Need info about lathe bits

[Pooh_Bear]

Last time I ran a metal lathe was when I was in 9th grade.
Well, not quite. I ran a turrent lathe for 2 days at a machine shop a couple of years after HS.
But it has been a few years.

I seem to remember that we used HSS cutting bits.
How can I obtain some of these bits now.
I need a cut-off bit.

Can I just go get some 3/8 square HSS stock and grind it into a lathe cutter?
Or do I need to get actual lathe bits.

I think I read somewhere that old HSS drill bits can be
ground into lathe bit shapes. Is this true.
This would work in a pinch for me but I really need square bits.

I'm trying to design a machine for cutting metal here at home.
Think of a plotter but replace the ink pen with a cutter bit.
It would be great for making highly accurate cuts in small pieces of flat steel.

Thanks.

Pooh Bear

 

[razorback98]

A lathe cutoff tool is made of HSS and it is flat and can be any where from 1/8" to 1/4" thick. It will be straight across the nose of the tool. It will have side clearances on both sides and the nose will be tapered back. There are some cutting tools that you could make from a drill but not a cutoff tool.
I would go to some local machine shop and buy some of their old tools.

If your talking about cutting on your machine you will need something like a router bit for metal in a rotary head.

 

[Pooh_Bear]

I understand grinding the shape of the bit and the relief on it.
Ok, not square. maybe 1/8 x 3/8 ?

Not like a horizontal mill with a rotary cutter.
More like a shaper with a back and forth motion.

Pooh Bear

 

[Bluecheck546]

You may want to check out this site, http://www-me.mit.edu/Lectures/MachineTools/lathe/intro.html
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[MadReferee]

I would post this question on one of the machinist's forums, like The Practical Machinist or the Home Shop Machinist. You will get lots of really good help on either of these forums.

 

[Pooh_Bear]

Thanks for the links. Very informative.
It will take me a while to read thru that first one.

For now I'm gonna assume I get some HSS stock
and grind a parting tool cutter out of it.

Now I'm off to go read.

Thanks.

Pooh Bear

 

[63DH8]

http://www.grizzly.com/products/searchresults.aspx?q=cut+off&submit.x=8&submit.y=6

 

[5030]

Mr. Bear:

I own a machine shop. We make all kinds of custom one off parts and a few production items for the motorcycle indusrty.

Without getting complex here, I'd suggest www.use-enco.com.

I probably buy 90 % of my perishable tooling from them and their parent company www.msc.com.

I don't quite fathom what you are trying to do, the gage of the material as well as the alloy will dictate the cutting tool and whether the cutting tool is drawn across the material to be cut or whether it rotates is all germane to what type of tool and material make up of the tooling itself. Cemented Carbide tooling is cheap and HSS and HSS/Cobalt square and rectangular tool bits are inexpensive too. If you don't remember how to grind HSS and allow for rake and clearance angles, go to insert tooling. Get an Enco catalog, they are free and probably contain everything you need. Grizzly sells some tooling and holders but Enco and MSC have everything.

 

[3RRL]

Look in the phone book for an Industrial tool supplier in town. They should carry all kinds of tool bits, HSS and Carbide. Get the HSS so you can grind the shape yourself unless you have silicon carbide or diamond wheel for the grinder.
I can't picture what your use will be either, but the last time I ran a shaper was 25 years ago. The bit is somewhat like an upside down cut-off tool for the lathe, cutting by pushing only. Maybe you can describe the cutting action your tool requires a little more?

 

[PineRidge]

Bear lately metal lathes are attracting my attention also. I like you haven't operated one since metal shop in high school but for some reason I'm feeling the itch again. Anyway I have seen tons of lathe tooling offered at eBay and some of it at very good prices. Do an eBay search for what you need, you might be pleasantly surprised.