Foil frustration!

P

psriley

Joined
Dec 15, 2005
Messages
26
Apologies if this is a tired topic, but I can't seem to make the search function work. Does anyone have a favorite effective method for quickly getting a blade out of the inconel foil after hardening? Seems like no matter how I pack the blade, I can't seem to get it out foil before it cools significantly.

Thanks,

Pat Riley
 
how are you quenching?

for plate quenching, I just do it in the foil until it cools to the touch.
 
I'm using mostly 1095 steel so I've been oil-quenching. I'm shooting for a quench temp of +/- 1500, but by the time I get the foil open, fumble around getting a grip on the blade and getting into the quench, I've lost the critical temp.

Any suggestions appreciated..

Rgds,

Pat Riley
 
Try folding it in a certain way, so when you take it out the oven the tip is facing down and there's some space between the fold and the blade, then using some large tin snips cut the foil, a sharp jerk, and the blade should drop into the quench tank. I use a wire mesh "catcher" which prevents the tip from hitting the bottom of the tank and getting damaged. I also raise and lower this wire basket in the quenchant (trans fluid) while the blade cools. Good luck!
 
Thanks for the replies. I like the idea of the oversized envelope and the wire catcher. I'll give that a try.

I also thought about just running a piece of wire thru the lanyard hole and using it as a grab handle to yank that sucker out of there.

Cheers,

Pat Riley
 
As an alternative method I have had very good luck using PBC coating. Use the search function and read every thing you find and I think it will convince you to give it a try. PBC gives you the ability to do edge quenching easilly. As to finding PBC Brownells sells it in small amounts at not to bad a price.
 
1095 has such a steep cooling curve that any time you spend between oven and quench is likely to be a problem.
If you don't mind me asking,why are you foil wrapping 1095 ? There is no need to do it that I know of. If any scale or decarb is your aim,a dip in turco,or a PBC coating will do that better ,cheaper, and won't affect the quench time .
 
I got the search function to work last night, and did some reading on the PBC coating. I think I'll give that a try. It seems like a good alternative to foil.

No particular reason I've been using the foil...guess I didn't realize how simple (in theory) the PBC is.




Thanx,

pr
 
Most makers don't use anything on their simple carbon steels.PBC or Turco (that's what I use) will take care of any worries about scale.
 
Yeah, I'm going to pick up some PBC. I fired a blade today just bare, no foil, no nothin. It was fairly scaly and black, but didn't take that long to clean up. But at least I know it was at the right quench temp.


I've got some D2 on the way from tool-and-die, and I think I'll give plate quenching a try as well.

Cheers,

pr
 
Definitely go with the PBC or Turco. It's impossible to take a foil packet off of a blade and get it into the quench in less than one second, which is required to get 1095 to harden. I had to modify my quenching setup to get from the fire to the quench quickly enough to harden 1095 without any other time consuming issues, like a foil packet for instance.

You could just quench the bare blade and clean up the scale/decarb. afterwards, or you could try Japanese style differential hardening and make those georgeous hamons.


Todd
 
I use turco for any oil quench steels -just because I can't get them out of the foil fast enough. Anything air quenchable gets plate quenched still in the foil. Can't beat it! Foil rocks! (except for rusty steels) ;)

Rob!
 
Well, I picked up some PBC powder from Brownell's and fired a high-carbon blade with it today. I got mixed results, but they were encouraging. The places where the PBC covered came out fairly pristine...just a slight discoloration. There were some spots, though, that I guess didn't quite get covered, because I ended up with scale where I didn't really want it. I read in another HT thread where someone applied a second coat of the stuff after soaking the first coat for a few minutes...I think I'll try that next. Overall, though, this seems like a good alternative to foil. I got from oven to quench very fast, and ended up with only a little cleanup on the blade.

Cheers,

psr
 
May I ask what type of quenchant you are using? I went to Brownells Tough Quench finally. It seems very clean and hardly any scale. Also I use a close ended pipe in the forge to heat my blade in. There is no air blast or flow inside the pipe. As we all know that air is the scale builder and if we can reduce the amount of air on the steel the less scale we will make. Another advantage of the pipe is a very nice even heat.
 
After I got the bit of scale cleaned off the blade I had coated with PBC, I saw there was some pretty significant pitting after all. I've been using corn oil as a quenchant, and using an old army ammo can as a quenching tank. The can holds about a gallon of oil. The corn oil is a fairly light, so I had thought it quenched pretty evenly and quickly, but now I'm wondering if I should try a different quenchant myself.

I'm also going to give the PBC another shot. Wherever it did cover the blade was really clean. I think I just needed to be more thorough in applying it.

Using a small Paragon oven to do the actual firing.

I think I'm also going to try a couple of blades with D2 and give plate quenching a go. Seems like a much cleaner process, and maybe a bit less hazardous. That corn oil does tend to flare up :eek: .


Cheers,

psr
 
Make sure the blade is nice and clean before applying the PBC. Washing
with dishwashign soap, etc. I find that "Bartender's Friend" cleaning powder
is nice for it. Almost anything will do. Clean to point where water doesn't bead up - this is when you know it is clean. Dry it off.

Heat the blade up to about 450F, use a fine sifter from your friendly food supermarket and shake the powder over the blade, both sides, making sure
you cover it well. If the powder bubbles up into largish bubbles, the blade's
too hot. It should sizzle a bit, but stay nice and flat. Some folx apply powder
twice, with a short ~500F stay in the oven in between.

Shake the powder over a piece of common kitchen foil - this way you can collect and reuse the excess powder.

Most of PBC covering will come off during the quench. Whatever is left, just
put the blade into $1 plastic container from Lowes and pour some boiling water over it.

It sounds a bit evolved, but it aint. It all works 100%. But you have to be
pretty thorough about it - if it pits in a wrong spot, it will be a PITA to remove it. And sometimes it just might ruin a blade if there's no "safety" metal to be removed . So leave some extra meat just for that.
 
Yeah, I haven't been doing much cleaning of the blades prior to HT, but it makes sense to do that. I'll be doing that from now on as well.

Unfortunately, the pitting on this particular blade was too deep in the wrong places, so it won't be leaving the shop.


Cheers,

psr
 
Am I missing something? Doesnt everyone have to do their final grinding after HT? Arent you leaving meat on the endge prior to HT? Ive never had pits from scale any deeper than whats required for me to grind off anyways in my final finishing.....ive never bothered with much anti scale or anything because I am going to need to grind afterwards anyways....

What am i missing here? Tang cleanup? ricasso? Whats the bang for the buck?
 
For me it's just the hassle-factor. With the PCB you never have to deal with scale - at all. There just isn't any. That's nice! Why use up belts grinding scale when you don't have to?

-Ben M.
 
I guess it's just a matter of what you consider final grinding. Ideally, I'd like to take a blade straight from heat treat, shwack it with a couple of passes on a scotchbrite belt, or hand-rub a finish, and be done with it...ready for a handle and cutting edge.

Unfortnately, that didn't quite happen with this particular knife, but I see the potential for the PBC to work quite well. This particular knife, it was the pitting that made it a sub-optimum piece, and the pitting may be due to something else. Although, I finished it this evening and I kinda dig how it turned out anyway, warts and all.

I'm just a hobbiest at this point, but I can imagine in a production environment, saving time on finish grinding make a big difference in terms of order backlog.

Cheers,

psr
 
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