Newbie welder…I have a 49 F1 and starting some metal work with a patch panel on the fender. I have a Lincoln Electric (model 180) 75/25 gas. I’m not getting penetration on my welds. My sheet metal is 16ga.The weld seems to penetrate the new sheet metal but not the existing older truck metal. Any preferred tips or settings for my welding?

 

Cleaning existing surface areas , and removing all rust is important. Also this may seem silly, but make sure you have a good ground.

 

It wouldn't hurt to find some scrap to practice on a few days ( weeks) before you go at the truck ! Dean

 

do I clean to clean the rust off on both the front and back to get a good weld?

 

Did you just get this welder or have you had it already? Do you have the polarity correct? I just helped a friend on his Lincoln welder....he bought it and it was set up for flux core. But he was using argon. Welds were horrible. Quick change of the polarity by swapping the lead connections inside the box and it welded beautifully. His has graphics on the cover showing the set up for flux or argon. Your probably will too.
Also lots of youtube videos out there to help you get started. good luck

 

2x on the cleaning first. I’ve always used a 60 grit flap wheel to clean the edges of the old and new before welding. If you can get to both sides, that’s ideal.

I’ve also noticed that sometimes the new sheet metal is not quite the same thickness as the old so that may contribute to what you’re seeing.

If you’re using .030 wire, I strongly suggest switching to .025 (you’ll need new tip as well).

Skip around a lot with your stitches to minimize localized heating and the warping that can come with it. I’ve used an air nozzle at times to immediately cool after each stitch weld spot on parts I don’t want to warp and while its a pain to do, that seems to help.

A technique that I saw somewhere that helps me is to double tap the weld. First trigger pull is a really quick zap followed by the second which is a longer pull and does the stitch weld point.

Play with the gaps on the test coupons to see what works best for you. I’ve found that a .030-.050 gap works best for me but sometimes a wider and narrower happens due to how accurate your cut is but that’s not the end of the world.

As mentioned earlier, Practice before starting on the real thing. I’m not a professional welder but I always do some some tests before welding to make sure of my settings and get into the groove.

Hope this helps! We look forward to seeing your progress!

 

Lots of good advice. I strongly recommend you do as others have mentioned and find some scrap to practice on. When I weld patch panels, I find that if I mental count the time I'm actually welding each bead, it works best getting uniform results. For instance, as I squeeze the trigger, I might count like one thousand one, and let go of the trigger. Experiment and you'll find what combination of heat, feed, and time that works best of you.

Patrick

 

This should also be noted . The videos make it look easy, soooooo much more to it than meets the eye. Patch panels take time and very careful fitup and clamping. You cannot spend enough time on your fitup!!!!! It will save you alot of frustration trying to fill a huge gap. Remember the 7 Ps Prior Proper Planning Prevents **** Poor Performance.

 

yes! At least 3/4 from the weld line. A 2" fiber stripping wheel (blue or green) does a quick and easy job without removing good metal. MIG is somewhat more forgiving of dirty metal than TIG but a totally clean surface will give a much more successful weld. SET the welder a little hot and weld with a overlapping series of 1-2 sec. spot/tack weld beads on sheet metal keep each successive bead at least 6" apart and cool the metal after every 3 beads with compressed air gun the metal should be cool enough to comfortably lay your bare hand on the last weld. I use .023" ESAB SPOOLARC Easy Grind wire for all my sheet metal work up to 14 ga. Somewhat difficult to find as most welding shops, even ESAB dealers have never even heard of it. (proprietary alloy has no alloy number. Accept no substitutes, Says Easy Grind boldly on the label, only available in 10# spools.) But once you use it you won't use anything else. Practice on scrap or cut coupons off the new metal. Also keep your stick out short 1/4 - 3/8" from contact tip, NO MORE. Always start each bead with a freshly clipped wire end. adjacent beads should start from center of previous bead not next to it to prevent pinholes. Note series of 4 beads 3rd from left top of the patch for proper overlap.

3rd round of spots. Good penetration, note bead profiles.


Completed weld will look like this. not pretty, but with penetration that will allow sanding without warpage or cracking.
After grinding smooth ready for a light skim coat of filler. I try to not need more than 1/16" of filler.



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