Member postings for Robin King

Philip,

From info on the Boxford Use group I understand that we have lost John.

Robin

Peter,

The page you are looking for is page 716, 8th June 1961 which gives the g.a. drawing of the Rob Roy valve gear plus reversing lever.

Michael - 'artistic license' - that's very generous of you, thank you.

Hopper - If you shim between saddle and apron do you then not also upset the relative positions of half nuts and leadscrew in the process? Maybe I'm not thinking that through properly.

To clarify part numbers for Bob's benefit - reference 122 is the 'eccentric shaft' not the gear. The lower gear - referred to on the parts list as a 'counter pinion' is reference 119. There are two different versions of this - one for 8tpi imperial (A6513), or metric 3mm pitch (10296). The numbers in brackets are the original Myford part numbers. The other numbers 119, 222 etc that I mentioned earlier are more correctly the part reference numbers used by Myford on their drawings.

I would assume (!) that both pinions are the same, but, the lower one appears to be free to rotate on the eccentric end of the lower shaft and is shown retained by a circlip, reference 123 (Anderton external type, 5/16 inch). The upper pinion is fixed to the handle spindle but no details are given of the fixing method; press fit?

Looking at it again, Hopper's description as 'throated' is much better than my misleading one of 'semi circular', so apologies if I've over elaborated it and caused confusion.

The centre distance between leadscrew and handle spindle is fixed, leaving the only adjustment available by rotating the lower gear eccentric shaft. I'm a bit cautious about the idea of being able to 'over engage' that gear with the underside of the leadscrew given the small diameter of the shaft and limited leverage available to achieve it. The means of rotating it are not clear from the Myford drawings so I can only assume (dangerous word, that) it's by finger pressure on the underside of the gear once the shaft retaining grub screw is loosened. Has anyone ever done it?

Michael,

Your sanity is our highest priority, of course! Maybe this'll help?

The original manufactured form of these gears is with a near semi circular form tooth machined into the bronze gear circumference so that the teeth effectively wrap part way around the leadscrew. They are not in simple straight cut sprocket form. I can understand that at first sight it might appear that the gears are excessively worn, but probably not so; that's how they were made. Thinking about it and in light of using mine for nearly forty years the only way that the teeth will wear excessively is if the gears are prevented from turning while the leadscrew rotates, either manually or due to seizing, but otherwise they are free to turn therefore wear should be minimal, assuming reasonable lubrication, adjustment, and normal handling. I'd still look at cleaning, adjustment and lubrication as the first steps before investing hard earned cash on a new set.

As luck would have it I've just crated up my ML10 for a house move so can't check it, but I do have the Myford owners manual to hand which has the section drawings and parts lists in the back. On section D-D that shows the upper shaft (for the carriage handle) as part no 228, and the lower shaft as part no 122.

No. 228 is the handle spindle so rotates and does not have any eccentric adjustment, but does have a groove in it for the retaining grub screw (part no. 120), visible immediately behind the carriage handle as Roger mentions.

No. 122 is listed as 'eccentric' and appears to be intended to be rotated to raise or lower the lower gear to engage with the leadscrew. If set too low it will allow the leadscrew to deflect downwards out of engagement with the carriage handle spindle gear and may be the cause of your problem - worth checking. No. 122 is drawn with a groove in it for a retaining grub screw, part no. 124, which is inserted from the right hand edge of the apron.

If adjusting 122 doesn't work then have a good look down behind the apron - I was surprised to find large amounts of swarf down there on mine, which could easily fill between gear teeth causing problems. Worth a look.

Afterthought on felts, vintage vehicle part suppliers stock suitable felt sheet, you'll have to search for them tho'.

Oddly my Boxford has no felt wicks anywhere and I've not seen mention of them ever being fitted on them either.

That's quite likely but the problem is finding them. You could try John Ward at latheparts.co.uk but I'm not sure if he's still trading; last time I spoke to him he was trying to retire. Worth a try though as he might be able to make you one.

Another thought, bit late possibly, but there is a useful manual in existence for the rebuild of the South Bend lathes, 'A Guide to Renovating the South Bend Lathe 9" Model A, B, C Plus 10K" which is fully illustrated and details the strip down/rebuild of those machines, nearly all of which applies to the clones as well. IIRC I bought my copy through Amazon, and it was well worth the money for my Boxford rebuild.

Ian,

thank you - that's very helpful. As and when I can download it I'll have a play with it and see what can be done/set up.

R

Thank you both. R

Ah so. In my ignorance - what's the difference from UK imperial dims?

Afterthought - does anyone know if that package can use UK imperial dimensions?

FWIW I tried downloading the 2D version a couple of days ago off the original quoted link but it was indicating a download time of more than 2 hours. Even allowing for our rural broadband that's a bit too long for me so I abandoned it. Nonetheless if the Youtube videos are to be believed it would be worth trying at the very least so I'll have to give it another go soon from IanT's link, though that wasn't working this a.m.

That's a shame, I was looking forward to a recipe for 'bubble cake' ......

There are several possible causes for the play you describe.

Looking at the exploded parts diagram in the handbook the rack is a separate item fixed to the back of the main quill with screws at top and bottom. I suspect that if the fixings worked loose it would allow some slack there.

I can't see if there is any provision for mesh adjustment between the rack and feed spur, though you could try shimming between the mounting face of the rack and the quill body to achieve that.

The other more likely possibility is wear in the quill top radial ball bearing and bottom taper roller bearing. There is a nut and washer on top of the quill spindle above the top bearing which according to the handbook is provided to be adjusted to take up axial play. It goes on to say that 'This nut can be reached when the quill is removed from the machine.' Looks like the first thing to check.

The Arboga handbook says 'when milling the quill should be firmly locked' so you're doing the right thing. It also mentions on cutter sizes/feeds guidance ' we have good results milling in steel with an end mill of 14mm (9/16" diameter to a depth of 4mm (5/32". I would assume that those figures applied to a new machine not one with some wear and tear on it. If you are attempting to doing anything more than that you might pull the quill down against the lock.

An ER32 collet is not the most secure for grip on an end mill shank, and they can pull down with a heavy cut. On my EM825 I use a Clarkson collet chuck that came with it plus threaded shank cutters and have never had any great problem, also I try not to be greedy with cut depth/feed rate.

Btw - you might find a copy of the handbook on the net, but otherwise from Tony Griffiths at lathes.co.uk

Same here, hence my question earlier - does seem like overkill.

The one thing that has struck me with both my mill and lathe being on Polymax resilient mounts is that the machines are now noticeably quieter than when on solid mounts direct to concrete.

Two suppliers you could try:

www.wixroyd.com - search for 'machine mounts';

www.polymax.co.uk - FMG heavy duty levelling feet.

I bought four for my Arboga mill from the latter and very good they are, but not cheap.

The only snag is that for the load you are looking at the stud sizes are M16. If you can work with about 300kg then M12 studs are available from Wixroyd, and 350kg from Polymax.

Obviously re-check and repeat the process until the error is corrected.

Dave, many thanks, that's just the info I was after and makes sense on looking at it again so I'll work on that basis.

Clive, thanks. The method I was shown years ago was to use a surface plate but to rotate the level until it centres correctly, which it must do at 90 degrees to the slope (if any), place an angle plate alongside it held in place to use as a lateral reference, then turn the level 180 degrees and place alongside the angle plate to check if still centred. Adjust the level as necessary; no need to adjust the surface plate.