Member postings for DiogenesII

Discussion of purpose and Dimensions of F36 Stop Peg here;

Thread; 'ML7 Stop Peg'

Collar 1 looks like F35 Tie Bar Spacer

The longest stud looks like F37 - don't know about the other two, will become clear during assembly, I guess..

F34 fits on the Eccentric Shaft F47, where it is secured with the screw - the other hole accepts a threaded pin F36 which acts as a positive stop for the Swing Head Assembly.

5 looks like a threaded oil nipple, I don't know where it goes, sorry.

6, ?

Are two of the screws F39?

Nicely done

..a couple of observations, don't know whether of any value or not..

You suspect the bottom one engages first - many lathes of a similar pattern use shims between the apron and the saddle to ensure that the halfnuts are centrally-disposed to the leadscrew and can close on it together..

..if you loosen-off the apron (beware of shims already in place) and then close the half-nuts onto the screw, does a gap appear between the saddle and top of apron?

..before you do this, it might be worth checking the fit of the damaged half-nut with the leadscrew, just to make sure that there are no burrs causing it to 'ride' on the threads.. ..if it's been closed with enough force to bend the cam pins in some previous life, anything is possible, sometimes a little restoration of the thread form is necessary

They are really nice, it must be satisfying knowing that they are going to be there for posterity, too.

..if the flow needs a tweak, I wonder whether a (tiny) breather hole might help - it's only a vague musing, I've been experimenting with wicked burners recently and found it doesn't take much 'vacuum' to overcome capillary attraction..

Great job..

"Is was this a good deal?"

No.

..it started at £300 today..

There's a great moonrise happening in Gloucestershire at time of posting - just breaking over the horizon to ? N of E, huge and exactly the colour of a pumpkin..

Edited By DiogenesII on 22/11/2021 18:33:16

Edited By DiogenesII on 22/11/2021 18:34:06

..and put a generous chamfer on the end of the stock to help start the thread..

Just 'cos no-one else has raised the point, are there specific issues with the lathe that mean things aren't very satisfactory?

..if you are going to be using it to make blanks, arbors to mount them on, etc., the I guess this might be as good a place as any to address any shortcomings?

It is very similar to the Birch.. ..do you what taper it has? ..and what threads the fasteners use ..it might provide a clue..

..it's similar to (but not0 a Burke - there were several small American mills of a very similar style all around at about the same time, these often use a Brown & Sharp taper in the arbor - the sizes are very close to Morse, some careful measurement might be needed to establish what you have..

Edited By DiogenesII on 17/11/2021 17:57:33

A rub on the blade with a candle or timber / tyre crayon works well on steel and aluminium..

Hi Harry.

The recess in the round 'bearing block' is approx 3.75mm deep (housing a bearing + two hard washers total thickness 4mm) - so outer washer sits c. 0.25mm proud of the face. Bearing is a 1226, I think - the recess is 27.30-ish diameter...

The handwheel 'boss' upon which the adjustable collar is located seems to be unmolested, lengthwise - the collar is (as near as I can tell with feeler gauges) c. 0.15mm or so shorter than the boss, so that there is clearance for it to rotate without binding when the complete assembly is all in situ and tightened up. Hope this is clear / makes sense.

I have some reservations whether the boring of the bearing block will be feasible unless you have access to another lathe to do it on, or can find a spare (or even make one).

As Nick says, and I hinted at the beginning, I'm not at all sure that much is to be gained - the greatest thrust comes when cutting (towards the headstock), and the bearing already fitted at that end of the leadscrew takes care of that - at best this will only ease the action of returning the saddle to the 'tailstock end' - a circumstance which is only really coping with the resistance of the carriage - if the action of moving the carriage feels stiff, recheck the adjustment of the saddle clamp and setting screws.

If you do decide to go ahead, DO check all measurements with & against the fittings on your own machine to check that everything will fit and work together as expected.

PAY particular attention to the depth of the recess and the relative position of the shoulder on the leadscrew - the bearing must seat in the bottom of the recess, and not on the leadscrew shoulder!

Kind regards

D.

Edited By DiogenesII on 16/11/2021 06:44:11

Edited By DiogenesII on 16/11/2021 06:50:22

Okay - there's a recess that is cut in the round 'bearing block' that is screwed to the square endplate at the tailstock end.

..without measuring up (I have to go to work) I can see that the main issue is that the bearing is of a larger diameter than the boss that bears the adjustable collar - I think the collar must have had a face skimmed to provide a running clearance, which could be part of your 'binding' problem - I'll measure later and see what has been done.

In closing (for now), I must point out that it's not a practical proposition to remove all backlash from the carriage leadscrew using the standard components - a little clearance is necessary in order for things to move freely, and on mine this translates to about an eighth-of-a-turn at the handwheel. In practice this is not a problem, there are established methods of compensating for backlash on manual machines, maybe someone with a little more time will provide a fuller answer, or can point you in the right direction!

The mod has been done to mine (although I'm not entirely convinced how much value it has - there is already a thrust bearing at the headstock end).

Be that as it may, I'm not sure that it's simply a question of 'sticking them in' and doing it all up again - I'm more-or-less certain it requires 'metal-off' the ?outer?inner? collar.. .possibly in a first for this forum, I have to admit that a certain amount of Speyside precludes me wanting to go and look now - I'll go and check for you in the morning..

The end-float problem is a question of trial, error, 'feel' and patience, I'm afraid - the best advice is to not overtighten the locknut, but only nip-it-up enough to stop the handwheel unscrewing.. ..do it, re-do it, move it a bit and do it again, eventually it will come right..

..I hope people will forgive me for saying that many Picador components (bearing blocks etc.) were cheaply made for light duties and not all are suitable for the kind of sustained high-speed-machine-tool-drive work that one occasionally sees them being put to in items being sold through auction-sites and classifieds..

It depends what Picador components are being used where..

By way of a 'bump'.. ..I don't have a WEG, but the 'Quick Start Guide' pdf from their website seems pretty straightforward, page 8 shows how to set up a remote 'button' (electronic) potentiometer, but not a rotary (analogue) one - which do you have?

..did it come from IDS at the same time?

..I know that there are people on the forum who can do stuff like this in their sleep, hopefully someone more knowledgeable than I will respond..

Here;

Rennie Tool Co - M42 8% Cobalt..

..labour's a wee bit more expensive in this country.. £18.66 a stick.. ..only 4 left!

Did find these tho' - worth a look for milling cutters;

MR Tools - Special Offers

Edited By DiogenesII on 13/11/2021 18:12:14

If it's an ML7 I'm fairly certain will be a small bore, using a standard myford 1 1/8" thread, the Big Bore S7 is a 40-something mm metric size spindle nose - the backplates & mountings are totally different and not interchangeable, to the best of my knowledge - maybe someone can confirm..