Why use white-out on canister damascus?

[Tom Lewis]

Over the past several months I have made a number of blades out of canister Damascus. On Forged in the Fire I notice most smiths use white out and then try to pry the can off the billet. I really think there is a better way.
Why worry about taking the can off? By the time the canister is forged out the can will be very thin and will grind off when the knife is made.
Taking the can off after the first heat can cause problems. If the powder in the can has not become solid the billet is wasted. If the can is left on and brought up to more welding heats the powder in the can has a much better chance to become solid.
I have never used whiteout and never tried to take the can off. I have had 100% success.
I also have never drilled a small hole in the can before forging.
Where did the whiteout idea come from? I think it is a case of someone saying that is the way to do it and then others just accept that that is the way.

 

[12345678910]

J Neilson - the judge on the show has a youtube video of it.

Variations are Yellow Ochre, or stainless foil.
It works best when it can dry, which is impossible on the show.

They all do it trying to show that they have watched the videos and as a suck up to him.
I think it's mostly done by those with no canister experience.

Those that I've seen do well on the show do exactly what you say, weld, weld and weld again then grind it off or leave it as a cladding layer.

 

[Natlek]

Mild steel is hungry for carbon ? Probably White will stop migration of carbon on can and easy to take the can off after welding .Leave it /mild steel canister/ to the end of forging probably will pull a lot of carbon ...just guessing ?

 

[Tom Lewis]

12345678910, I think you have showed the reason why people use white out. J. Neilson does it so that must be the right way.
Well, anyone is free to use whiteout, but I think they are wasting their time and even causing bad results in that they don't give the billet a chance to completely weld.
I think there are three factors in successful canister Damascus. 1. get the powdered steel in all the recesses and crevices. Completely fill the can with powder. I preferer a canoe canister because I think it is easier to fill with powder. 2. Leave the can in the forge long enough at welding temperature. I leave a 2" can in 30 minutes after it appears to reach welding heat. For 1" or 3/4" canister I leave in 20 minutes. This has always worked. 3. Don't mess with whiteout and don't try to get the can off. With a 2" canister I draw it out maybe 30" long. Take a 1/8" piece of steel and draw it out 30" and it will be paper thin. Maybe leave the billet a bit oversize and the can will be ground off.

Something else I have found out is the larger the can is the more distorted the chain will be. The picture in my first post came from a 3/4" can. The picture in this post was motorcycle chain that came from a 2" can.

 

[Larrin]

The white out thing was discussed briefly a couple years ago too: https://www.bladeforums.com/threads/kuraki-on-fif-anyone-else-watch-last-night.1591878/

 

[TheEdge01]

12345678910, I think you have showed the reason why people use white out. J. Neilson does it so that must be the right way.
Well, anyone is free to use whiteout, but I think they are wasting their time and even causing bad results in that they don't give the billet a chance to completely weld.
I think there are three factors in successful canister Damascus. 1. get the powdered steel in all the recesses and crevices. Completely fill the can with powder. I preferer a canoe canister because I think it is easier to fill with powder. 2. Leave the can in the forge long enough at welding temperature. I leave a 2" can in 30 minutes after it appears to reach welding heat. For 1" or 3/4" canister I leave in 20 minutes. This has always worked. 3. Don't mess with whiteout and don't try to get the can off. With a 2" canister I draw it out maybe 30" long. Take a 1/8" piece of steel and draw it out 30" and it will be paper thin. Maybe leave the billet a bit oversize and the can will be ground off.

Something else I have found out is the larger the can is the more distorted the chain will be. The picture in my first post came from a 3/4" can. The picture in this post was motorcycle chain that came from a 2" can.

Cool looking Damascus!!!! I’ve never seen that pattern before.

 

[Tom Lewis]

Larrin, thanks for pointing out the previous discussion on Blade Form on leaving out the whiteout. Maybe that's where I got the idea to leave the can on.

These blades were made from ball bearings in a 2" canister. Next time I use ball bearings I will use a smaller canister. The 2" canister caused the ball bearings to be stretched so far they aren't hardly recognizable.
TheEdge01, thanks for the nice comment.