Thread: mystery metal

You might try seeing if it's non magnetic - most stainless steel is non magnetic - but not all.

Also the degree of rust can point in a possible direction.

It sounds a bit like untempered spring steel.

Rob

Originally Posted by kraits

but, as soon as the 4mm tap touched it, it bit in and snapped

Are you using a tapping machine/head?

Stuart

S/S can be tough to work on alright.
Did you use a taper tap first?

Jordan

Originally Posted by nearnexus

You might try seeing if it's non magnetic - most stainless steel is non magnetic - but not all.

Also the degree of rust can point in a possible direction.

It sounds a bit like untempered spring steel.

Rob

ive had this lenght of steel for over two years now, no rust, non magnetic, all the characteristics of stainless steel, i
did fail to mention that the week before i tried to drill a hole into it with a power drill and ended up with a couple of blue drill bits before i got through the stuff. i was tapping by hand and started with a starter tap which i no longer have in 4 and 6mm. im convinced it's stainless but with something else in it to make it even harder, bends like stainless, heavy like stainless, heats like stainless, welds like stainless but not your every day run of the mill 316 stainless steel. the fella i got it off worked for a mob that made ware plates so i wouldnt be supprised if its martensitic stainless steel but , it did drill ok in the drill press.

The little bit of stainless I've worked has always been a bastard to do anything with.

Soft to cut with a grinder/disc but hard/sticky to drill and tap.

Guys that use stainless regularly probably know a few tricks.

Rob

Were the taps in question Carbon Steel or HSS?

kriptonite

Originally Posted by Techo1

Were the taps in question Carbon Steel or HSS?

.
tap and drill set are VA with the blue stripe.HSSE base material with TiCN finish, should be good for cutting into steels of up to 1000 N/mm2.

Hi Kraits,

I'd be thinking something like 440C stainless.. If you want to do a spark test and see how it lines up with one of these..

Identification Tests for Stainless Steels

Regards
Ray

I think you may have answered your own question to some degree if it is a wear resisting variety of steel/stainless steel. Wear resisting materials are absolute buggers to do much with due to their design characteristics - they are designed to not be cut or quite often bent, which of course is what threading does.
Untempered spring steel taps quite nicely and rusts just as well, likewise Stainless of the 304 or 316 variety taps quite nicely and drills quite well, (if you know what you're about as far as speeds, lubricants and sharpness of drill bit go).
Unfortunately one occasion where the cheap material has cost more in broken tools than the correct material would have - we've all been caught at least once.

Originally Posted by Karl Robbers

Unfortunately one occasion where the cheap material has cost more in broken tools than the correct material would have - we've all been caught at least once.

it's difficutly always know what your getting when you get it for free from a mate who own's a fabrication shop up here, kind of a lucky dip, most times it's mild steel or 316 stainless but, every now and then what appears to be mild steel or stainless turns out to have a much greater carbon content (not stainless) and i get caught by suprise, particularly with the cutting tools feeling the brunt of it. not all that long ago i got what i thought was bright mild steel, went to turn it down and the tct bit wouldn't even scratch it, just slid along it, occasionaly i can (like that time) put it to use else where like in the forge i was able to shape it into a drift i now use for hammering out holes when making an axe, otherwise it just gets thrown under the bench in the hope there may be a use for it one day down the track because as we all know, as soon as i throw it out i will need it.

Hi

making brackets and "things" for a dual battery setup in a vehicle might be better made with mild steel which is not so brittle and has a bit of flex when driving on long corrugated roads etc etc.

I have used aluminium and steel in making accessories, etc and find that it has to be solidly bolted down to avoid vibration and flex failure, even in mild steel.
Stainless is OK, provided it does not vibrate nor flex, else it will probably eventually fail.

Driving 200 klm on corrugations is an enlightening experience for anything which vibrates or wobbles.

cheerio

Originally Posted by mike48

Hi

making brackets and "things" for a dual battery setup in a vehicle might be better made with mild steel which is not so brittle and has a bit of flex when driving on long corrugated roads etc etc.

I have used aluminium and steel in making accessories, etc and find that it has to be solidly bolted down to avoid vibration and flex failure, even in mild steel.
Stainless is OK, provided it does not vibrate nor flex, else it will probably eventually fail.

Driving 200 klm on corrugations is an enlightening experience for anything which vibrates or wobbles.

cheerio

i went for SS because of the water used here to wet down the roads is pulled from the artesian basin and its salty as buggery, went out to william creek and back the other day, no problems other then a flat tyre.

I just noticed the "Roxby Downs" bit, and I now realise that you probably already know all about vehicle add-ons and road corrugations, and what can happen!!

cheerio