Myford milling attachment and vice.

[jack620]

Hi All,

I have a Hercus lathe with a slotted cross-slide. I have the Hercus milling attachment for the lathe, which is my only milling capability. Some time ago I acquired a Myford milling attachment and a Myford vice. Although the Myford milling attachment is less capable than the Hercus, which can be rotated and tilted, it will be quicker to setup. I think it will be handy to have for quick and dirty jobs.

Today I finally got around to mounting the vice on the milling attachment. There are a couple of issues with this combination. I’m not even sure if the two are intended to go together. Perhaps one of the forum's UK members can clarify that?

The slots in the milling attachment are 9.3mm wide, which is a fraction under 3/8”. So I assume Myford intended the user to use T-nuts with 5/16” or 8mm threaded holes. That’s fine, except the notches in the vice casting are slightly over 3/8”. I think using 5/16” bolts in these notches would result in a sloppy and unsightly setup. So I elected to make slightly undersize 3/8” T-bolts from 16mm square stock that fit the slots in the milling attachment.

The other issue is how close the T-bolts are to the edge of the slots in the milling attachment. It looks to me like the bolts will place stress on ends of the slots, thereby risking a cracked T-slot.

Finally, the base of the vice is significantly concave. I intend mounting the vice in my Hercus milling attachment and taking a skim cut with a large fly cutter.

What use did Myford intend for this milling attachment? Was it meant to take a vice, or are you supposed to attach the workpiece with T-nuts and toe clamps?

Appreciate any comments from the Myford owners.

 

[goldstar31]

Initially, the amount of information about Fixed and swivelling vertical slides would fill a number of books and arguably, George Thomas's Model Engineer's Workshop Manual is as good or better than most.
It was written for the Myford and the Hercus is a pretty good copy.

Myford made their lathes to their designs and tough if you want to deviate from them. OK, I do it and have done it over the years but it would take too long to explain. Thomas also hung a small dividing head on his slide and that was in his book "Workshop Techniques'

Arguably, with care you can do most things on the skises but you are right in assuming that both Myford slides and indeed the boring tables are somewhat thin and precisely that is why Myford moved away from what are known as 'standard tee slot sizes' To get the lathe to swing 10 inches etc demands 'compromises'. You can bend the slides and you can crack them. I can swop both my Perfecto lathe slide - which has Myford Tee slots and my Myford one onto my Sieg C4- and mine has a mill drill attachment.
Oddly, I bough a handful of Myford Tee nuts at a UK show and found then with 6mm tapping.
For what it is worth, my slides will take dividing heads, rotary table, chucks and a potts mill drill spindle for starters. Sticking vice on it is only a beginning.

I'm sort of commissioning an almost new Super 7 with gearbox and power cross feed- and the bits mentioned are going on the boring table and the slides.

So I wish you good fortune

Norman

 

[jack620]

Oddly, I bough a handful of Myford Tee nuts at a UK show and found then with 6mm tapping.

Thanks for the reply. Perhaps 1/4” or 6mm is the correct size T-bolt? That would make the ⅜“ slots in the vice’s base even more absurd.

 

[goldstar31]

Obviously you have missed the use of 'extended' tee bolts. I DID infer that you were only at the start of bolting things down on Myford slots. The only 'absurd' thing about a Myford is the dedication of tooling to suit Myford.

The car industry and electrical appliances are more obvious candidates. Thomas- and the books are relatively old about fastenings do make suggestions but I still have a bloody ( pardon) drawer full of might come in useful taps and dies.