Lathe problem

[hawkeyefxr]

I was working on my Record DML305 lathe today using a 3 wheel steady as the work piece was about 8/9 inches long. I stopped the lathe to adjust the dust hood, on starting it again for a fraction of a second i noticed the work piece did not move then the was a clack and it ran. Later i found out what it was, the chuck had come undone very slightly. I now have a chuck jammed on the thread and just cannot move it.
Record have told me before to use the indexer lock to undo the chuck (i know this is not a good idea) as there is no way to use tommy bar hole as they have not provided any, i think i have knocked off an indexing point inside but the chuck is still firmly jammed on.
I have removed the pulley back to the shaft hoping to knock the spindle out but the spindle bearing fit it to tight for that.
I thought i would warm the chuck gently but the rear of the chuck has a plastic cover which i can't remove for some reason, i have had this off before when i little CA got inside and i had to clean the chuck out but con not remember anything that should hold it in.
I have phoned Record who are supposed to phone me back. I think this is a design fault really as all it would have taken is for a hole for a tommy bar to be put in and there would be no problem.

Any ideas gratefully accepted

 

[Ricardo Shilly Shally]

I had a similar problem a while ago though not on a Record lathe & ended up drilling 2 holes through the hand wheel on the back of the headstock to allow a tommy bar to pass through. This allowed me to lock up the spindle whilst I put another bar between the chuck jaws & taped this with a mallet until the chuck was loose.
Don't know how if this would work for you, Ric

 

[Penpal]

I had a similar problem a while ago though not on a Record lathe & ended up drilling 2 holes through the hand wheel on the back of the headstock to allow a tommy bar to pass through. This allowed me to lock up the spindle whilst I put another bar between the chuck jaws & taped this with a mallet until the chuck was loose.
Don't know how if this would work for you, Ric

I like this idea and after fit a washer before screwing up the chuck. Welcome to the forum Ricardo.

Peter.

 

[Louie_Powell]

Been there, done that.

Your chuck has either a hole for a tommy bar or a hole for a chuck key - in either case, that provides a means to grip the chuck. Alternatively, you can lock a scrap of wood between the jaws of the chuck to create a handle. So the problem is gripping the headstock spindle.

Options include:
1. the ideal solution is to have either a hole in the spindle shaft for a tommy bar (usually a feature in large lathes, but not always in midi- or mini-lathes), or a true spindle lock. I agree with you - the indexing stop isn't designed for breaking loose a stuck chuck, and if you try to use it for that purpose, you are likely to break teeth off the indexing wheel. DAMHIKT)
2. If your lathe has a handwheel, you may be able to get enough of a grip on it to hold the shaft steady while using the chuck key/tommy bar to break loose the stuck threads
3. On my lathe, the shaft between the outboard end of the headstock and the handwheel is long enough that I can get a wrench on the shaft. I use what we in the colonies call 'slip joint wrench' - an adjustable wrench with serrated teeth that will grip reasonably tightly onto the shaft, and that have a long enough handle to be able to apply some torque (see picture). Yes, this will scratch the surface of the shaft, so you probably want to limit the number of times you do it. Alternatively, the nose end of the spindle shaft may be long enough to grip with a wrench.
4. Another option is a strap wrench - basically, a length of leather or plastic that wraps around the shaft and that has a handle that wedges the strap in a way that grips the shaft. My experience with these is that they tend to slip rather than grip tightly enough for this application.

Using a plastic washer on the spindle shaft is a pretty good way to minimize the risk of jamming a chuck or other threaded fixing onto the spindle. The problem with them is that if the washer isn't flat, it can introduce runout. I make my own washers from various throw-away plastic items - lids from yoghurt containers, or the plastic boxes used to mail software CDs. Because the plastic is throwaway, it's cheap enough to make several and then throw away any that prove to not be flat enough for the purpose. Use a forstener bit to drill a suitable hole in the plastic to just fit over the spindle threads, slip the plastic over the spindle and thread something onto the shaft to hold it in place (a bottle-stopper mandrel works well), and then with the lathe running, use a skew to trim the plastic to form the outer edge of the washer. Finally, sand to remove any distortion on the edge and try it for flatness.

 

[hawkeyefxr]

Like your description Louie. I do have a couple of pairs of pipe grips but could not bring myself to use them (as an aside the ones you show are killers, those circle bits that allow adjustmentioned wear, when they get work they can slip and pinch your palm. Have seen it many times).
As to the leather washer never gave that a thought though I did think I saw the chuck not running true when I got everything back together. I was going to check it today with the DTI. Also like the idea of milk plastic bottle's for washers. Will get a couple of bits of tube shaped as hole punches.

 

[Walter]

According to the manual the dml305 has a hole in the collar of the spindle nose (between chuck and headstock - see fig 8.12 on page 11 of the manual - see link).

Inserting the knockout bar into this should enable you to lock the spindle either by hand or against the bed.

A bar held in the jaws of the chuck can then be used as a lever to free it.

http://www.free-instruction-manuals.com/pdf/pa_1404086.pdf

 

[Ricardo Shilly Shally]

I like this idea and after fit a washer before screwing up the chuck. Welcome to the forum Ricardo.

Peter.

Thank you for the welcome. This isn't my idea my teachers lathe has this feature built into his lathe I just copied the idea

 

[hawkeyefxr]

Walter, the knockout bar is for removing the morse tapers. The book does say use it in the spindle but there is no hole for it. I phoned Record and they told me the book was not correct and to not do the chuck up tight AND use the indexing lock. Well as i have said the chuck being tight was an accident so i did in fact use the indexing lock and yes snapped one of. This is why i say it was a design fault, i was waiting for the warranty dept to phone me back but i guess they must be over stretched with claims, or perhaps they think i will disappear :-).

I have also checked the chuck runout now that i am using a wash, the chuck runs out by 12 thou, i checked the spindle and that is 2 thou, acceptable, i checked the chuck adapter and it's out by the 12 thou. Would this be acceptable on a wood lathe ?

 

[Walter]

Er, yes, I do know what the knockout bar is for.

If there is no recess in the collar for the bar to fit into then I suggest you grip the collar with a strap wrench.

 

[Neil Lawton]

There's a hole in mine.

 

[Walter]

There's a hole in mine.

As indeed there is supposed to be. I have seen others with a hole too but as I have no doubt Ken would recognise a hole when he sees one perhaps Record Power have, either by mistake or design, produced a batch without them.

I am also surprised (well, to be honest I am not actually) at them suggesting the use of the indexing stop as a locking mechanism.

 

[Walter]

I have also checked the chuck runout now that i am using a wash, the chuck runs out by 12 thou, i checked the spindle and that is 2 thou, acceptable, i checked the chuck adapter and it's out by the 12 thou. Would this be acceptable on a wood lathe ?

The 2 thou run out on the spindle is par for the course for a woodturning lathe. Have you checked the run-out of the chuck without the washer. That could be the cause of the additional run out.

 

[hawkeyefxr]

Yes it was the same 12 though.
I phoned Record and they do not transfer warranty, that I expected. How ever they will replace the chuck adapter under warranty as it's this that is out. Just got need to find the receipt.

 

[Penpal]

After much rereading how did you free up the chuck. Any damage?

Peter.

 

[hawkeyefxr]

I removed the hand wheel, there is a flat on the shaft spindle where the grub screw bites onto. I used an adjustable spanner done up tight as there is no opposite flat. I then remover the jaw carriers then used a Tommy bar in the slides where the jaw carriers slide in and out. It was a fair ol grunt but it came off in the end. I also used a blow torch to gently was the collar.

 

[21William]

Not having a hole in the spindle is a serious oversight. I wonder if it's a "feature" Record have left off for some reason or whether yours just slipped through the net undrilled?

 

[hawkeyefxr]

A bad omission in my book.

 

[Penpal]

WEll done to overcome the problem Ken every day a new one.

Peter.

 

[wm460]

Success at last.

 

[Penpal]

Pictures always help in solving problems.

Peter.