How to remove Myford ML8 tailstock barrel?

[amadeus]

Hello,

I have a very stiff tailstock for a Myford ML8 and I've been staring at the very helpful diagrams of the Myford ML8 posted by @HappyPixie.

I've removed the retaining screw, thrust ring and hand wheel, and the barrel locking lever and washer.

I'm not having much luck removing the barrel itself. Can I check:

1. Does the barrel come out of the front or the back? Given the barrel locating key I would imagine it comes out the back, unlike videos of other tailstocks I've seen?
2. Do you need to remove the padbolt first, and if so, how? The padbolt is fairly wedged and it's unclear if I need to tap it down and out or pull it up?

Many thanks,

Amadeus

 

[parvum]

Hello,

I have a very stiff tailstock for a Myford ML8 and I've been staring at the very helpful diagrams of the Myford ML8 posted by @HappyPixie.

I've removed the retaining screw, thrust ring and hand wheel, and the barrel locking lever and washer.

I'm not having much luck removing the barrel itself. Can I check:

1. Does the barrel come out of the front or the back? Given the barrel locating key I would imagine it comes out the back, unlike videos of other tailstocks I've seen?
2. Do you need to remove the padbolt first, and if so, how? The padbolt is fairly wedged and it's unclear if I need to tap it down and out or pull it up?

Many thanks,

Amadeus

Hi Amadeus, The tail stock barrel is removed from the rear, by pad bolt I assume you mean the wedge that locks th barrel when the lever is rotated. This wedge is released and removed from the casting by gently tapping it down. The barrel should then be able to be tapped rearwards ie towards the wheel end. Watch out when you reinsert the barrel as the anti rotation pin needs to be correctly aligned with the slot in the barrel before any force is used as any burrs or deformation the either the pin or the slot will interfere with smooth running of the barrel.
I hope this helps, these are very capable lathes given a bit of tlc!
Best wishes Paul

 

[parvum]

Hello,

I have a very stiff tailstock for a Myford ML8 and I've been staring at the very helpful diagrams of the Myford ML8 posted by @HappyPixie.

I've removed the retaining screw, thrust ring and hand wheel, and the barrel locking lever and washer.

I'm not having much luck removing the barrel itself. Can I check:

1. Does the barrel come out of the front or the back? Given the barrel locating key I would imagine it comes out the back, unlike videos of other tailstocks I've seen?
2. Do you need to remove the padbolt first, and if so, how? The padbolt is fairly wedged and it's unclear if I need to tap it down and out or pull it up?

Many thanks,

Amadeus

 

[parvum]

Hi again Amadeus The part securing the barrel from moving forwards or backwards is bolt with a concavity machined in the side of it that matches the diameter of the barrel. The barrel is only free to move when the slot in the bolt and the barrel are exactly aligned so tightening the lever disturbs this alignment and locks the barrel, but the blt also needs to be aligned axially as well as vertically! Thus if is stuck in the casting "twisted" it will continue to jam the barrel even when pressure from the locking lever has been released, aluminium and steel are prone to galling if there is no lubrication present.If you remove the locking lever completely and then attempt to drive the barrel rearwards the bolt should be forced to rotate into alignment. You might need to introduce some releasing fluid, 50:50 ATF and Acetone has always got me out of trouble (not drinking it) or gentle heating once all the releasing fluid has been dried off acetone ignites very easily!

 

[amadeus]

Hi again Amadeus The part securing the barrel from moving forwards or backwards is bolt with a concavity machined in the side of it that matches the diameter of the barrel. The barrel is only free to move when the slot in the bolt and the barrel are exactly aligned so tightening the lever disturbs this alignment and locks the barrel, but the blt also needs to be aligned axially as well as vertically! Thus if is stuck in the casting "twisted" it will continue to jam the barrel even when pressure from the locking lever has been released, aluminium and steel are prone to galling if there is no lubrication present.If you remove the locking lever completely and then attempt to drive the barrel rearwards the bolt should be forced to rotate into alignment. You might need to introduce some releasing fluid, 50:50 ATF and Acetone has always got me out of trouble (not drinking it) or gentle heating once all the releasing fluid has been dried off acetone ignites very easily!

Thanks Parvum.

Looking at the tailstock and the corresponding diagram:

I feel that the padbolt (bolt with concavity) can only be removed AFTER you've removed the tailstock barrel?

Either way it either had existing burrs or I've added new ones tapping at it from various angles.

I can currently get the front of the tailstock flush, and use the wheel with some welly to protude about 20mm. I'm thinking that should be sufficient to secure a piece.

If I try to continue forcing the barrel out rearwards, I will most likely make it worst and perhaps wreck the whole thing?

Amadeus

ps. how are you meant to reattach parts to the bed?! I managed to unscrew the tailstock but getting it back on is proving a #**@*!!*( task

 

[parvum]

Hi Amadeus, You are quite right, the bolt will only come right out once the barrel has been withdrawn. You may be able to get the barrel to move backwards by gently heating the tailstock casting and tapping the barrel backwards with a soft drift, to avoid damaging the mouth of the morse taper.This will enable you to inspect all the bits, for burrs and possible galling.
Fitting the tailstock is complicated by the fast thread on the nut and the weight of the lump of aluminium that matches the internal bore of the bed fighting back! I have found the only way is to ensure the threads are scrupulously clean on both bolt and nut so they run together with minimum force, run the tailstock to the end of the bed,From the open end of the bed access the bolt end with the nut, then hope your fingers do not give out before you get enough thread engaged to use a rod through the side slot,to turn the nut using the threaded holes for the locking handle.
hope this helps
Paul

 

[amadeus]

I managed to remove the tailstock barrel using a hydraulic press with a brass cylinder. There was a small amount of burring but nothing particularly obvious.

I've dressed both the barrel and the tailstock cavity, and it is still a really tight fit - I can't push it in by hand for example. I'm wondering how easy it should be to push in? I can use the hydraulic press but alignment with the barrel locating key is going to be tricky.

Any tips or suggestions?

 

[Fergie 307]

Not familiar with this particular machine but generally speaking my concerns would be firstly are both the bore and the shaft actually round. I would take some measurements with a micrometer in a number of places to check. Is it similarly tight all along, or are there tight spots. You would be surprised how easily a casting like that can be bruised and possibly ovalled slightly by being struck, dropped or whatever. Secondly It's quite possible that the shaft and housing may not be original. If someone has replaced either in the past that may be an issue. They are mass produced parts so ought theoretically to be interchangeable, however the manufacturer only needs to change the tolerance a little between different versions and you could have a problem. If you are satisfied that both parts are round, and in good condition (the end shown in your picture for example is a mess, and I'm quite sure didn't leave Myfords looking like that) and it is just a clearance issue, then Google cylinder hone. You can buy a three stone hone of the appropriate size and run that through the bore to clean it up and take it out very slighly. It should be a close fit without play, but you should certainly be able to slide it to and fro by hand.

 

[Fergie 307]

Also need to check the shaft is actually straight. Ver close tolerances on these parts so it would only need to be a tiny bit out to jam.

 

[Yorkieguy]

The barrel should move very freely in and out of the tailstock with no resistance, and when fully assembled, turning the ‘wheel’ on the tailstock to move the barrel in and out should be smooth and easy.

I think it’s unlikely that the barrel is the wrong part - I suspect that what’s happened is that as the lathe has been unused for decades, the bore of the aluminium tailstock casting in contact with the steel barrel has suffered ‘galvanic corrosion’, though admittedly the bore does look smooth from the pictures.

Aluminium in contact with steel can corrode - the extent of the corrosion will depend on environmental factors. Aluminium and steel have different electrochemical properties. Aluminium is a more anodic metal than steel, meaning it is more likely to be attacked and corrode. When these two metals come into contact, they create an electrical potential difference that can cause galvanic corrosion, which is accelerated by high moisture levels.

I dare say that the lathe may have been stored in cold damp conditions for many years. To prevent galvanic corrosion, it's important to ensure that where the metals are contact with each other, adequate protection against corrosive elements (ie, lubrication). Had the lathe been in regular use, no doubt the barrel would have been lubricated and moved in and out regularly.

At this stage, if that is the case, I suspect the only solution would be to get the bore ground so that the barrel will move freely. Maybe a DIY solution could be using a suitably sized ‘flapwheel’ on an extended shaft?

Dremel 502 9.5mm 80 Grit Flap Wheel 3.2mm shaft - 2615050232

Just my thoughts.

Some link that might be of interest about the ML8 lathe:

Myford ML8 Wood Lathe (lathes.co.uk)

Myford ML8 Wood Lathe (lathes.co.uk)

Myford ML8 Universal Woodworker and Patent Text and Pictures (lathes.co.uk)

You might wish to drop an email to lathes.co.uk to seek their advice. There's not much they don't know about lathes and I don't doubt that yours is an isolated problem.

Hope that might help.

Good luck with it.

David.

 

[amadeus]

Thanks all that's really helpful. Using a combination of:

1. Coarse and medium steel wool on both the barrel and the body
2. Needle file on the barrel locating channel on the barrel
3. File on the end which was indeed ovalled
4. Lots of oil

It is now moving in and out really smoothly, including the barrel stock.