Myford 7 with 1466 clutch unit

[Richard Parker 2Participant @richardparker2]

Hi
I have a Myford ML7 lathe with a 1466 clutch unit fitted, this worked very well until two weeks ago. Mechanically actuating the clutch lever does work the clutch as required, a strip down shows the lining are in good condition however no adjustment will disengage the drive to the head stock. In short the only way to stop the chuck is to turn off the motor electrically. Could anyone please advise a solution to the problem. Thanks in advance Richard

[Richard Parker 2Participant @richardparker2]

wont disengage drive

[davebParticipant @daveb17630]

There is a small pin that engages with the operating arm in the clutch boss, it sounds as though it may have fallen out.

[Brian WoodParticipant @brianwood45127]

Hello Richard,

Welcome to the forum, I hope someone can help you. There are two versions of the clutch, I don't know which is which from the 1466 identifier

Is the clutch the older version with the expanding metal horseshoe shaped piece inside the pulley cluster on the spindle, or the more recent cone clutch type that is drawn into the two stage countershaft pulley driven by the motor? From your description it sounds as though a spring or link has failed

Regards

Brian

Edited By Brian Wood on 28/01/2016 17:55:55

Edited By Brian Wood on 28/01/2016 17:57:19

[Richard Parker 2Participant @richardparker2]

Hi Guys

Thanks for replies

The clutch unit is the expanding brake shoes type, all parts are there and it works as a unit in its own right, however with clearance on the shoes, (non drive) I have permanent drive and stop the chuck by switching off the motor.

Regards

Richard

[Swarf, Mostly!Participant @swarfmostly]

Hi there, Richard and Brian,

Brian, with respect, I think you're describing the clutches on the Super Seven, Richard asked about the 1466 clutch on the ML7.

Richard, when the clutch is disengaged, the 'outer' member of the clutch, which is combined with the belt pulley (item 5 on the exploded diagram, page P) , should run freely on the inner part which is keyed to the counter-shaft (item 38). Yours isn't running freely so my best guess is that there's been a lubrication crisis and the two parts have seized!

I suggest that you try injecting some penetrating oil (e.g. Plus-Gas if you can find it) and try to rotate the big pulley while holding the counter-shaft cone pulley – put the second belt on to the largest section of the counter-shaft cone pulley and grip the two spans of the belt together to act as a strap wrench.

If that fails, it sounds as though you'll need to dismantle.

Do you have the ML7 user handbook? I fear that the clutch end of the exploded diagram on page P isn't as clear as one might hope!!

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 28/01/2016 21:42:16

[Simon Williams 3Participant @simonwilliams3]

I seem to remember that I had something similar happen to mine, and traced it to wear on (off) the outer surface of the clutch shoe. I found that the clutch shoe had got worn enough for it to be eccentric, and that I could either adjust the clutch to drive all the time, or not at all, but not both. I fiddled with it for ages before deciding to take a lick off the OD of the horseshoe so it was round and concentric with the countershaft, but then it was undersize and I didn't like to force the expander wedge that far. The horseshoe shaped bit is cast iron, so there's only so far it will bend before it goes ping. I bored out the corresponding bore in the side of the driven pulley, and lined it with a bit of bronze to bring it back to size. It's been working fine since.

I'd planned to make a replacement horseshoe out of Tufnol, but I've never been back to this project.

I seem to remember some complicated dance to be able to machine the bits of the clutch on the same lathe that I'd taken it off, just using it stop start. Maybe I made a dummy drive clutch, but I don't remember the details.

HTH, rgds Simon

[RobboParticipant @robbo]

These pics from my album might help

[Richard Parker 2Participant @richardparker2]

Thanks to those guys who have helped with this problem, Swarf,Daveb,Brian,Simon and Robbo the problem now solved clutch unit is fine.

The magic faries have pointed out that the cast iron drive pully had siezed on the counter shaft. No excuse for lack of maintenance other than a second hand machine of recent purchase

Thanks once again to all

[Swarf, Mostly!Participant @swarfmostly]

Hey, who are you calling a 'fairy'?!?!

It's bad enough that no-one responded to my implied question regarding the availability (or not) of Plus-Gas!!

Best regards,

Swarf, Mostly!

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Swarf, Mostly! on 29/01/2016 19:41:53:

It's bad enough that no-one responded to my implied question regarding the availability (or not) of Plus-Gas!!

.

Didn't realise that you were looking to buy … Just thought your can must have gone AWOL

It's widely available … For example: **LINK**

MichaelG.

[Simon Williams 3Participant @simonwilliams3]

Just for my curiosity, are there needle roller bearings up the centre of the pulley or are they plain bearings? It's a long long time since I had the "pleasure" of taking it all apart.

Rgds

Simon

[Swarf, Mostly!Participant @swarfmostly]

Posted by Michael Gilligan on 29/01/2016 20:03:46:

Posted by Swarf, Mostly! on 29/01/2016 19:41:53:

It's bad enough that no-one responded to my implied question regarding the availability (or not) of Plus-Gas!!

.

Didn't realise that you were looking to buy … Just thought your can must have gone AWOL

It's widely available … For example: **LINK**

MichaelG.

Michael,

Thank you for your post. Some time ago I sought Plus-Gas at my local 'Go Faster' shop and was told it was no longer available! The story was that this was yet another casualty of the glue-sniffers' folly, like black Bostik.

Thanks to your post, I'll try again.

Best regards,

Swarf, Mostly!

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Swarf, Mostly! on 29/01/2016 21:46:32:

Some time ago I sought Plus-Gas at my local 'Go Faster' shop and was told it was no longer available! The story was that this was yet another casualty of the glue-sniffers' folly, like black Bostik.

Thanks to your post, I'll try again.

.

Happy to help another PlusGas aficionado, Swarf

… I suspect that the 'Go Faster' shop stocks something with a better mark-up.

MichaelG.

.

If you prefer to support established tool dealers: It's also listed by Buck & Hickman

[Richard Parker 2Participant @richardparker2]

Simon

The cast iron pulley wheel has no bearing, just plain iron running on the steel mandrel. Lack of lubrication caused the seizure which has left light scoring about 0.005" deep on the mandrel which will have to be replaced at some time.

An alternative possibility may be to reduce the mandrel diameter at the affected place on the shaft and bush the pulley wheel, the center of the clutch housing would also have to be reduce/bushed to suit. Question is where does this lead and where do you stop.

Regards

Richard

[robert davies 6Participant @robertdavies6]

hI All,

I am strugglibg to remove the clutch from my ML7. It has just stopped driving so I guess an internal drive pin has come loose. I have removed the Allen grub screw that I thought secured the clutch on the drive shaft but the clutch unit will not move. Any helpappreciated

Bob

[robert davies 6Participant @robertdavies6]

panic over. There are 2 grub screws holding the clutch to the outer shaft.

Also, the problem was not in the clutch itself but the grub screws holding the pulleys onto the shaft had both come loose .

Silly me for not noticing.

The clutch shoes are a bit worn and have swarf embedded in the surface but are still able to function when cleaned of any residual grease.

Bob

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