Need Advise on an non typical weld

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I make pattern welded steel (also called damascus). I use a starting billet of 5 to 8 pounds that consists of thin flat stock of two different steels. The thin stock is tacked together and a rebar handle is welded to the billet. I am looking for help on how to make the best weld between the bar and the billet. Here is an example picMy problem is that the handle/ billet often fails during forging at extreme temps. I only had a 120v mig but  just picked up a Miller AC/DC thunderbolt. How would you pro's recommend making this weld. I am looking for prep, electrodes, Ac/dc, amps, basically the best way to ensure that this weld does not fail because when it does, 2400 degree flying steel is scary and dangerous.ThanksJohn
Reply:Use 7018 on reverse polarity. Don't use rebar for the handleAirco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:It may be worth the others to know, it's high carbon steel such as 1080-1095Have you tried using a steel handle other than rebar ?
Reply:I can use  mild flat bar, angle, or round. Whatever is recommended is what I plan to use.
Reply:If I recall correctly, you start by smashing that big stack of metal down right?If so, the spots where you welded the "handle" have it's welds "moved" while hammering the stack down.When the welds move, they break, and the handle comes off.I think I'd make a set of tongs to hold the stack.If I'm way off, let me know - I don't forge iron Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:make it with an odd number of plates and make the center one long enough to use as a handleMillerMatic 252, HTP 221 w/cooler, Hypertherm PM45, Lincoln IdealArc 250 AC/DC"I'd like to believe as many true things and as few false things as possible"
Reply:I would choose mild steel over rebar. The reason is rebar is usually of unknown origin. It might be soft, or it might contain really high carbon steel. Rebar is notorious for welds breaking due to this. You can even take the same 20 ft bar and cut it up and have some welds work fine and others break.I'd also choose a decent sized bar as the handle. I know I was bending the 5/8" and 3/4" mild steel handles I welded on to the 4140 I was using to make my my top cut and the flatter and set tools that I forged under the power hammer. The repeated bending ( since I was new at this and wasn't always getting the stock positioned correctly under the hammer each time) caused a number of cracks to eventually appear, but the weld stayed solid enough to get me thru. Considering the weight of the 3" square I was using for my flatter, I'd probably try to go no less than 3/4" and bigger  if possible. The added weight of the handle did help balance and offset the mass I was forging.I also found that when I had to make use of the gas forge vs th ecoal forge that I had more issues with the handles bending. That's because it was harder to concentrate the heat on just the mass I was forging and not the handle. In some cases I could get the handles pretty soft and a good quick snap of the wrist to "toss" the weight up under the hammer would cause the handle to bend even without hitting anything. I found in a few cases I had to cool the handle back about 2" from the mass. That kept the water away from the tool steel, yet reduced the heat that was building up in the handle. Not doing this with rebar has a very good chance of causing cracks as many times rebar gets ver brittle when quenched. You will want a full penetration weld. Usually the easiest way to do this is to bevel the handle and weld it out. You can bevel all the way around the piece, or cut a slant at the end and weld that all the way up. I'd also lay a decent fillet around the weld to get as much surface area on the stack as possible.As far as what to use, In your case, I'd go with the stick machine on DC electrode positive and run either 7014 or 7018. I'd use whatever rod you run best. Make sure you get all the slag cleaned off so you don't bury any inclusions that will cause weak points. For 3/32" 7014/7018 I'd probably set the machine at about 95-100 amps, but depending how you personally weld, will change what amps work "best". Usually if the slag is peeling off on it's own or with little to no effort, your settings, rod angle etc are pretty much perfect. If you are beating the snot out of things to get the slag off, something isn't right. Even 6010/11 would work if you can run it well. It's a deep penetrating rod and it burns thru a lot of crud like small slag pocket, but it's not as ductile a weld as 7014 is and 7108 is even more ductile than 7014. In your case I wouldn't go with 1/8" rods on some thing this small in diameter. If you can't easily get rid of all the slag, don't panic. Take a wire wheel to the welds as your 1st option and if that doesn't work, use a grinding wheel. It's more important not to have slag inclusions than it is to lay down lots of weld bead. If you end up grinding off some "good" material to get rid of the bad, no big deal. Be sure and post up plenty of picts of this and your other forge projects. There are a lot of guys here interested in blacksmithing. I do some forge work, but haven't gotten into damascus yet. I'm not really into blades like some are, but love the look of patterned steel. I'll probably end up trying it at some point, and would love to see how you go about things..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan