Help! Tailstock reassembly problem

[gerrym]

Hi all,

I'm new to this forum and hope a kind soul can help solve this annoying mystery. Apologies for the poor non technical description.
I recently bought an Apollo Woodpecker lathe (sadly without instructions), and was getting on fine, until the tailstock decided to disassemble itself.
I was trying to bore into some hard wood with a forstner bit in a chuck in the (MT2 taper) tailstock. However, the bit jammed in the workpiece, and when I pulled the tailstock back, the rotation of the bit & chuck unscrewed the taper from the (?) arbor? - the bit it should attach to, that has the handwheel at its other end.

I removed the handwheel and have extracted the "arbor"(?), which is part-threaded. It seems blindingly obvious that the taper and arbor should just screw back together - but they won't, and I've tried both directions! One way they'll screw together (by hand) a fraction of a turn and then jam, and I'm not tempted the use tools to force them together - in

the other direction they just don't 'catch'
I've attached a picture of the two pieces. So: can anyone please advise how I can fit these two pieces together?

Many thanks in advance,

Gerry

 

[CHJ]

First statement is, that should not have happened as there should be a clamping bolt located in the tailstock barrel slot.

But as it has happened, it is obvious that the clamping bolt was not located correctly.

As the barrel will not now go back into the tailstock casting make sure that the clamping bolt is fully undone and not fouling the barrel when pushed in, and then when the barrel is engaged in the tailstock make sure it is rotated so that the clamping bolt locates in the slot so that it allows fore and aft movement without letting it come completely free and the clamping bolt now prevents rotation.

I've assumed that the clamping bolt is serving both functions of preventing rotation and locking in position. On some better engineered tailstocks there is a separate anti-rotation grub screw and locking bolt/clamp. In this case make sure the anti-rotation grub screw is clear of the barrel bore whilst putting barrel back in.

Now enter the tailstock actuating screw from the rear and engage it in the rear of the barrel, you may have to juggle it about a bit to get it centered in/aligned with the barrel thread.
Wind it fully in and re-attach retaining screws at rear.

When in use only slacken off clamping screw/bolt enough to allow free movement not so far as to remove clamping bolt nose from the anti-rotation location groove.

 

[gerrym]

Hi Chas,
many thanks for the reply.

You're right that I wasn't using the tailstock clamping bolt, deliberately (but maybe wrongly - I'm a beginner) - I was winding the tailstock wheel to push the drill bit into the wood.

The problem is that these two parts simply won't screw together again. I can engage them and turn about a quarter turn, then they simply jam. This was the same when I just tried to refit the taper, and also now I've removed the other part (as in the photo).
The threads of both parts are clean, unclogged and undamaged.

Thanks for the suggestion, anyhow............ anyone else?

Regards

Gerry

 

[CHJ]

....You're right that I wasn't using the tailstock clamping bolt, deliberately (but maybe wrongly - I'm a beginner) - I was winding the tailstock wheel to push the drill bit into the wood....

Nothing wrong with that, that's normal procedure, just make sure that the clamping bolt stays engaged in anti-rotation slot to stop barrel spinning.

Regarding leadscrew thread not engaging in barrel, are you sure the very end of the leadscrew is not compressed and the end of the thread closed up?
It might be that as the barrel and leadscrew became disengaged the end of the thread was damaged as the barrel spun in the tailstock housing.

In normal use winding back the barrel allows the end of the leadscrew to push on the end of the morse taper chuck shank and release it so it should be pretty robust.

 

[Retire2004]

Hi Gerry,
This may seem a bit obvious, but most tailstock assemblies have a LEFT HAND thread. Your photo is a bit small to actually see if this is the case with yours, although you did say that the barrel unscrewed itself when the drill jammed. This suggests that it IS LEFT HAND, otherwise the tailstock would have pulled forward towards the headstock!. Try assembling the two peices again (by turning anti-clockwise to engage). If it won't engage maybe the start of the thread(s) are damaged.
Hope this helps,

Regards,
Tudor

 

[gerrym]

Chas,

on close inspection of the end of the external thread, it looks as though I have indeed managed to shear off the very end of the thread.
I've found a thread grind / repair service nearby, so hopefully they'll be open on Monday!

Thanks again for the suggestions,

Gerry