WARCO WM-250 thread dial

Having installed the Warco 250vf and eager to play I thought time to use the whining wheels and carriage mover part and cut a thread, I followed the destruction of whats wheels go where and tore up the invoice to set the backlash in the gear train a touch of chain lube and away we go…. Ah… the thread dial is not turning, its not in mesh… allen key adjust start again… CLUNK CLUNK CLUNK…. hit the big red button!

It would seem the drive gear is just kissing the lead screw and the milled keyway is hitting the teeth, did some investigations and the gear is riding miles too high above the centre line of the leadscrew. I took it all apart and there is no damage to the leadscrew but the fixing screw is bent and the ends of the teeth on the drive screw have been mauled, I contacted the service dept of warco and a very helpful gent has sent a replacement unit I fitted it tonight and its the same. Now my way of thinking is this, the fixing for it is too high up the apron body as the two castings are the same size I have thought about machining a new shaft to lower the gear into a better mesh. I wonder do any other WM250 owners have this issue? and could anyone have a measure up and see where there mounting holes are. I will add some pictures Any ideas or help please folks.

PS the replacement dial Warco sent has 6 numbers on the face the one as fitted has 4, the lathe is the imperial version.

Martin

Martin FWIW... I have taken a couple of pic for your att. from my 250V-F ... It is possible that the bracket on your machine may well be a different machine fitting, poss' a 180 or 240... ...

Dial as supplied...

Screw cutting dial gear in mesh...

Bracket fixing distance...

Bracket length...

Gear gap compared to yours...

It looks as though on your pic 3 the gear needs to go back further on the shaft...is this as supplied or have you had the gear off the shaft before writing your post.

George.

Martin, as George has said, it appears that the gear is not far enough on the shaft, looking at your second picture the securing nut is barely engaging on the threaded shaft. The gear and shaft are held in register with a key and each has a keyway cut into them. I am wondering if you have aligned the parts correctly to get correct engagement or is the gear just sitting on the end of the key. If so then this could cause the gear to sit too low and hence there is not enough thread to engage the locking nut properly.

Sorry if the above sounds a bit cumbersome.

Martin W

edit; Looking at your picture 3 you can clearly see the key set in the shaft. This should be fully engaged with the gear wheel and should not be visible. I suspect that this is causing your problem. 

2nd edit; If as you say the gear is riding too high to engage the lead screw then moving the gear further onto the shaft is not going to help, in fact it would appear that it would make the problem worse.

Edited By Martin W on 07/05/2016 18:36:47

Edited By Martin W on 07/05/2016 18:49:37

Gents. thanks for the comments thus far. The gap and the nut just on is how far down the shaft I have had to let the gear drop to get it to sit on the centre line of the lead screw.

Martin how do the measurements supplied by George compare to the mounting points on your lathe and the thread dial assembly?

Martin

George.

the measurements seem the same

Posted by Martin W on 07/05/2016 18:58:30:

Martin how do the measurements supplied by George compare to the mounting points on your lathe and the thread dial assembly?

Martin

Much the same. Martin,

So to continue the saga of bangs and clunks… Peter at Warco sent out a new threading dial and I tried it and guess what…. CLUNK CLUNK CLUNK… So better get this sorted I machined up a new shaft for the dial and made up a bushing to keep it from dancing about the gear now rides the lead screw on its middle line so the keyway does knock the granny out of the teeth and vicky versa. I have packed up the replacement dial and its on its way back to Warco, Tell me from the pictures posted by George on this thread and the replacement dial there are far more marks on the dial face is that important or just more chances at starting?

I have added these pictures to show the fix, I hope this won't invalidate any warrantee! I would hate to have to walk home from the makers with a bent lead screw on my shoulder.

Martin

Looking at the pictures between your lathe and Georges there is a difference in the alignment of the lead screw cover fitting. On yours the fitting screw is almost vertically aligned with the Thread Dial mounting hole whereas on Georges there is a significant offset. If the lead screw cover is the same then the lead screw has been moved relative to the apron on the saddle. in fact it now would be further away and could cause the problem that you are experiencing. I am wondering if WARCO have had a change of design or manufacturer and not updated the Thread Counting Dial to reflect the change.

It doesn't help your problem but it may be worth raising with WARCO.

Cheers

Martin W

The different numbers on the dial could be the difference between a metric and imperial one, did you check to see if the gears were the same number teeth?

Jason, I have counted the teeth on the one I have and thats 30 tooth, when i get home i will have a count of the warco replacement.

Still trying to get my feeble mind around how the numbers work on that and the maths issue of the change wheels.

Martin W...

I reckon you're on to something there...

'Tell me from the pictures posted by George on this thread and the replacement dial there are far more marks on the dial face is that important or just more chances at starting?'

Martin B ... Judging by the TPI chart numbered 1 - 6, I make the assumption that you should be able to pick up threading on any number diametrically opposite ea. other to get the same TPI ,instead of waiting for the dial to come round again...

i.e. ... 1 - 7, 2 - 8, 3 - 9, 4 - 10 etc.

Not having done any single point...yet ... always used the tailstock die holder for the small amounts I've done; so I am making the assumption...

As an after thought... check the positioning of your leadscrew centre, may be the design has been altered...

I might have sussed it, took some more measurements...take into account camera parallax error... your hole centre looks approx 11 - 12mm from the edge of your saddle... mine is 6 - 7 mm from the edge of my saddle, a difference of 5 -6 mm... voila! your radius of arc is greater than mine hence your gear will swing further round than mine hence contacting on the bottom of the gear not on centre line... if you get my drift, ...solution ... plug the original hole & redrill approx' 6mm closer to the edge of your saddle. I know you've already resolved it so to speak with the spacer but...

George.

George the centre of the leadscrew is about 26mm from the lathe bed casting. the move of the swing point is probably the thing. BY George you have got it!

Praps mine was built on a friday and the fitter was making for the door when he laid out the centre dot for the driller and was in a hurry to catch the tram home.