Member postings for Graham Rounce

Yes, that's why I was thinking of square-profile threads, which should cause very little up/down bending of the screws? At the expense of more friction, maybe.

Talking of which, Paul Lousick, where can you get round rod threaded with a square profile thread? I hope you didn't mean "square rod", like a rack?

Howard: I haven't worked out all (most of) the details, tbh, but yes, I'm sure a "winch" will be needed.

Andrew: Yes, obviously.

Edited By Graham Rounce on 21/05/2019 01:12:30

Luddite! Lol

Oh. Well, it's just an idea. I'd like to see it in action, even so.

It started off when I saw a basque being tied (zig-zag ribbons down the back). Very decorative, but a lot of trouble! So I was idly musing about some kind of electric assist.

Now even I can think of other, more suitable, things than what I've described above, but I've become sidetracked by the interest of making one, which I haven't seen before.

That's all!

Hi, and thanks for all the advice, and the terminology info. I didn't know you could grt square threaded rod! I hope we can keep MI5 out of this.

Enc is a pic of what I have in mind. It's supposed to be a compact puller. The two gears at the left cause the leadscrews to turn in opposite directions at slightly different rates, in turn causing the pinion to move along, slowly but powerfully.

I've drawn triangular teeth because it's easier, but square would be better. Steel, probably. If necessary, there could be pinions above and below the one shown, to help stop the screws bending.

In the end, I'd like to make it even more compact - 1/4 the size shown, if that turns out to be possible.

Btw, I just mentioned the woodworking lathe. I don't think it will be of much use for this

Thanks again,

Hi. I would like a few wormscrews, say 4" long by 5mm dia, in brass, but all I can find are much shorter than that. Also some spurs with concave teeth so as to mesh as well as possible.

I'm thinking that a piece of threaded M5 won't be ideal, and that a "squarish" rather than triangular tooth shape would be better, to avoid slippage of the spurs.

I've Searched several times for the worms, but found nothing but highly expensive custom-made stuff.

Can you get dies, similar to screw-cutting ones but with a different profile, for making them with?

Thanks, Graham.

PS: I only have a woodworking lathe.

Edited By Graham Rounce on 19/05/2019 22:40:57

Can you not clamp a piece of hardwood (20mm?) to the metal before starting the drilling?

Or instead of clamping, drill a couple of 4mm holes for bolts and nuts to keep it in place, if you don't mind an extra couple of holes?