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PBC


guarnera
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Well I screwed Up, I was normalizing my blade. The first time using the electric furnace and PBC from Brownells. I thing its PBC. That or PCB.Anyway I coated the blade as described, put it into the 1600F furnace, waited for it to return to 1600F and soaked it for 10 min, removes and let air cool. Now hears were I screwed up. Thinking I could save time I recoated the blade before it cooled down all the way. Heated to 1575F no soak and air cooled. Well I should have washed the blade and put a new coating on it because the first coating started to flake off in spots. I ended up with spots on the blade with what looks like a combo of scale and PBC. Its real hard and etched into the blade. It also looks like it ran off the edge as I have the same issue all along the edge. I put the blade in edge up. I'm not sure if the edge thing happened on the first heat or the second. I've almost got one side all polished out again, but I'm afraid to use the PBC again even just one heat per coating. I can put the blade in edge down, but the blade has a false edge at least 3/4 the length of the blade. I'd hate for it to run off of that and screw it up again. I know the first time was my fault for trying to rush things. Has anyone else used this stuff? Will it still protect the top edge of the blade if it runs a little? I will wash the blade and recoat before reheating this time. But I'm still a bit scared. What do you people with electric furnace's do for scale prevention? Help!

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I used it long ago but it usually made more of a mess then it was worth. As soon as I built a blown forge I can get the atmosphere so rich that there is no scaling or pitting.

 

There is always stainless or titanium foil you can use. It's even and won't run.

Everything I need to know I learned from the people trapped in my basement.

 

 

I'm out of my mind but feel free to leave a message.

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I used it long ago but it usually made more of a mess then it was worth. As soon as I built a blown forge I can get the atmosphere so rich that there is no scaling or pitting.

 

There is always stainless or titanium foil you can use. It's even and won't run.

 

 

Thanks B, you've been a big help. I was thinking about foil. Would it bee OK to use foil for at least the normalizing? It should still cool fast enough even in the foil, for normalizing? This is 5160. If that would work maybe I'll take a chance with the PBC for the hardening. What do you think?

 

Thanks.

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  • 2 weeks later...

Venturies are fine for farriers and ornamental blacksmithing but for knives you are just making more work for yourself. We shoot for a nice finished product and have to pay attention to far more variables in the forging and heat treating process. Atmospheric control is absolutely vital to avoid many wild cards in the process.

Everything I need to know I learned from the people trapped in my basement.

 

 

I'm out of my mind but feel free to leave a message.

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Venturies are fine for farriers and ornamental blacksmithing but for knives you are just making more work for yourself. We shoot for a nice finished product and have to pay attention to far more variables in the forging and heat treating process. Atmospheric control is absolutely vital to avoid many wild cards in the process.

 

 

Electric furnaces suck too. Good for stainless wrapped in foil, but otherwise, lots of scale. Mr. Finnigan, When taking a blade out of a reducing atmosphere and letting it air cool, do you get any scale on the blade from exposure to oxygen from the time it leaves the forge until the time the blade cools? I'm thinking of converting my Paragon to an inert atmosphere furnace. Thank you.

 

Tony G.

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I give it a slow cool down in the forge with the flame off. For me the scaling only happens while forging. It's during HT after I have done all the finishing work that I want to avoid pitting and scale. And with a blown forge and a neutral to rich atmosphere neither one is a problem. I also preheat my forge until the refractory is orange, all the flame does is maintain the heat. And with a very rich almost yellow flame it's no problem to maintaint eh heat. During the heating phase the atmosphere won't be rich and the heat very uneven. Both are bad news for blades.

 

It's tempting to just fire up the forge and stuff the knife in to get going on HT. With my forge pre-heated most of my blades hit CT within 5 minutes. There really isn't any difference time wise.

 

I just HT'd a 4 lbs hammer last night and gave it a 20 minute soak and had no scale or pitting other then what was already there from forging it.

 

I have no use for PBC, foil etc. It's extra steps with less guarantee of the desired outcome.

Everything I need to know I learned from the people trapped in my basement.

 

 

I'm out of my mind but feel free to leave a message.

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