Heat treated or just stamped out?

[tosh]

I'm curious to know if the tools found on the mp400/600 are heat treated or just stamped out, cleaned up and shoved in!

Obviously the blade is I guess - but what about the rest??

Anybody know??

[neillcurrie]

Well, I just put three strokes of the corner on a Leatherman diamond file to my MP400. The screwdriver tang and the blade tang were hardly scratched, but just one stroke of the file on a hard-to-see area of the handle was quite visible.
I say the tools are heat treated.
I just repeated the same test on a Victorinox can opener blade, which seems to be a tad harder than the MP400 tools.

[lowtech]

Always someone there daring to explore something and even sacrificing his tools.  Thanks for the test!

[tosh]

Well, I just put three strokes of the corner on a Leatherman diamond file to my MP400. The screwdriver tang and the blade tang were hardly scratched, but just one stroke of the file on a hard-to-see area of the handle was quite visible.
I say the tools are heat treated.
I just repeated the same test on a Victorinox can opener blade, which seems to be a tad harder than the MP400 tools.

Thanks 
Didn't mean for you to carry out a physical test - just thought someone may have read about Gerber's manufacturing process.

So, it looks as though they ARE heat treated then.

[neillcurrie]

Always someone there daring to explore something and even sacrificing his tools.  Thanks for the test!

I tried the bite test first, like Nadal (he does that to verify the authenticity of every trophy he wins), but decided that a full canine test would be too expensive.

[Gareth]

As I've chipped the corner off the small screwdriver on my MP400 I can attest to them being heat treated.   Would have bent if it wasn't.

BTW, I don't mean this as a criticism of the screwdriver, I was being a plonker and was over doing it on what turned out to be a VERY stuck screw.   I've done the same to a Letterman as well.

[tosh]

Okay, so now my next question.....

To heat treat, I understand you need to heat it until a magnet no longer sticks. Is that correct?? Is it then quenched in oil??? or water 

But I guess if it's stainless, the magnet test won't work.....Doh!! 

[neillcurrie]

To harden: heat till red hot, then quench to cold.
To temper: best to clean an area of the hardened tool first, then heat slowly till the color changes to the desired shade, then quench quickly to cold.
http://en.wikipedia.org/wiki/Tempering_%28metallurgy%29

BTW: I suspect some Gerber tools have questionable hardening/tempering, as do some SAK's. I renovate several old and abused tools and knives, and see a lot of twisted or bent drivers. That seldom happens with a decent Snap-On screwdriver, for example, no matter the abuse (within somewhat reasonable limits of course).

[dks]

i am sure they are heat treated.
To heat treat metal you heat it until a magnet stops working on it but the important bit happens after. How you cool it will affect the heat treat. Tempering will really affect the heat treat. What metal you started with will also affect the heat treat.


A non heat treated metal will be too hard or soft and bendy.

I started a thread about knife making a while back (edged forums?) that has some information on that.

[neillcurrie]

Okay, so now my next question.....

To heat treat, I understand you need to heat it until a magnet no longer sticks. Is that correct?? Is it then quenched in oil??? or water 

But I guess if it's stainless, the magnet test won't work.....Doh!! 

My MP400 attracts a magnet, both the handles and tools, strongly.

[Gareth]

Yeah, some stainless steels are non-magnetic, but it's far from universal.

[dks]

you can buy special SS fridges for fridge magnets which are magnetic

Remember, once the metal cools again it does become magnetic again.

[tosh]

OK, all hypothetical.....

Let's suppose I were to fashion ideas from steel plate - I don't know the type of steel it is I often hear the platers refer to it as"Chromweld"?? Thickness varies from 1-6mm. Although work does have 4 massive laser beds, latest will cut 1" plate !! The running costs are astronomical. So any ideas I have will have to be cut by hand. The engineering shop will I'm sure machine me a few bits should I need them and the tig welders I know are all only too happy to help.

I was just curious about the heat bit.

What's the simplest (cheapest/quickest) method of heat treating thin steel plate?

Lets all assume I know and own nothing.

[zoidberg]

FWIW (which is probably very little) I used a gas torch and water to heat treat a Leatherman Removable Pocket Clip. It's been a few months with heaps of use and no problems with it.

[Syph007]

Im sure they are heat treated, but that is a very generic term and heat treating crappy steel wont turn it into great steel.

In the old days where there was no stainless it was straight forward to heat to color and quench DIY heat treat steels.  Stainless steels need much higher temps and soak times with very narrow margins for error when those domains in the metal are reforming.  Some types require very cold tempertures too (cryo) which is why most blade makes send out stainless blades as its very hard to do at home.

[Steinar]

OK, all hypothetical.....

Let's suppose I were to fashion ideas from steel plate - I don't know the type of steel it is I often hear the platers refer to it as"Chromweld"?? Thickness varies from 1-6mm. Although work does have 4 massive laser beds, latest will cut 1" plate !! The running costs are astronomical. So any ideas I have will have to be cut by hand. The engineering shop will I'm sure machine me a few bits should I need them and the tig welders I know are all only too happy to help.

I was just curious about the heat bit.

What's the simplest (cheapest/quickest) method of heat treating thin steel plate?

Lets all assume I know and own nothing.

Step 1: Download the data sheet for the alloy in question from the steel foundry's web site. This will contain the correct temperature graph (temp vs time) for a proper hardening and tempering. Then you can try and figure out a process without the proper equipment.

[Steinar]

Example of tricky heat treating process: http://www.uddeholm.com/files/PB_Uddeholm_vanadis_4_extra_english.pdf

Example of comparatively forgiving heat treating process: http://www.simplytoolsteel.com/A-2-tool-steel-data-sheet.html

The most expensive knives I own, are expensive partly because of their heat treatment process.