[sgtnoah]

IMG_0505.jpg (87.11 KiB) Viewed 2136 times

IMG_0504.jpg (88.65 KiB) Viewed 2136 times

Just a (hopefully) quick question... I've been working on the basic joints with both steel and aluminum. Things have been going well with anything thicker than 1/16". Ripples even, width even, shiny weld surface, etc. The issue that I was hoping that you folks could help with is with 1/16" and thinner. I use just enough heat to keep the ripples distinct and not flattening out and wide. As soon as the material wets in front of the torch I quickly pull back just a hair and add rod and repeat. The welds look decent on the front side, and if that was the only side you looked at, things would seem fine. Problem is on the back side there are areas of blistering - not full-on burn through but definitely not good looking. I've been backing off the amperage five amps at a time to limit the pedal (forcing me to not run as hot). The problem then is that my beads start looking tall and ropy right about the time the rear blisters diminish. I'm not sure how to read the puddle to make these come out. This is on steel, ground shiny, #7 gas lens, 12.5 cfh (electrode stays shiny, puddle clean), 1/16" base metal, 1/16" ER70S6 rod.

I got a little long-winded here, and I know that a picture would probably work better.

Thank you so much, and hope everybody is having a good weekend!

-Pete

[weldin mike 27]

Hey,

All you are seeing here is the effect of the plate melting all the way through. Quite often you will see "suck back" in these area, the bumpy bits are pretty much a fact of life on thin stuff. Suck back, where the plate draws back in to the weld, can be managed by adding a little more filler, pushing it in a little, which may cause more of your "blisters" but thats life. Try a slight angle towards the bottom plate, combined with adding a little more filler.
If you find wou back off the amps, maybe drop a size in your filler.

Mick

[awill4wd]

Pete, Mike is right, amperage is everything on thinner materials.
Another trick if you have the room behind where you are welding is clamp some heavy material underneath where you are welding and this acts as a heat sink drawing heat away from the bottom surface.
Regards Andrew from Oz.

[sgtnoah]

Thanks for your suggestions! I just got done watching Jody weld the bike frame with super thin tubing, and am envious of the skill that it takes to do that. My skills are a ton less than his, but I thought that a good goal to start with would be mastering 1/16" and work up (down???) from there. Any more thoughts in getting there would be appreciated...

-- Pete

[weldin mike 27]

Of course practice on the thin stuff, but dont beat yourself up when it doesnt go right, because it is super hard.

Good luck. PS Just about everybody is below Jody's skill level.

Mick

[Wes917]

Travel speed can help reduce as well. The faster you can go the less suck back you'll get. If you can clamp a copper bar back there it will help. Also if you can you could put a back up there and crank the gas up it will help as well.

[ajlskater1]

Speed is key on thin stuff. At the sheet metal shop I work at we mostly do aluminum but if we do do steel its 18 ga or thinner and most if it has no bleed through call outs. The faster you can weld the better. I like to use 035 filler or even smaller for like 24 gauge. I think the smaller rods help with faster travel speed just takes awhile to get used to feeding small diameter rod. Practicebpractice practice.

[Wes917]

Yeah for the super thin stuff I use a small wire also, usually .030 on what we do. I never wear a glove on my wire hand (I know tsk tsk) when using the small wire, it lets me move fast enough to not have the sick back problem

[sgtnoah]

Thank you for all of your suggestions. I've been going low and slow with 1/16", looks like it's time to kick the speed up a couple of notches. I have some .035 MIG wire, so will give that a try soon.
-- Pete