Thanks Brian. So no contact at all in the old narrow guide area, all exclusively by the two outer shears front and rear?

Not as good as the Mighty Drummond with its narrow guide of course, but doesn't seem to be a problem on he ML7 I recnelty converted. The cutting forces all bear on the rear shear, which means there is that tiny clearance between the gib strip and front shear, so no squishing to speak of.

The series of articles John Shrubsole did in MEW back in the '90s on refurbishing an M-type Drummond included doing his version of a wide-guide conversion to use the rear of the rear shear. He reported no problems.

Excellent, Brian. That settles it. Thanks much. Confirms what I had assumed, but we all know how assumptions go!

That's the other thing with the Myfrod, the rear wide-guide surface is almost twice as long as the narrow guide, and acutally lines up with the full length of the gib strip on the front shear, always a good idea you would think.

Yes, the narrow guide is 4-3/4" long, the wide guide 7-1/2". Front shear is 2" wide and overall from front of front shear to back of back shear is about 4.5" from memory. So wide guide ratio would be somewhere over 1.5 to 1. Have never heard any complaints from later Myford owners about jamming etc so it must work. I do remember reading somewhere that a ME letter to the editor writer had converted his brand new wide guide model back to "proper" narrow guide though. Probably went on with his next lathe to convert the roller bearings back to bronze bushings!

Yes, I found the unused rear shear a bit rough, as if it had been maybe milled. Gave it a touch up with a slip stone before pressing it into service for the wide guide. Not quite the "Rolls Royce of Lathes" then but still doing a good job for a 60-year-old machine I reckon.

I wonder what Myford does these days if you send a bed to them for regrinding? Grind the tops and grind or mill the sides?

Edited By Hopper on 05/12/2017 13:24:42

One certainly could. And this is something that gets forgotten amongst the "Rolls Royce of Lathes" mythology. The original ML7 was designed and built to be a reasonable cost lathe. When it first came out it cost about 35 quid, compared with 42 quid or so for a Drummond m-type, the pre-war favourite of model engineers. And I think in later years it was still a lot cheaper to buy than a Raglan or Boxford machine. I would say the milled vertical shears could well be part of that cost saving philosophy, along with the Mazak diecast apron, H-frame, bracketry etc. It's actually a very clever design in the way it keeps production costs down while keeping quality up to a suitable standard for home hobby use. It's very simple throughout and machining time was minimised with the use of that diecast Mazak. Maybe the later Super 7s were more in the "luxury" class with cast iron aprons and taper bronze bearings etc, but still more of an Austin Princess than a bona fide Roller.