Sign in to follow this  
Will W.

Canister Damascus questions

Recommended Posts

Hello everyone. 

I've recently acquired a few CV axles from a friend of mine, and while disassembling them for the steel, I came upon quite a few ball bearings, which I quickly snatched up (though I hadn't even considered them prior.) I am now wondering about mixing them with some other little pieces of high carbon steel and doing a canister Damascus knife. I've made Damascus before, but I have never tried this before, so I have a few questions, which I couldn't find answers for, after several hours of searching. I apologize if I overlooked something.

Every time I've seen canister Damascus being made, people use mild steel tubing, with ends welded on. Then they have to go through the trouble of keeping the tubing from sticking to the higher carbon steel inside, and having to peel off the mild can. Why not use high carbon steel and fabricate a tube out of that? And just forge weld it right to everything else? It seems like a good way to circumvent all the problems, in my head at least. I'm curious about how it would affect the final pattern as well. 

I know that grinder swarf is generally pretty contaminated stuff (lots of silicon carbide and aluminum oxide usually mixed in), but if I "filter" it (running a strong magnet by it multiple times) to remove anything but steel, would it be alright to use in the can? I also plan on using filings and the curly bits from around the drill press. I assume these are good to go, since both were made strictly by steel on steel contact.

Lastly, I understand that canister welding needs a good long soak to get everything inside the can up to temp, but I'm picturing actually doing it in my head, and I can't figure out a way to accurately tell when everything is ready. Anybody have a tip or two for telling when the internal steel is all up to temp?

Any help would be greatly appreciated. Thanks in advance. 

 

Share this post


Link to post
Share on other sites

I'll be interested in the answeres offered hear, as I had thoughts along some of the same lines myself and in general came up with similar questions.

Share this post


Link to post
Share on other sites

My uneducated guess for why not to make a canister outside out of high carbon steel is because then I don't think you are going to see any pattern (and that's sort of the point). To see the pattern of the inside you'll need to remove the wrapper. At that point you might as well remove cheap mild steel that was already the right shape vs watching expensive blade steel turn to crud under the whir of an angle grinder.

Share this post


Link to post
Share on other sites
2 hours ago, Will W. said:

I know that grinder swarf is generally pretty contaminated stuff (lots of silicon carbide and aluminum oxide usually mixed in), but if I "filter" it (running a strong magnet by it multiple times) to remove anything but steel, would it be alright to use in the can? I also plan on using filings and the curly bits from around the drill press. I assume these are good to go, since both were made strictly by steel on steel contact.

the one thing is that if the shavings are mild steel, then if that is on your edge....well...then you have un-hardenable parts of the edge and blade. Not good. It would be fine obviously though if you were doing something like jewelry where (most) doesn't need hardened.

                                                                                                                              Littleblacksmith

Share this post


Link to post
Share on other sites
12 minutes ago, littleblacksmith said:

the one thing is that if the shavings are mild steel, then if that is on your edge....well...then you have un-hardenable parts of the edge and blade. Not good. It would be fine obviously though if you were doing something like jewelry where (most) doesn't need hardened.

                                                                                                                              Littleblacksmith

The only steel that sees a file in my shop 90% of the time is hardenable. Im usually filing knives. Even if there is a little mild in with everything else, carbon diffusion will help.

Share this post


Link to post
Share on other sites

ok, good to hear. I just didn't know because you didn't mention it in your original post.

                                                                                                                            Littleblacksmith

Share this post


Link to post
Share on other sites

I meant to, I apologize. The little curly bits from around the drill press are also high carbon.

Lanternnate

I considered that. But I expect once the high carbon can is welded to everything inside, then drawn out, then flattened and shaped into a knife, the pattern will still be visible, no? Maybe not quite as well as with the can removed? I'm definitely not an expert, by the way, so I'm speculating. 

Share this post


Link to post
Share on other sites

The grit off a grinder will have steel embedded in it or vise versa, stuck together anyway. However, I've been keeping a cake pan under the blade on my cutoff band saw. I have a different coffee can for mild, spring and RR rail. I also have a bunch of drill press shavings in a can.

I don't know how much if any effect on pattern the can would have once you did some finish grinding. It is a thought though so forge thick and grind thin. 

Frosty The Lucky.

Share this post


Link to post
Share on other sites

Just a thought...I'd anneal those bearings separately first possibly before throwing it all together in the can.....that might make things "merge" together better when you blend it.

Share this post


Link to post
Share on other sites
12 minutes ago, WOLFJOHN said:

Just a thought...I'd anneal those bearings separately first possibly before throwing it all together in the can.....that might make things "merge" together better when you blend it.

Wouldn't that decarbonize them? How would annealing makes things "merge" better? It all has to come to welding temp anyway.

Frosty The Lucky.

Share this post


Link to post
Share on other sites
12 minutes ago, Frosty said:

The grit off a grinder will have steel embedded in it or vise versa, stuck together anyway.

I had not thought about that. And if there's enough SiC inside that can, it could cause an inclusion, or just inhibit welding. Thanks for the tidbit. 

I'm very interested in what the pattern will look like. Come what may, I'll probably end up making a high carbon can and welding everything together, just to sate my curiosity. 

 

Wolfjohn

I don't believe annealing the bearings will have any effect. After all, they will be up to forge welding temp at some point, so any heat treatment you do to it will be null and void at that moment.

 

Share this post


Link to post
Share on other sites

I would think when drawn out you'd basically have a San mai with the Damascus in the middle and your carbon steel as the jacket. If that's the case you're only going to see some of the pattern towards the edge from where you grind the bevels. Now when forging and drawing out there is also a good chance everything doesn't just stay nice and square and in line and you might have some "squeeze out" type things happening. Then you might see more of the pattern, but that would be unpredictable and still just be splooges of pattern amongst the big solid areas of the "canister". 

On another note, you can buy powder steel, so if you want to try that might be a better bet than grinder dust.

Share this post


Link to post
Share on other sites

Generally speaking folks use mild steel for the can because it's hard to find high carbon steel tube, and Nickel tube is expensive. Welding high carbon plate into a tube defeats the purpose because the weld is not high carbon. Using a release agent like white-out works sometimes inside the can to help it pull free easier.  The powder you use in the can is critically important.  Swarf might work, but if you want a good end result there are a few suppliers out there for Damascus powdered metals.  Kelly Cupples sells a few recipes of steel in powder and is well regarded. As far as the soak, just be patient.  If the forge is set right, and is holding welding heat just relax and drink a beverage or two. If things are right, you can't over cook it.

Share this post


Link to post
Share on other sites

Another nice thing about can welding with a disposable can:  You can run the forge up leaner/hotter and not worry about oxidizing of decarburizing the stuff you are welding.

Back in the mid? 1990's one Quad-State I saw a blade that had been forge welded up from lathe swarf.  The fellow had taken a large coffee can full of lathe swarf and compressed it under a 50 ton hydraulic press and forge welded it.  Great pattern but he could have used a good press to weld with or more cycles/folding as there were still some holes in it.

Share this post


Link to post
Share on other sites

CMS3900

Thank you for the reply. I'll have to look into the powdered steel. I'm still weary about the soak time. I'll have to just try it and figure it out. 

5 hours ago, ThomasPowers said:

Another nice thing about can welding with a disposable can:  You can run the forge up leaner/hotter and not worry about oxidizing of decarburizing the stuff you are welding.

That's a good point, Thomas. 

I would have liked to see that swarf blade. The pattern must have been interesting. A large coffee can full must have made a big blade, even after compressing it. 

Share this post


Link to post
Share on other sites
On 7/3/2017 at 3:34 PM, Will W. said:

... Why not use high carbon steel and fabricate a tube out of that? ...

 

I kid you not, driving home LATE last night on I-10 I was thinking of doing the exact same thing, could use TIG with the joints and no filler rod to keep from introducing mild steel to it if worried about that, but even so, carbon migration should take care of it anyways. 

 

As for the soak time, I imaging a lot will depend on the thickness you make the can. But I would just get it right up to forging temp, nice and bright yellow, and just let it sit there until you imagine it has been long enough, then let it sit about 5 minutes more just to be safe, as long as you're not sparking the steel, should be mostly ok?

Share this post


Link to post
Share on other sites

On a quick search, 5 lbs of 1084 powder is $ 16.25.  I didn't look for other grades because the point was....is it really worth the risk to use salvaged powder when you only save a couple of bucks for all that effort?

 

 

Share this post


Link to post
Share on other sites

I think that all depends on why you are doing it.......if ir is for the joy of doing it, then the cost or effort are not a primary consideration, nor is the potential for failure.

Share this post


Link to post
Share on other sites
48 minutes ago, Jclonts82 said:

 carbon migration should take care of it anyways. 

My thoughts exactly. Plus the arc welds may look cool in the pattern.

 

Kozzy

Wow! That's far more cheap than I imagined it would be. After that little revelation, I'll have to reconsider using swarf. 

Smoggy

It's mostly just for fun. And for the experience. My main idea behind using swarf was 1. I've been collecting the stuff for a long time, thinking it may serve a purpose and 2. It would just be cool to say that the knife is made from the dust of a couple dozen other knives. In the long run though, I may just end up buying powdered steel. I'm with Kozzy, it's a lot of work to end up with an avoidable failure. 

Share this post


Link to post
Share on other sites

Now if you mix swarf with brake lathe powder you can use carbon migration to up the C of the swarf too...

Share this post


Link to post
Share on other sites

Brake lathe powder... Now there's an idea! I have a friend who owns a repair shop, and I'm relatively certain he has a brake lathe. Thanks for the idea Thomas.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this