Morse taper stuck :(

[Simpo Two]

Myford ML8, 2-prong drive stuck in headstock. Normally I knock it out with a 1/4" steel rod and hammer from the outboard side, but this time despite even heavy clouts with a lump hammer, it's not budging and the rod is just bending. WD40 hasn't made any difference. Can't get too violent with it or the bearings will be damaged.

Hoping for some ideas please!

[Big Al.]

Can you get a solid heavy rod up the headstock spout and knock it out?

[Simpo Two]

Big Al. said:

Can you get a solid heavy rod up the headstock spout and knock it out?

You mean from the outboard side? (the driveshaft is hollow). That's what I'm doing. All I can find is the 1/4" rod which isn't man enough for the job. I'm worried that if I use too much force the bearings will be damaged.

[Mr Pointy]

Would heating it up help? Maybe hot air gun rather than a blowtorch.

Actually freezing would be better but harder to do.

Edited by Mr Pointy on Sunday 17th June 12:38

[motco]

This is the usual tool. Have you got/tried one?

[netherfield]

I think you need something with a bigger diameter, you're probably losing force through the thin rod springing.

Has it by any chance spun in the taper?

[Big Al.]

Simpo Two said:

You mean from the outboard side? (the driveshaft is hollow). That's what I'm doing. All I can find is the 1/4" rod which isn't man enough for the job. I'm worried that if I use too much force the bearings will be damaged.

Is 1/4" dia rod the biggest that will go through? if it isn't, then use the max rod size that will fit.

[Big Al.]

Can you post an image of your problem? that may throw some other ideas into the equation.

[Simpo Two]

Thanks guys.

Mr Pointy said:

Would heating it up help? Maybe hot air gun rather than a blowtorch.

Thought of a blowtorch a la Edd China but it's too close the bearing which is full of grease

motco said:

This is the usual tool. Have you got/tried one?]

Too short and fat to fit down the driveshaft.

I tried a masonry drill in my hammer drill thinking the vibration might drive it out. Nope.

Various other candidates were either too short or too fat to fit, but eventually I found some studding. Clearly brute force was going to be needed, so to try to take the load off the bearings I found some tube that fitted over the prong drive and against the headstock, then a chunk of wood to brace it against the tailstock. Finally after a few wallops with a lump hammer it came out!

I think the problem may be that the shank of the prong drive has a fine ridging on it, as opposed to smooth. You can just feel it when you run your fingernail across it. Is there anything I could use to help it release next time? Talc perhaps?

[spikeyhead]

If it's got ridges on it then it's always going to stick. The taper should be smooth. It would probably be easiest to bin it and buy a new one

[netherfield]

As above really

It should be smooth as a baby's bum, I had similar problem with an 3mt to 2mt adaptor in a pillar drill,except that had jammed and spun, had to throw it away and buy a new one

[motco]

The drift works like this:

[Simpo Two]

Thanks Motco, but there's no facility to use that on an ML8. Bashing it out from behind is the only way.

I've tried grinding out the ridges but no improvement. Can anyone recommend a good brand of prong drive?

[moustachebandit]

Had the same issue with my pillar drill. Chuck was immovable by normal means and was concerned about doing damage trying more aggressive methods.

The approach that worked for me was heating the shaft up with a hot air gun, and then blasting the chuck itself with with an inverted can of air duster. Once the chuck was nicely frosted a few clouts with a rubber mallet and a wooden drift got it free.

[Drumroll]

Not sure what size the Morse taper is for your lathe. You could try contacting Axminster tools or these https://snaintonwoodworking.com/?SID=4i4fsp288hq2k...

[motco]

Simpo Two said:

Thanks Motco, but there's no facility to use that on an ML8. Bashing it out from behind is the only way.

I've tried grinding out the ridges but no improvement. Can anyone recommend a good brand of prong drive?

Okay, Simpo Two. Sorry, it's not a conventional style with which I'm familiar.

[Simpo Two]

motco said:

Okay, Simpo Two. Sorry, it's not a conventional style with which I'm familiar.

No problem, I'm not sure that system existed in about 1955 when the lathe was designed!

[motco]

Simpo Two said:

motco said:

Okay, Simpo Two. Sorry, it's not a conventional style with which I'm familiar.

No problem, I'm not sure that system existed in about 1955 when the lathe was designed!

Well it did when I was briefly a toolmaking apprentice in the early 1960s! The machines in the training school were pretty old, and there was even one marked with the label 'War Finish'. Oh woe is me for I am ancient...

[Simpo Two]

Maybe the difference is that the ML8 is a woodworking lathe... Does the ML7 have this slot?

[dickymint]

Wrap some emery cloth around it for protection and use a pair of Stilsons and twist it off. I'd stake my Indentures this will work!