Thread: Metal Tearing

I have also asked for a copy , I need all the help I can get

I have had similar trouble with some steel.
It was that cheap black bar you buy from bluescope and metal land .
I bought it originaly to act as rollers to install my machines.
However I used a bit to make a draw bar for a collet chuck .
It is horrific to turn. It has hard and soft parts in the steel and impurities.
That makes it impossible to find the correct machining data as it is not one type of steel .
Chuck it away and buy some good quality free machining tool steel from Bohler.
I finnished my draw bar but it took 2000 rpm a ceratip insert , flood coolant , light cuts and slow feed with traveling steady support. It still produced a wavy surface in places.

Thanks Retromilling,

I had similar issue with some steel I bought from Robot Trading a while ago both round and square tube ...it was cheaper imported steel and half the price of BHP steel at the time....I made the mistake of trying to work and weld it.......was later told by someone who works for a local steel distributor that generally the quality of the imported cheaper stuff is not worth buying...does not meet ISO standards so it's flogged off cheaper for jobs that don't require tight specs or certain standards........The steel originally referred to in this thread was different - quite old and probably lacked the quality control we now have - who knows what went into the brew 100 years ago..........with the suggestions and help from other kind people on this forum I have managed to get a fairly decent finish by slow rpm, rounding the HSS cuttiing tip and a very slow feed rate....no good with auto feed........wasn't too successful with cutting dry or normal lighter cutting lube it preferred some Hypo 90 gear oil I tried...NOT RECOMMENDED!!!...smelt like #@ap and smoked the shed out - but at least it allowed ribbon swarf more than chips and tears.......usual flammable cautions apply of course.....after that I filed to smooth....no where near mirror, but good enough to use......

I used it to make replacement rods and tool post arms for the lathe, QCTP and some other link arms I needed in one piece......threads are another issue....have patience!...hey, at least I'm using up the scrap bin contents........I did try to make a ball end from a piece.......won't go there either!.

I would suggest that you try a heavier lube than normal (Purists can burn me at the stake!) HYPO 90 worked for me because I had some close by.......I've often used Inox occasionally as well.....but in this case 90 was all I had that seemed to work - apart from the smoke and smell......Lee