still filling in holes and such in the engine bay, and still having problems. there is a TON of spatter, doesn't appear to be enough penetration, and when i tack, it doesn't really fill the gap, it kind of just sits on top and is hollow on the inside. its like it bubbles instead of just setting in. this causes me to have to fill in a billion little pin holes all over it after grinding it down. what is causing this and what can i do to correct it?

i am using a Lincoln 140, .023 mild steel wire, heat C, wire speed 5, gas 17psi

 

can nobody help me with this? perhaps going with a thicker wire? .030? .035?

 

Maybe slow the wire down a bit.

Also, we used a brass hammer on the back sides of holes. It helps a ton since the weld wont stick to the hammer. Makes it much easier to fill in holes.

 

gas should be measured in CFM

what type of gas are you using?

try matching your wire speed to your amperage.

so if ur going to be welding at half wire speed (pretty decent place to start maybe a little less) match that with half amps. it should keep you pretty close to where u need to be on most 110v machines.

 

yes what gas and CFM are you using? also make sure everything is as clean bare metal as possible both sides (if possible).

 

the gas is 75% 25% mix. both surfaces were as clean as they could possibly be. some areas i cannot get anything behind, so the copper is out of the question. for instance, i picked up a junk hatch off of some VW in the junk yard to practice some stuff on. i cut a circle out of some .050 steel and tacked it into place to shave the rear emblem. i put my tacks all the way around, and when i ground it all down, there were little pin holes everywhere, and i could actually see the outside edge of the blank just as i had originally cut it, so it looks like the weld isn't penetrating both surfaces

 

so how much CFM are you flowing your gas at?

try tuning up the gas a little.

the tank PSI should be 800psi+

 

turn the wire speed down and up your amperage.

 

The pinholes are known as porosity...usually caused by a problem with your gas....either not enough,or way too much actually blowing the weld puddle away from where you want it...Porosity can also be caused by unclean metal....you say you cant place anything on the back of the holes....did you clean the backside?????could be drawing paint,rust,etc into your weld....hope I could help a little.....justin

 

seems like he got it to work... or hes just working with his no-gas non shielded welds. hah

 

make sure there is no paint on the surface first off. thats the hardest part with filling in the engine bay... especially the deep holes that are threaded for accessories.

 

with the pin holes and such, some of these gaps were rather large. i was easily able to take a screwdriver into these gaps and the blank came right out. i don't understand what i am doing wrong. again, the blank is as i made it after i sanded away the welding material from it, and so is the spot on the hatch. its almost as if its just sticking to the metal, and not actually melting into it. i have it on "D" (the highest setting) and wire speed of about 5, gas is now up to 20cfm

 

is it possible that the ground is allowing for the arc to start but not good enough to get good penetration? should i maybe find a better ground?

 

It could, is the ground on clean, bare metal? Keep it close to where you're working too.

 

most grounding clamps are crap. good ones are definately an advantage.

but all clamps work. just make sure its on clean bare metal on the same part your working on.... i.e., not on the engine if your welding the chassis. and make sure you clean the part your welding WELL and get it crud/paint/etc free before welding.

 

okay, because i have it bolted onto something and the ground is not on the hatch itself. so i'll go ahead and clean up one of the corners of the hatch and use that as a ground instead. not sure why i didn't think of this before

 

so, i got back out in the shop last night and was still having the same problem even after i located a better/cleaner ground. scratching my head, throwing things, and getting really frustrated, i decided to start cleaning up. i ended up opening up the door to look at the diagram on the welder. i was using all the right settings given what material i was using. then i look to the left at another diagram for the routing and wire rotation direction. it just so happens that the positive and negative cables were reversed. according to the diagram, the cables are swapped when using sheilded wire (no gas) than using mig wire (with gas) so now i am getting really good penetration and the weld isn't pooling up like crazy like it was before

 

another update, even though i was finally getting good penetration, the welds were still coming out like craters and causing small pin holes. my neighbor, a certified welder, came over the other day and was checking things out and noticed that the gas lens was really narrow and too far back on the gun, causing the weld to have little-no coverage, so he gave me a larger lens and it made a world of difference. welds are coming out great and now i am really getting things done finally. will post pics as i get things done