High Speed Steel?

This topic has 21 replies, 16 voices, and was last updated 11 May 2017 at 08:39 by Michael Gilligan.

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8 May 2017 at 20:09 #297177
Vic
Participant
@vic
I've been trying to source some 8" long bits of 1/4" round HSS and saw this:

**LINK**

6.5 mm is close enough although it does go on to say it's .25"

I nearly ordered some until I also noticed it say it's unhardened. I've not seen unhardened HSS for sale before and got the impression it's not really possible to harden it in the home shop properly. Any ideas of where I can get some 8" long pieces of 1/4" HSS that's ready to grind?
Advert

8 May 2017 at 20:09 #18510
Vic
Participant
@vic
8 May 2017 at 20:21 #297181
Roger Provins 2
Participant
@rogerprovins2
Search eBay "round bar 200mm hss"
8 May 2017 at 21:05 #297193
David Standing 1
Participant
@davidstanding1
Also look for HSS drill blanks. You'll have to look for long series if you need 8" length.
8 May 2017 at 21:32 #297202
Vic
Participant
@vic
Posted by Roger Provins 2 on 08/05/2017 20:21:14:

Search eBay "round bar 200mm hss"

I tried that and the only hit was unhardened again.
8 May 2017 at 21:47 #297204
Nick_G
Participant
@nick_g
.

I cannot help you in your search quest. – But curiosity has got the better of me. What's it for.?

Nick
8 May 2017 at 21:59 #297209
Vic
Participant
@vic
Posted by Nick_G on 08/05/2017 21:47:26:

.

I cannot help you in your search quest. – But curiosity has got the better of me. What's it for.?

Nick

Wood turning tools. I've found and ordered some 10mm X 200mm for £2.44 a piece inc shipping but can't find any 1/4".
8 May 2017 at 22:11 #297213
John Stevenson 1
Participant
@johnstevenson1
What about 1/4″ Stellite?
8 May 2017 at 23:09 #297222
Clive B
Participant
@cliveb55652
You can purchase 6.5mm x 200mm HSS from CTC Tools, but they only seem to sell this size in packs of 5. By coincidence I have also been trying to source long pieces of HSS for woodturning tools.

Clive
9 May 2017 at 02:11 #297234
peak4
Participant
@peak4
Here's some 6mm in China

**LINK**
9 May 2017 at 13:20 #297289
Vic
Participant
@vic
Posted by peak4 on 09/05/2017 02:11:32:

Here's some 6mm in China

**LINK**

Thanks, I've found another seller on eBay with some 6mm so I've ordered some but I'll bookmark that one as well.

I've seen some 30" lengths of 1/4" in the US but it's not cheap and of course the postage would be silly money.
9 May 2017 at 13:33 #297295
Neil Wyatt
Moderator
@neilwyatt
Well unhardened HSS is like hen's teeth but I suspect that seller may actually have silver steel…

Neil
9 May 2017 at 14:14 #297304
John Haine
Participant
@johnhaine32865
IIRC, Martin Cleeve's book on screwcutting in the lathe has instructions for hardening HSS.
9 May 2017 at 16:05 #297322
Neil Wyatt
Moderator
@neilwyatt
The problem is that there are many versions of HSS and as many different treatment procedures. It would be nice to know what version of HSS they were using in the 50s/60s that could be treated adequately by heating white hot, then quenching with an air blast.

Neil
9 May 2017 at 19:25 #297335
Nigel Bennett
Participant
@nigelbennett69913
I recently got some of the 6mm round HSS from China; I needed them for making some taper reamers for making injectors. I was quite surprised when one of them twisted in use, ending up looking like those olivers they put on showman's engines. So having realised they were unhardened, I simply heated the end of one of them up to cherry red and dunked it in some water. A gentle tap with a hammer had the hard end pinging off into the recesses of the shed, so at least it confirmed they were hardenable!

**LINK** gives some useful information about hardening & tempering HSS. I shall have a go and see what I can do with the Chinese HSS and then make some more reamers!
9 May 2017 at 19:40 #297336
David George 1
Participant
@davidgeorge1
To check the type of steel the sparks given off by HSS is different to silver steel when ground on an offhand grinder. Use a known sample as a guide. A red spark with HSS a brighter spark with silver steel. I was taught this as an apprentice.

David

Edited By David George 1 on 09/05/2017 19:42:18
9 May 2017 at 21:07 #297354
Ian Welford
Participant
@ianwelford58739
get in touch with Ashley Isles , Tony Isles is probably your best bet over in Spilsby. They sell off cuts of the HSS bars they use to make wood working gouge. I ve had a few bits from them to make round skew chisels for wood turning and its excellent stuff.

Also had tools from CTC and they're very helpful too.

Good luck

Ian
9 May 2017 at 23:16 #297374
Jelly
Participant
@jelly
Neil, by the 60’s most grades of HSS had been developed (the landmarks being Mushet steel in 1866, T1 in 1907 & M2 in 1936).

M2 can be adequately treated by heating to 1040-1100?c in atmospheric conditions, followed with a combination of brine quench until equalised followed by air until cool.

M42 will also harden that way, but as it won’t reach its full potential (upto HRC70!!!) without salt or vacuum treatment at temperatures very close to it’s melting point, it would be pointless buying the higher grade to then heat treat it like that.

As I understand it the issue with all HSS is the need for controlled heating for good results… Initally in several stages followed by a rapid burst of energy to take it from ~900?c up to the final hardening temp of 1100-1200?c, and then multiple long tempering cycles in very a narrow temperature band… it would be hard and labour intensive to achieve that without building or buying specialist equipment.
10 May 2017 at 10:49 #297435
Ian S C
Participant
@iansc
For wood turning tools you probably would be best if it was hard and tempered at the cutting end, graduated to the soft state at the handle end. I'v got some HSS wood turning tools, but I have not checked the hardness handle end, but less likely to break if unhardened. Ian S C
10 May 2017 at 15:41 #297477
Neil Wyatt
Moderator
@neilwyatt
Posted by Joshua Kelly on 09/05/2017 23:16:37:
Neil, by the 60's most grades of HSS had been developed (the landmarks being Mushet steel in 1866, T1 in 1907 & M2 in 1936).

Indeed, but what was the grade that contributors to ME were using? They only ever describe it as 'HSS', but the characteristics were machinable with ordinary tooling and hardenable with a two step process of heat and air quench.

Neil
10 May 2017 at 18:41 #297497
Anonymous
Probably D2, a high carbon and chromium tool steel that can hardened, air cooled and tempered in a similar manner to gauge plate, albeit the hardening temperature is rather higher at about 1000°C. That's perfectly doable in the home workshop whereas the 1200°C required for full hardening of HSS is not.

Andrew
11 May 2017 at 08:39 #297576
Michael Gilligan
Participant
@michaelgilligan61133
Posted by Neil Wyatt on 10/05/2017 15:41:14:

Indeed, but what was the grade that contributors to ME were using? They only ever describe it as 'HSS', but the characteristics were machinable with ordinary tooling and hardenable with a two step process of heat and air quench.

.

Caveat lector

MichaelG.
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