1084/15n20

S.Grosvenor

S.Grosvenor

Fulltime KnifeMaker
Joined
Jan 24, 2010
Messages
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Trying to do some Damascus this winter (a goal) w/ 1084/15n20 tried sat to make up a billet, started with 7 layers seemed to weld good, but after the 3rd fold I had to bubbles developing??? any ideas in why that would happen?
Heats good, brushed and ground dull red, warmed applied borax then brought up to heat and into the press ...

would the thickness of the 15n20 (.058) have anything to do with it??
 
Folding gives a lot more chance for failure, if you don't get all the scale out from between before the welds. It could be something else.. maybe not hot enough? The borax should be liquid and dancing around, plus the billet will be "fuming" when it's hot enough to weld. These tips are from Ed Caffrey's Basic Damascus DVD, which I put into practice the first time this weekend, I made a 36 layer 1080x15n20 billet by hand (hammer), and it so far looks good.
What Ed does is cut and stack his billets after the initial weld, rather than folding it. Take it for what you will, I am no expert but his tips worked for me. I'm sure others will have lots more to say on the subject. I'm curious as well because I'm very new to this as well.
 
Interesting, I was the assistant on this deal but what he was doing was cut all but the last layer, grind then fold... thanks for you experience ... I will be attempting this solo next week so trying to find the cause of the bubbles. Flux was good, and heat was good. I will completely separate and try it that way.
 
that's what I was wondering. Thanks
so the fix would be to make sure the layers are tight enough before fluxing?
 
Personally I allow a forged billet to cool before grinding and stacking to reforge. Having said that I use a power hammer and always hand hammer my first heat to set the weld and expel any trapped flux from between the layers.
I use a crowned hammer and hammer the center of the billet from one end to the other.
Try hand hammering the first heat before going straight to the press, cant hurt.
CW
 
Also hammering from the back/middle towards the front/outside will help squish the flux and gunk out the sides. If you're going to cut and stack, clean them with an angle grinder horizontally (perpendicular to the handle) so the goo squirts out the sides easier (it acts as a bit of a capillary action).. Ed also grinds a bit of a ridge in the middle that slopes toward the outside to aid in this. I'm mostly quoting from the videos he made, but it has worked for me this far.. I have not tried any other method. One other thing.. I used a no name borax at first, then 20 mule team.. the cheap stuff was very clumpy (it had a lot of moisture in it, mostly from being in my shed all summer), and the 20 mule team worked better (it was free flowing and "dry"), but still took a lot and several coats to get things evenly coated. You want the stuff to go down in the cracks and carry away the gunk out the other side, ideally. Use the hammer to help it's journey out from the middle of your billet.. and use light blows for the initial weld before you lay into it.

Also, don't hammer much on the sides of the billet, especially if it's not at welding heat, as it will try and delaminate. I had to re-weld mine because a spot started to open up while i was squaring it up. I will post results hopefully in a weekend or two, once I get it shaped, and heat treated. Good luck with yours, and keep us posted!

Also, anyone please correct me if I'm wrong about something, I'm far from an expert, just sharing my experiences so far.
 
The number one very best thing you can do for yourself is to somehow get an afternoon welding with someone who has been there done that.
Perhaps there's a class through your local organization (try local chapters of ABANA) or just find out what bladesmiths are in the area- they tend to be great folks who are generous with people trying to learn.
Absolutely nothing like side by side time.
I struggled with welding in propane for the longest time until a very accomplished local smith coached me at a weekend class (taught by somebody else- he just happened to stop in) and I swear his mojo rubbed off and now I rarely have trouble unless it's some new twist.
Andy G.
 
The last 4 billets that I made were all pretty much flaw free. Each time that I stacked and did a weld, I had clean metal and then soaked it in kerosene. I did not apply any borax until AFTER I gave it that first squish in the press. I also let it soak in the forge for at least five minutes after that first welding heat/press and went back and did another welding press before I even thought about drawing it out. Every time that I have tried folding, I have had some kind of issue, so I am a cut, stack and spot weld guy. I currently use a cheap little Lincoln wire welder but after seeing my buddy in Belgium tacking billets together with a TIG torch with no filler metal, I am a true believer. I need to get a rig like that eventually.
 
I use boric acid as a preflux (it has a high activity and starts working before borax melts) once the billet is glowing I sprinkle on the 20 Mule Team. I apply all of this over a bucket so anything that falls off is caught for re-use, this means I eventually end up with a boric acid/borax mix, this is not a bad thing. I set the weld with a gentle strike with a slightly crowned hammer one shot dead center in the billet, add more flux, and put it back into the forge, then bring it back up to welding heat, I strike it gently in a widening spiral working from the center towards the edges reheating/refluxing it regularly until I have struck the entire top of the billet, reheat it then start hitting it harder with an almost uncrowned hammer (just radiused edges) Once I am sure it is all solid, I let it soak in the forge at welding temp to allow the boundary grains to knit, I turn it on its side and hammer it with a crowned hammer to check for delamination, square it back up when I do not find issues, and begin drawing out for folding.

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sunshadow said:
I use boric acid as a preflux (it has a high activity and starts working before borax melts) once the billet is glowing I sprinkle on the 20 Mule Team. I apply all of this over a bucket so anything that falls off is caught for re-use, this means I eventually end up with a boric acid/borax mix, this is not a bad thing. I set the weld with a gentle strike with a slightly crowned hammer one shot dead center in the billet, add more flux, and put it back into the forge, then bring it back up to welding heat, I strike it gently in a widening spiral working from the center towards the edges reheating/refluxing it regularly until I have struck the entire top of the billet, reheat it then start hitting it harder with an almost uncrowned hammer (just radiused edges) Once I am sure it is all solid, I let it soak in the forge at welding temp to allow the boundary grains to knit, I turn it on its side and hammer it with a crowned hammer to check for delamination, square it back up when I do not find issues, and begin drawing out for folding.

-Page
Click to expand...

excellent explanation, thanks.
 
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