Questions about canister Damascus

[Chris Railey]

For those of you who make canister and do not mind sharing, would you give me a run-down of your process. Really what I am after is can size, soak time and how many passes through the squaring dies do you make. Also, if you know some good looking combos to use I would appreciate that as well. Now that I have a press I have to try some out...Thanks in advance.

 

[EdCaffreyMS]

OK..... first, can size is relative to your equipment size. For example, the opening on my welding forge is 10" tall X 4 1/2" wide. I can block up unused height with fire bricks. So, that means I CAN create a "can" with a max 4" X 4" size. Next, my press (Orange Crush) max's out at 80 tons, and has dies that are 8" long X 6" wide..... that means I can "press" a can that is 8" long. So with those two factors, I can create a "can" that is 4'X4"x8" long.

When it comes to time in the forge, you have to think in the aspect that ever single grain of powdered steel must reach welding temp. So, that means soak time depends on mass of the "can". For me, using a 4'x4"x8" can, once it appears to be at welding temp..... it soaks a MINIMUM of 45 mins. That time varies depending on the mass of the "can" you are welding/forging.

OK, Passes through the dies is relative. Forging a "can" is more about finesse than brute power. EVERY pass through the dies/press should be done gently. The initial weld/pass through the press is usually NO MORE than about 1/2"..... and that's rotating the billet 90 degrees with each "press". That initial pass through the press is the ONLY ONE that I press the entire billet. It's very easy to get over zealous and try to use all your press has.....all that gets you is a train wreck of distortion that you cannot recover from!
Subsequent passes through the press for me are usually not more then 1/4" bites...... DO NOT try to press/reduce a can billet all at once! It's just like eating a elephant...... ONE BITE AT A TIME! Even on my largest cans, I never try to "take the billet down" on dies larger than 1 1/2" wide..... in other words I am only compressing 1 1/2" of the can at a time/bit. That's how you keep consistent and minimize distortion.

Let's talk squaring dies...... BE CAREFUL..... if you press too much and "roll" the corners....you just created voids at the corners, that you will not recover, and that will have to ground/machined away.....essentially make your end billet smaller. It's FAR better to have squaring dies that are only 2-3" long, and take "bits"........ I have/use both long and short sqauring dies for each size..... mine start at 3 1/2" square, then to 3", and down to 1", in 1/2" increments. I also have 3/4 square dies for special purposes.....mostly for creating bars for composite billets.

Sometime building a "can" is the most time consuming part of the process. IF you prepare the can properly, and with care to remove ALL the airspace, and weld the "lids" on correctly, things always work much better then if you "throw" it together......which generally ends badly.

The trick to "lids"....is to make them out of AT LEAST 3/8" thick material (I often use 1/2"), and to take the time/effort to make them fit INSIDE the can......then, one they are fitted, fill the perimeter with the same powder you used inside.....and THEN weld the lid in place. If you use thin (such as 1/4" the ends WILL pop off the can when pressing, and you watch all that $$$$ go dribbling out.

OK.....HERE IS A HUGE ONE...... BEFORE you weld a lid on a can...... have your forge running, and up to temp, ready for the can. Why? When you weld on the final lid, you are heating things up. IF by chance your welds leave even a tiny pin hole, as the welds/can cool, it will suck atmosphere into the can, and you WILL have a void in that area. So, forge running and to temp.....and as soon at that lid is welding in place.....into the forge!

Finally.... and take it for what it's worth to you. DO NOT TRY TO USE TONGS when forging cans. It's one more thing to manipulate, and to trip you up. Weld a HEAVY handle to the can (another reason for thicker lids). I tend to use 1 1/2" or 2" dia rebar scraps for handles. Very often a lighter hand will "break" during forging and then you're hosed! Have fun!!!

 

[BossDog]

Ed does a good job covering much of the process.

start with a 2x2 can or even a 1.5x1.5". It's expensive to learn on 3x3 if you mess up.

I use a 3x3 can .125" wall thickness. I also make sure the lid fits inside the can when welding. I weld a 1.5" stick on one end to grab it.
My press is 20 tons and can handle the 3x3 but I'd like more.

Oversize dies are better than undersize. Make a few different sizes.

Most of the time I don't worry about removing the can after forging. I just leave it and mill or grind off any remaining can later in the process - if ever.

Soak time is probably in the 15 to 20 minute range depending on your forge. I wait until I see the outside start to look wet. This is bright yellow to starting to turn white. You can squeeze a can too early and it will crush but the inside will sort of tear into rips and clumps. Rotate the can frequently to distribute heat.

I am assuming you are going to add powder. Vibrate the can to get the powder to settle in and fill any voids. I set it on top of my bowl tumbler briefly to get it to settle. The can must be packed. No empty space.

I have had a can pop when squeezing with no vent hole. It did spurt a bit. Wear PP gear. Normally I put a 1/16" hole in one end and super glue it shut. It will shoot out powder a bit but not that much. Put the hole near the top edge when you put it in the forge so it doesn't leak out like an hour glass. After one squeeze or even before, the powder will stop shooting out.

 

[Chris Railey]

Thanks guys that will get me started. I do not mind learning on my own but I like to start in the park at least. I actually planned on using 1.5 x 1.5" cans to get my process down then later I will try bigger. I have some clean 15N20 cutoffs I will use for the first can. I also have some cable which I can break down into the smaller bundles and clean up to use in another can. I am also going to do some San-Mai but I have done that many times before all by hand this will be a first with a press.

 

[EdCaffreyMS]

Another VERY important thing that I neglected to mention...... I have learned over the years that even with a properly prepared "can", expect to reduce it by AT LEAST 50% to achieve a solid end product. So.....going with that notion, if you start with a 1.5" can and reduce it by 50%..... that leaves you with a 3/4" X 3/4" end product..... then you have to either grind or mill off the can.... so you could actually end up with a only a 5/8" square..... and considering that most "cans" require accordion folding...... ya just ain't go much left.

One of the best things about me being able to work big cans, is that by the time I have a 4"x4" starting size down to 1 1/4- 1/12" square, the can has been stretched out into almost paper thin. If I'm careful about squaring the billet prior to annealing, I can clean up whats left of the can, with a single pass on the mill.

OH!!! Something else...... I mentioned the size I usually take my cans to...... here's another tip. The ending size (square) of your billet/can, should be approx the WIDTH you want your accordion/finished billet to come out.....plus whatever you think is necessary to eliminate the can. ITS ALL GOTTA BE GONE! Nothing worse then finishing a blade, etching, and THEN find a big old blob of "can" still there.

 

[Chris Railey]

Another VERY important thing that I neglected to mention...... I have learned over the years that even with a properly prepared "can", expect to reduce it by AT LEAST 50% to achieve a solid end product. So.....going with that notion, if you start with a 1.5" can and reduce it by 50%..... that leaves you with a 3/4" X 3/4" end product..... then you have to either grind or mill off the can.... so you could actually end up with a only a 5/8" square..... and considering that most "cans" require accordion folding...... ya just ain't go much left.

One of the best things about me being able to work big cans, is that by the time I have a 4"x4" starting size down to 1 1/4- 1/12" square, the can has been stretched out into almost paper thin. If I'm careful about squaring the billet prior to annealing, I can clean up whats left of the can, with a single pass on the mill.

OH!!! Something else...... I mentioned the size I usually take my cans to...... here's another tip. The ending size (square) of your billet/can, should be approx the WIDTH you want your accordion/finished billet to come out.....plus whatever you think is necessary to eliminate the can. ITS ALL GOTTA BE GONE! Nothing worse then finishing a blade, etching, and THEN find a big old blob of "can" still there.

Well to the mill supply place I go. Thanks again, that more than likely saved me from some 3/4 inch square billets.

 

[Chris Railey]

I have a friend with a sawmill so I have a decent supply of used mill blades which may make a cool pattern if I can pull it off eventually.

 

[EdCaffreyMS]

I suspect you're gona go down "The Rabbitt Hole"....... as most of us do. Even after all these years of building cans and mosaics, my mind still jumps around sometimes like I have ADD.

The possibilities are endless..... if you can think it, it can be make in steel/a can. I went through a period of time for nearly 2 years where I think I might have made 8-10 knives..... all the rest of my time was spent making ranchers' brands in mosaic/cans, and then making everything from belt buckles (made a BUNCH of those), to pendent and earring jewelry, to Mosaic Damascus conchos for saddles/halters. Why? Because for their brand in a belt buckle these people were willing to pay just about anything I'd quote! I once made one for a worker at Hank Williams Jr ranch...... fairly intricate design, but nothing too terrible...... after drawing it up and showing it to the individual, before I could even quote a price, he pooped off and said...... "WOW!! That's about $2,500 worth!" OK..... so it is. Doing that kind of work had far better margins than knives...... usually the steel required for a single medium knife blade, would produce 1-2 belt buckles, and several smaller pieces for jewelry........ and even that was crazy...... the gals were willing to plop down BIG bucks for the ranch brand in earrings!

OK, gabbing aside, think of building a can, kinda like a puzzle..... only REALLY deep. I have successfully used super glue to hold piece together in a can....at least until the powder fills in a wedges thing in place, but you can also tack weld pieces....but do it on the ends, which you will have to cut off/waste later. Speaking of waste...... be prepared, when building a can, and getting into usable blade stock (that means accordion folding), expect about 70%+ waste/loss. That's one reason it so costly in it's finished barstock state. After I discovered "Fossil" Damascus, where I use the "triangles" cut from accordion folding a billet, that waste has dropped some....to about 50%. Why so much? Well, expect to loose several inches of a finished can on each end, the materials that is milled/ground off when cleaning it up, and all the saw swarf from accordion cutting. And of course, there are always those billets that just refuse to NOT have a void or crack somewhere, and you end up with 1/2-3/4 of it in the scrap pile.

Again..... have fun with it! It's an awesome journey!!

 

[Chris Railey]

I suspect you're gona go down "The Rabbitt Hole"....... as most of us do. Even after all these years of building cans and mosaics, my mind still jumps around sometimes like I have ADD.

The possibilities are endless..... if you can think it, it can be make in steel/a can. I went through a period of time for nearly 2 years where I think I might have made 8-10 knives..... all the rest of my time was spent making ranchers' brands in mosaic/cans, and then making everything from belt buckles (made a BUNCH of those), to pendent and earring jewelry, to Mosaic Damascus conchos for saddles/halters. Why? Because for their brand in a belt buckle these people were willing to pay just about anything I'd quote! I once made one for a worker at Hank Williams Jr ranch...... fairly intricate design, but nothing too terrible...... after drawing it up and showing it to the individual, before I could even quote a price, he pooped off and said...... "WOW!! That's about $2,500 worth!" OK..... so it is. Doing that kind of work had far better margins than knives...... usually the steel required for a single medium knife blade, would produce 1-2 belt buckles, and several smaller pieces for jewelry........ and even that was crazy...... the gals were willing to plop down BIG bucks for the ranch brand in earrings!

OK, gabbing aside, think of building a can, kinda like a puzzle..... only REALLY deep. I have successfully used super glue to hold piece together in a can....at least until the powder fills in a wedges thing in place, but you can also tack weld pieces....but do it on the ends, which you will have to cut off/waste later. Speaking of waste...... be prepared, when building a can, and getting into usable blade stock (that means accordion folding), expect about 70%+ waste/loss. That's one reason it so costly in it's finished barstock state. After I discovered "Fossil" Damascus, where I use the "triangles" cut from accordion folding a billet, that waste has dropped some....to about 50%. Why so much? Well, expect to loose several inches of a finished can on each end, the materials that is milled/ground off when cleaning it up, and all the saw swarf from accordion cutting. And of course, there are always those billets that just refuse to NOT have a void or crack somewhere, and you end up with 1/2-3/4 of it in the scrap pile.

Again..... have fun with it! It's an awesome journey!!

Thanks Ed, I appreciate all the advice. I am sure it will be a journey, I have already thought about multiple patterns or combos...maybe I need to start making notes...