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

[Brian JohnParticipant @brianjohn93961]

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 ?

[Brian JohnParticipant @brianjohn93961]

How to grip the rod firmly ?

[GarryCParticipant @garryc]

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

[David Clark 13Participant @davidclark13]

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.

[pgk pgkParticipant @pgkpgk17461]

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.

[Les Jones 1Participant @lesjones1]

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

Les.

[Neil WyattModerator @neilwyatt]

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

[KWILParticipant @kwil]

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

[Brian JohnParticipant @brianjohn93961]

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.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by KWIL on 15/08/2015 11:37:54:

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

.

+1

[Oops … evidently the wrong answer]

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

[Brian JohnParticipant @brianjohn93961]

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

[JasonBModerator @jasonb]

Posted by Brian John on 15/08/2015 11:55:48:

I might also look at getting a better vice.

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

[Brian JohnParticipant @brianjohn93961]

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

[JasonBModerator @jasonb]

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

[Brian JohnParticipant @brianjohn93961]

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.

[Frances IoMParticipant @francesiom58905]

buy one with removable hardened jaws (eg most Record vices) and make your own jaws from mild steel 20mm x 10mm fits the 100mm jaw size well and also allow you to cut a 3mm slot along top edge of jaws – 10mm allows you to sink the retaining screws below the v notch which can be cut on a small mill on an angle plate (or I guess filed)

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

[Neil WyattModerator @neilwyatt]

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

[JasonBModerator @jasonb]

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.

[roy entwistleParticipant @royentwistle24699]

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

Roy

[Anonymous]

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.

[Malcolm HarveyParticipant @malcolmharvey97633]

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

[Brian JohnParticipant @brianjohn93961]

Having experienced carbon steel dies, I now only use HSS taps and dies.

It looks like my next purchase should be a decent bench vice and never mind the V grooves. Would something like this be suitable or should the jaws be plain flat steel ?

http://www.ebay.com.au/itm/Pro-Series-Bench-Vice-Swivel-Base-4-inch-/221610885187?hash=item339909c043

Edited By Brian John on 16/08/2015 14:18:40

[Neil WyattModerator @neilwyatt]

Try it. At that price you won't cry if it ends up as a doorstop.

Neil

[Frances IoMParticipant @francesiom58905]

looks like a Record lookalike – the jaws are prob held on with UNC 1/4″ with a flat 10mm wide pan head so making your own jaws are easy with a miller

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