What are your tips/tricks for welding thick to thin steel?

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Hey folks!  I would like input please.  My neighbor has made an enclosure, which he wants lifted one inch at each corner.  The enclosure is made up of 3/4”-inch rectangular tube steel that is .120” thick.  But the solid blocks of steel he wants welded under each corner are 1” height (1”-H x ½” thick x 4” L) --- see photos of the bottom of the enclosure with an example of where a block of steel needs to be welded.  In my past, I’ve successfully welded different thicknesses of metal together, but not this big of a difference.  I already know that I have to set my heat setting for the thicker piece and focus the weld puddle on the thick while splashing over the puddle to the thinner piece. But are there any other tips/tricks you would suggest?  I read somewhere to use a magnet to attract the weld puddle, but how?  BTW, I’ll be able to do all of the welds from a flat, horizontal position, so the position is not an issue.  I’ll be using either an Everlast Power I-MIG 200 or Hobart Trek 180 with .030” Lincoln Super Arc L-56 mig wire and C25 gas.  Please post your tips/tricks at your earliest convenience. Attached ImagesAgape GuyEverlast Power I-MIG 200 (dual voltage)Everlast PowerArc 200 stickHarbor Freight Titanium 125 Easy FluxHypertherm Powermax 30Way too many power tools
Reply:Bevel, bevel, and more bevel.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Keep in mind, a weld is no stronger than the thinnest member. You don't need massive welds to connect the two. Just enough to get enough heat into the heavy stock to get good fusion. I'd agree with Terry that beveling would help..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
Reply:Yeah, that's a pretty big difference!  I'm just a hobby guy, but I would bevel the edges at like 25-30 degrees and about .120" deep.   Then I would just run my bead so the edge just washes into the frame.  Since you're welding to the corner of the tubing you have a little more effective thickness than say an edge of .120".  It should work out just fine.
Reply:The tubing is almost 1/8" thick so shouldn't be a big problem with MIG. Preheat the thick piece with a torch to insure proper fusion.
Reply:Yes, first preheat the thick piece almost cherry red, then set your mig for the thinner stuff and dwell mostly on the thick material.....Watch the puddle and make certain you see the thick stuff wetting in along it's edges....rule of thumb is to set heat to favor thin, then concentrate heat on thick and lick it over to wet in the thin without blowing a hole in it.....The more you preheat, the less you bevel......Set up a few practice runs
Reply:I’m just a hobbyist too. No matter what rod I use, 6010, or 7018. Even Mig, I run a J motion. Keep the long part of the J on the thicker material. Just let the curl of the J kiss the thinner material.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Just clean off all the weld areas, clamp it, set the mig at 120 or so and weld it up. Its a spacer block, not holding up a bridge or building.www.georgesplasmacuttershop.comPlasma Cutter and Welder Sales and Repairs--Ebay storeTec.Mo. Dealer Consumables for the PT and IPT torch's
Reply:Originally Posted by mechanic416Just clean off all the weld areas, clamp it, set the mig at 120 or so and weld it up. Its a spacer block, not holding up a bridge or building.
Reply:Thx all!  I did about 125 amps (flux-core amps) and directed the gun at the thicker piece after beveling the heck out of it.  The splash puddle to the thinner piece was a little hot (a tiny bit of excessive burn through), but overall it worked out well with strong welds!Sent from my SM-N910P using TapatalkAgape GuyEverlast Power I-MIG 200 (dual voltage)Everlast PowerArc 200 stickHarbor Freight Titanium 125 Easy FluxHypertherm Powermax 30Way too many power tools