Heat Treating

[MushiSushi]

Having said that, I would have liked to have seen you wearing a full face mask while using the salt pot, even if you have been using them without incident for the last 4 years or so

[MushiSushi]

I've got a few questions for you, Cal;

do you build your own venturis?

did you build the press yourself? (and do the AutoCAD?)

is that salt pot the same one you built 4 years ago or has it had a number of incarnations?

I've enjoyed looking around your photos, some lovely knives.

especially this one;

[jrmy0641]

beautiful knives, Cal

[CAL G]

I've got a few questions for you, Cal;

do you build your own venturis?

did you build the press yourself? (and do the AutoCAD?)

is that salt pot the same one you built 4 years ago or has it had a number of incarnations?

I've enjoyed looking around your photos, some lovely knives.

especially this one;

Simon, to answer some of your questions.
I did design and build my own burners.



I did design and build the press. The auto cad drawing was done by my son. When I graduated engineering we still used slide rules and compters were IBM cards with Fortran programming.

The salt pot is exactly the same with no modifications, in fact I just used it last Saturday.

To me, knife making and forging is about making the equipment as well as the knives. I have been lucky enough to have the welders and lathes to do this.


Here is what Raymond Richard from Oregon had to say about my burners.

Hey Cal,

I just got back with a new regulator and gage. Got the burner hooked up and my first impressions are without having it in a forge that it’s better than the XXXX burners and most likely better than all his burners.
I've got it set at 2 pounds pressure or less and I'm thinking it will be just fine for the type forging I do with the small forges I use. I'm going to change cloths and go give it a test run. I'll let you know what I think after I give it a trial run but I'm thinking I may even be more impressed after I use it.

Ray


Cal,

I did some forging yesterday with the new burner. As far as I'm concerned it’s the best venturi design burner I have ever used. Hard for me to tell exactly how much gas pressure I was running it at but I don't think it was more than 1 1/2 pounds. A local bladesmith was over and he thought it was burning a little rich. He thought I should try a smaller orifice. I went to get the number 60-drill bit I had and found out it was a 57 like you used.

Ray


Thanks for the comments Simon here is a photos of my latest knife picture..

[aaronblacksmith]

does anyone here heat treat in the forge? charcoal/coke etc

[Everything Mac]

some times yes. - but not for knives any more.

I heat treat blades using gas nowadays as I was having too much trouble getting decent even heat.

atb
Andy

[Dave Budd]

when I'm deomnstrating at shows and using my Iron Age or Roman forges for teaching, then yes I heat treat in teh forge (charcoal, back blast). I used to use my coke forge (bottom blast) with a pipe in it to give me a clear space, but these days I use a temperature controlled gas forge ala Don Fogg

[lemmythesmith]

I always heat treat using a forge-got nothing else!! Never use anything other than water for quenching, done three blades in oil in twenty years.

[jamiemackie]

I dont anymore but have done loads of times.

I found the best method for smallish blades is to get a tube and put that in the forge and HT in that, much more even. Also when you put the fuel in make sure its small chunks no bigger than an inch square, too big chunks and youl get an uneven heat plus if your using clay big bits will pull of the clay which is very very annoying.

Jamie

[Stuggi]

Has anybody tried hardening and quenching of a blade in the same heat? I read in some old book on blacksmithing that hardening and tempering could be done by first heating the steel to non-magnetic, then quenching only the edge in oil/water. After that the quenched edge is quickly polished so the oxide colours can be seen and heat is allowed to creep from the still quite hot spine into the edge. When the proper temper is achieved the whole blade is quenched and swirled in the quenching medium. I've never tried this, but it sounds a bit quick and dirty to be honest.