Help! Jammed tailstock!
Andy
I'm very new to all this. I have a second hand Coronet Elf lathe. I was
trying some spindle practice at the weekend and came to use the lathe again
this am, only to find that the adjustment wheel for the tailstock (with a
revolving centre in it) no longer moves. As you will appreciate, I can move
the whole tailstock assembly, but cannot tighten up on the workpiece.
I have removed the revolving tailstock but any attempt to extend/retract the
sleeve the centre sits in does not work. There is a nut holding the
handwheel on; when I remove this, the handwheel can be unscrewed from the
threaded rod and the threaded rod can be pushed through in the direction of
the headstock. It doesn't come all the way out. I don't think I did
anything different at the weekend and am totally baffled about what to do!
Can anyone give me any guidance on a way to free this adjuster and
re-establish correct operation?
I can email pics, or post them on my website if it would help.
Any advice/guidance gratefully received.
Best regards
Andy
www.gbjkites.co.uk
(no woodturning on there, but lots of kitebuilding plans and help!)
Daz Beattie
the barrell casting on centre line of the spindle and check for a
locating grub screw, there should be something to prevent the quill
shaft rotating in use and this could be the reason that the assembly
will not come apart, not sure only guessing but must be worth a look.
--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG
Ecnerwal
> revolving centre in it) no longer moves. As you will appreciate, I can move
> the whole tailstock assembly, but cannot tighten up on the workpiece.
>
> I have removed the revolving tailstock but any attempt to extend/retract the
> sleeve the centre sits in does not work.
Sight unseen I can think of two possibilities:
1: you may have a clamp screw/lever on the ram (sleeve) you've forgotten
to undo, which is keeping it in place. This is a pretty common feature,
as the ram will tend to slide back under use without one.
2: you may at the end of travel (fully extended/retracted), and the ram
may be slightly sticky at the end of travel.
Don Evans
Did you extent the quill all the way out towards the headstock? If you did,
most tailstocks will release the quill and the handwheel will just spin. To
engage it again, push on the quill towards the tailstock, at the same time you
are applying this pressure turn the handwheel so that the threads inside can
engage again. It doesn't take a lot of pressure, assuming nothing is broken, so
don't use any mechanical devices, it should work with just hand and arm
pressure. Make sure you are turning the handwheel in the direction that would
retract the quill back into the tailstock.
Don
Andy
Thanks for the response.
The quill does not move. Its all the way in. If I turn the handwheel, the
handwheel and the 'locking nut' (?) behind it both come undone until they
come off the end of the threaded rod. When they are off, it is possible to
push the threaded rod towards the headstock so it and the quill protrude
from the tailstock, but they don't come all the way out...
When I first got the lathe, I was able to turn the handwheel until the quill
came all the way out, and replace it as you suggest, but now the bloody
thing wont move!!!
Any more suggestions gratefully received.
Kind regards
Andy
www.gbjkites.co.uk
"Don Evans" <do...@nc.rr.com> wrote in message
news:3C8790CF...@nc.rr.com...
Robert A
have. I found that there is a groove on the barrel inside the
tailstock that must be in line with the screw/handle that locks the
drive center in place. The barrel rides along this groove. When the
screw is locked down the wheel cannot turn - which is what is needed
when turning. This screw/handle must be turned to unlock the wheel -
if turned too much - on my lathe - it disengages the barrel, moving
out of the groove, and the wheel just spins. I don't know if this
will help you or not.
Can you take the entire tailstock assembly apart? Perhaps the barrel
has become wedged and must be carefully forced out. You may discover
that the threads are stripped.
Robert A.
Arch
constructed machine, I suggest that you get someone who knows Coronet
lathes to advise or help you. It's difficult to understand your problem,
and risky for you to try our suggestions. I expect that you have tried
all the 'safe' ones. This,
of course, is yet another. :-) Arch
Fortiter,
Reg Sherwin
Help is probably at hand, or to put it another way, the Cavalry are
coming.
I have been using Coronet lathes professionally since 1969.
One of my 'occasional' lathes is a Coronet Minor which I shall look at
tomorrow, although I am doing a one day course, so Saturday at the latest,
and then I'll come back to you.
I suspect that the quill is jammed by the location peg which works in
the quill slot.
And I know a man who has spares as well, so replacement parts should not
be a problem if that is what is needed.
My Minor has the same tailstock assembly as the Elf, so don't do
anything until Saturday.
Keep cool!
Reg. (U.K.)
And before anyone else asks, what IS an occasional lathe the rest of the
time?
Andy <andybe...@beveridges.fsbusiness.co.uk> wrote in message
news:a67g37$al9$1...@newsg1.svr.pol.co.uk...
Bob Pritchard
It sounds to me that the mechanism is all the way back in the position where
the center is supposed to self eject.
Put the handwheel back on and run the nut up to it. Now holding the
handwheel in place tighten the nut up to the back of the handwheel.Now turn the
handwheel counterclockwise and the center should eject.Wouldn't be a bad idea
to spray it with wd40 to begin with.
I could be way off base here but this is what happened to my old lathe when
it acted as you describe.
Don't break it. :-)
Bob, Naugatuck Ct.
http://www.outofcontrol-woodturning.com
Fdmorrison
Those are good ideas.
I did not see the original post, so am piggybacking on yours.
Further possibilities to look at:
1. The TS hand wheel should be fast to the screw that runs in the quill
(usually by key and keyway on which it slides onto the screw shaft at the
outboard end), and by a thread on the end with nut to fasten the wheel. Make
sure that the hand wheel rotates *with* the shaft to which it should be
attached.
2. On very old lathe TSs, sometimes the internal thread of the quill crumbles
(sometimes made of bronze). If it gets bad enough, the screw shaft won't
engage any longer with that ruined internal thread.
You (the original poster) should be able to determine what's going on inside
the TS by unscrewing the nut holding the hand wheel, pulling the wheel off, and
then pushing or pulling the screw shaft and quill out of the TS casting. There
may be pins or keys preventing extraction, so look for them.
Frank Morrison
Reg Sherwin
I have looked at my Coronet Minor tailstock.
The thing for you to check on are firstly that the sleeve (called a
quill or a barrel), has not rotated within the tailstock recess which it
should slide up and down in.
To do this, look along the bed bar from the headstock end and note where
the groove, or keyway is in the quill. The keyway should be on the left side
of the quill, or at 9 o'clock, as this is where it will receive the key
which is fixed into the rear of the tailstock. The key stops the quill from
rotating when it is moving in and out of the tailstock.
If it is not at 9 o'clock, come back to me for the next stage. If it is
at 9 o'clock, read on.
Now take the quill locking lever out of its hole in the top of the
tailstock and look down the threaded hole. You may even need to check on the
depth of the hole with a thin probe.
My lathe has a short length of brass rod down the hole, the purpose of
which is to reduce wear between the steel quill and the steel locking lever.
I can't remember if I put the rod in which I bought the lathe from new
nearly 20 years ago, or whether it was already fitted.
The rod sometimes becomes lodged at the bottom of the hole, due to
distortion through excessive tightness from the locking lever.
Again let me know what you find.
Now to the most likely cause of the problem.
You say that the threaded rod can be pushed through in the direction of
the headstock, but not all the way out. I assume that it will also come back
but is captive.
The rod doubles as a quill mover and also a centre extractor.
The part of the rod within the tailstock has a male thread which engages
and operates a female thread is the quill.
If the quill is stuck but the rod has more that about 1/4" (6mm) of
movement, it suggests that one or both of the threads are worn. This is a
common happening as the natural tendency of a newcomer to turning is to make
sure that everything is very tight.
Again, come back to me and we'll take it from there.
Other Coronet lathe users might be interested to know that spare parts
for redundant machines can be obtained from Derek Pyatt, (01902) 791656.
Andy <andybe...@beveridges.fsbusiness.co.uk> wrote in message
news:a67g37$al9$1...@newsg1.svr.pol.co.uk...
Andy
Many thanks to you and all the others that replied with advice, support and
guidance.
I took it all apart (mole grips x 2, soft faced hammer, socket set) and it
transpires that the 'key' that fits into the keyway on the quill had sheared
off and the little bit that would usually sit in the keyway had turned
slightly and was jamming the quill. I have no recollection of 'being
brutal' with the tailstock at all, but it has still broken. The other end
of the key (threaded bolt) was well rounded over and virtually impossible to
move so I recut a slot into it and managed to remove it with a large
screwdriver. I then cleaned everything up, filed out the marks from the
mole grips etc and put it all back together with a smidge of light (sewing
machine) oil and it all appears to work just fine! I still have no idea why
it happened, but I sure as hell have a better idea of how the tailstock
functions now!!
Just as a matter of interest, if one was to remove the threaded rod and
quill, does this give potential for a 'long boring auger' type set up??
Many thanks also for the phone contact details for Derek, I'll ring him on
Monday to see about a replacement threaded key.
As you will have gathered, I am completely new to all this, but if anyone
ever needs help with kite building, please drop me a line.
Kindest regards
Andy
www.gbjkites.co.uk
"Reg Sherwin" <reg.s...@virgin.net> wrote in message
news:I29i8.13207$Bv3.2...@news6-win.server.ntlworld.com...
Reg Sherwin
(snip) I then cleaned everything up, filed out the marks from the
> mole grips etc and put it all back together with a smidge of light (sewing
> machine) oil and it all appears to work just fine!
Andy, did you also clean up the keyway in the quill?
> Just as a matter of interest, if one was to remove the threaded rod and
> quill, does this give potential for a 'long boring auger' type set up??
No. The way to do long hole boring with the major, the minor and the elf is
to put a special device in the cross slide, or 'banjo' in place of the tool
rest, make sure it is all aligned with the driving centre and then feed the
auger through the device, with the tailstock assembly swung out of the way
under the bed bar.
Ask Derek on Monday.
You would also need a 1 M.T. counterbore tool and an auger, both of them for
a 5/16" hole if you are making table lamps. Don't buy a kit, as you wouldn't
need the other parts for your lathe.
My preference is for a shell auger.
> Many thanks also for the phone contact details for Derek, I'll ring him on
> Monday to see about a replacement threaded key.
Check for wear on the threads on the ejecting rod and also inside the quill
as well. The replacement cost might be cheaper than lost time if they
suddenly 'go'.
Pleased to be of service, and happy that you are now up and running again.
Regards,
Reg. (U.K.)