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Daddy3x
17th July 2009, 09:44 AM
I feel the need to pick up a bar of HSS and making a skew scraper for the outside of bowls. What might the "industry" numbers/names I am looking for? I am thinking of grinding a tang and turning a handle and such. It may be cheaper to just buy one, but what fun is that?

RETIRED
17th July 2009, 10:55 AM
I use Bohlerit for my skews but a scraper needs to be thicker than the 6 mm I use.

http://www.buau.com.au/english/b_2265.htm

I think McJing has some hss as well.

Edit: Oops, just saw your address.

rsser
17th July 2009, 11:35 AM
If it's a spear point scraper then I'd say 1/4 would be enough.

Check your local industrial supplies place and see what they've got in HSS.

Bigger US turning gear suppliers might have steel blanks in 1/4 x 1 or 3/4.

Ed Reiss
17th July 2009, 12:10 PM
Google "hss blanks and bars" and also try "M-2 steel"

You should get plenty of hits.

Good Luck:2tsup:

Paul39
19th July 2009, 08:53 AM
Go to your local machine shop and ask if they would sell you any HSS off cuts or "drops".

Talk to a knife maker about where to find steel.

On page 815 of the Enco catalog starts a discussion of steel.

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=619-1900&PMPXNO=16719657

If you do not buy prehardened steel you will have to heat treat your scraper, a knife maker can do that for you.

I looked into doing the same thing some time ago and found the steel blank was $30 - $40.

I have since bought a box of junk at an auction that contained two 1/4 X 2 X 15 inch pieces of steel with "knife steel" written on them. Most likely carbon, but with a slight arc across the front and about an 80 degree bevel, they sure smooth things off.

I give the scraper a little swipe on the grinder & leave the little wire edge burr on the top.

I use it angled down from the rest, touching the piece below the center, just barely touching, so I get a little whisper of sound and dust or tiny bit of shaving.

I don't even have a handle on them.

Daddy3x
19th July 2009, 01:37 PM
I know exactly where I am going to stop by on the way home. Should have thought to ask about scraps. In the past I had asked for some square tubing to be welded up for the legs under the lathe, guy just asked for a bowl, I took him several and a few pens as well. He was thrilled. He said he was real clumsy with wood, but an extremely talented machine shop owner/operator.

So, if not HSS, a blank that is heat treated should suffice? Coincidentally, there is a heat treating shop next to the above machine shop :U

Paul39
19th July 2009, 02:15 PM
Read this about hardening:

http://www.use-enco.com/CGI/INPDFF

M2 is used for lathe tools. Most tool steel is shipped in unhardened condition so that it can be shaped by mills, lathes etc. After hardening and tempering it is ground.

The hardening process gets the tool hard and as brittle as glass, then it is tempered to take away the brittleness so that it does not shatter or break off if you get a bad catch. The tempering gives you a range of hardness.

There are ways to do this at home, but it is better to have a controlled furnace, pyrometer, etc.

If you can swap bowls for machining and heat treating, you are set for life.

Let us know how it turns out.

BobL
19th July 2009, 02:30 PM
Read this about hardening:

http://www.use-enco.com/CGI/INPDFF

M2 is used for lathe tools. Most tool steel is shipped in unhardened condition so that it can be shaped by mills, lathes etc. After hardening and tempering it is ground.

I have bought stuff from Enco and their M2 is all pre hardened. Enco M2 pieces are really sized and shaped for metal working lathes and I find they are not long enough for a decent size scraper.

BTW Unlike 0 and A type tool steels, hardening and tempering M2 is well beyond the average home shop.

hughie
20th July 2009, 12:46 AM
Unlike 0 and A type tool steels, hardening and tempering M2 is well beyond the average home shop.

True, as well Bohler have upped their prices some, might as well order from Mcjings they will post Australia wide. Their M2 is a bit ordinary, but at the price I don't think anybody else comes near.