Cutting a thread on 2mm and 3mm stainless steel rod.

How do you cut a thread on 2mm and 3mm stainless steel rod ? How do you hold it so that it does not slip when using the dies ? I have cut threads on 3/16 inch brass pipe by clamping it in a heavy vice but even then there was some slippage. I do not think clamping 2mm and 3mm stainless steel rod in a vice will work.

My lathe should arrive later this month. Would a lathe chuck hold rod this size firmly enough ?

Hi Brian

Just in case it may be of use - I made one of these but I was holding 5/16" stainless for threading at the time - so maybe this is not suitable unless you can cut the small diameter needed for your job. I have used similar for smaller though - but not down to 2 - 3mm.. It's never left a mark on the work..

Cheers

Garry

I would use an ER collet chuck in the lathe. This would hold it true and tight. I doubt a standard three jaw chuck would hold it without marking the outside diameter.

Friction is a function of contact surface and pressure. A fine v groove would give a third edge of grip or a suitable softer material for it to bed into in the vice jaws or perhaps just some folds of paper or if prepared to risk scratches if it slips then sandpaper. lathe chucks with three or four points of contact (or day-dreaming of a 6-jaw) also have hardened serrations to 'bite in'. Collets better still.

You could try loctiteing into a hole in some metal that you can grip the heating it to remove it.

Les.

Hello Brian, I remember your threading troubles.

Over the last couple of weeks I have cut several threads M4, M5 and M6 in stainless with no slippage. In one case I used a bit of aluminium to grip the (partly threaded) 5mm spindle in a three-jaw chuck when threading the other end M4.

I've been able to thread stainless M6 using fibre jaw grips in my vice.

Neil

Screwcut it in the lathe, much easier than trying to push a die down it!

KWIL : I think it will be a while before I am confident enough on the lathe to do thread cutting with it.

I think the collet in the lathe chuck might be the best option. I might also look at getting a better vice.

.

+1

[Oops ... evidently the wrong answer]

Edited By Michael Gilligan on 15/08/2015 11:58:10

If the lathe chuck could hold the rod for screw cutting then surely it can hold it for using a die ?

Thats your best bet until you get a lathe as what you have is not what most of us would term a "heavy vice"

"If the lathe chuck could hold the rod for screw cutting then surely it can hold it for using a die"

You can make several shallow passes when screw cutting to build up to full depth, this puts a lot less force on the work so it is less likely to slip.

Edited By JasonB on 16/08/2015 07:44:33

I am looking at new vices on the internet right now Do you have any recommendations ?

Just get a proper bench/fitters vice rather than the drill vice you have at the moment. Don't go too cheap as the quality can be poor, 100mm wide jaws should do you.

These are heavy so try and find something available locally rather than us suggest something from the UK.

Edited By JasonB on 16/08/2015 07:55:20

The bench vices I can see here do not have the horizontal and vertical V notches. I think these are essential for what I want to do.

Edited By Frances IoM on 16/08/2015 09:27:56

A decent bench vice should not need v-jaws to hold things firmly.

I've threaded M12 holding steel in my Record No.3 and it's pretty old and battered.

Neil

Brian as Neil says you can manage without Vee grooves I do, couple of bits of aluminium angle as soft jaws will grip your stainless OK.

The original post was screwing 2mm & 3mm rod I couldn't screwcut that on my lathe without some modifications of the steadies

Roy

Using a decent die you won't need that much of a clamping force for 2 or 3mm stainless if it's the usual 303,304 or 316. Just been die threading some 4mm 303 and it was a doddle, I find I don't need to really clamp the vice up until doing M6 in stainless.

I own a 1962 Rover 100. I have made new studs for a lot of engine components (thermostat housing etc) using 1/4", 5/16" and 3/8", 303 stainless rod. I gripped the rod in the 3 jaw in the lathe (ML7) and used the tailstock dieholder to get a start, down to the thickness of the die to make sure I had got it running down the rod square. I then took it out of the lathe a did it conventionally in the vice using a diestock and tapping grease. I have fibregrip jaws in my vice. I had no slippage or marking of the rod on either device. I was of course using HSS dies.

Edited By Malcolm Harvey on 16/08/2015 13:29:42