly to have been left of these machines.

George.

Edited By mechman48 on 09/06/2016 14:40:20

[MWParticipant @mw27036]

It's a shame i can't see this because i've owned this machine for a couple of years now and have just about seen everything that can go wrong on one. The case with mine was that the clutch or "drive bush" that slides with the lever to engage the gears broke, the hex inside the cast part had rounded off, i made a new one myself because i needed some gears from clarke spares a while ago and it was like trying to get blood out of a stone.

Basically when you turn the lever the detent pushes the groove on the side of a drive bush and connects the leadscrew to the gear train via a hex shaft and socket.

Its possible to take all of this apart if you're careful, theres a securing back plate behind the gear train it's held by a couple of hex screws and taper pins. I'd start there if suspect this is it.

IF it's not the actual drive bush thats at fault then the lever has a small detent to slide the bush, it's possible this has been knocked out or off index. You can simply dismantle the lever assembly and with a small torch see where the "ridge" or groove is that the detent is meant to fit into.

If theres anything ive mentioned that you dont understand let me know because i know it can be much more confusing to "read" about a machine issue than it is to actually see it.

Having said that, i still have a high opinion of this machine, like mechman said, very robust. Me and my buddy damn near broke our backs trying to get this machine onto a bench, me at the tail stock end and him at the head stock, luckily for me he's built like a tank!

If you want i can make you a new one if you need a new clutch part/drive bush, just PM me.

Michael W

Edited By Michael Walters on 09/06/2016 15:07:50

[Tim CloughParticipant @timclough91841]

Thanks for your comments.The clutch shaft number 15 on the parts diagram is just spinning and I think this should be driving the leadscrew.I have the assembly out of the lathe and want to remove the shaft that the clutch shaft goes in to.Do I need to remove the auto feed lever First?

[MWParticipant @mw27036]

Hi Tim,

I think you would because the detent on the lever engages with the inside of the shaft bore and could be damaged if not removed. Theres a grub screw on the boss of the handle and on the casting itself and the whole lever should come out. 

I think i remember theres a couple of grubscrews on the body of the main casting of the assembly that need to be removed, they hold the shaft assembly in place, they might be obscured by paint but after it should all come out with a little bit of encouragement, it should be quite tight.

PS. Once you get inside theres a keyway that the drive bush is meant to slide on, make sure thats still there.

Michael W

 

Edited By Michael Walters on 09/06/2016 15:27:32

Edited By Michael Walters on 09/06/2016 15:28:46

[Tim CloughParticipant @timclough91841]

The clutch shaft also has a shear pin in it, but I cannot see what use it is, as appears to do nothing.I wonder if something is Missing?

[MWParticipant @mw27036]

ah, i think i know what your problem is.

the shear pin fits between the spline housing of the final gear to the leadscrew and the clutch shaft. If these parts were not fitted together there would be no drive to the gear train, as the collar would spin round rather than carrying the force of the shaft to the gear. 

If you look at the spline housing of the last gear in the train there should be a small hole going right through it, line up these parts with the hole on the clutch shaft and stick the pin through it, problem solved! hopefully

Michael W

 

 

Edited By Michael Walters on 09/06/2016 15:42:02

[Tim CloughParticipant @timclough91841]

Hi Michael, I will have another look and report back.

[mick70Participant @mick70]

another thing to know on these lathes the gear chart in manual for screw cutting is wrong.

the chart stuck to inside of door on it is right.

[Tim CloughParticipant @timclough91841]

Just managed to have a look at the problem again.Drive pin sheared on clutch shaft.Thanks for all your comments and help.

[John RuddParticipant @johnrudd16576]

Posted by Tim Clough on 14/07/2016 16:11:32:

Just managed to have a look at the problem again.Drive pin sheared on clutch shaft.Thanks for all your comments and help.

Good to hear it was a simple fix after all…..

[MWParticipant @mw27036]

No problem, good luck!

Michael W

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