So, I'm shaving my engine bay and I have a flux core welder. Just welding up a bunch of holes and I've been teaching myself how to use it along w/ help from the internet of course. And whenever I weld, things go GREAT or so it seems. But, when I grind my weld down, they end up turn out like this....





anybody have any good tips/tricks/advice to weld up holes better?
I notice that sometimes I get really lucky and my weld turns out perfect and when I grind it, it's super flush. but then, this crap happens a lot making me weld it closed again then grind AGAIN. that sucks. why is this happening?

any help is appreciated, thanks in advance.

 

I had the same issue. crappy quality wire along with too much or not enough gas was my issue. since your using flux core wire Im not sure what the issue is for you. have you tried more heat to get a deeper penetration?

 

are you using an ebay welder?

 

Contamination, unsteady puddle, inconsistencies, etc. What are the settings on the machine?

 

What exactly are you welding? If it's thin rusty crap and you are trying to zap holes shut that could be your problem. Anything that is flux cored or flux coated will have a tendancy to have porosity issues if it's run to cold. No chance for the slag to boil to the top of the puddle if it freezes to fast. If I've guessed correctly on what you are welding try cleaning as much of the crap off the parent metal as possible, zap everything shut, grind it down and then run over it again set hotter or going slower to try and boil the impurites and slag inclusions out.

Note. Most FCAW wire is not recommended for multiple pass welds so there is a chance even what I suggested wont work. If that doesnt work bust out some 6011. That rod will burn through anything.

 

Well, whenever I try going for more heat, it seems to open the hole up bigger.
Btw, it's electric powered, no gas involved.

Harbor freight.

I tend to put min. power on the machine, it's either that or max.
And I play with the wire feed settings. Like I said in my post, sometimes I get lucky no matter the settings.....idk?

I'm welding holes in my engine bay, and I do try cleaning in and around the hole, although welds still end up doing this, as I told the other guy, it doesn't happen ALL THE TIME, it'd just be nice if it never happened is all.

And on some holes, when I would begin welding, they just get bigger until I create good puddles and get those together.


Thanks to all the help so far. But, I'm still lost in what to do. I clean the area.... remember, it's thin sheet in the bay, so what setting would you recommend? how much stickout is good? and why do i have so much splatter no matter what wire speed?

 

here's your problem..


seriously though, you need to get some scrap metal (from an old body panel/door skin) and practice.

i used a fluxcore welder to swap out one of my motor mount brackets, and i had no problems getting the machine set up... but it was a lincoln that a friend of mine owned.. and it didnt hurt that i new how to weld already.

this is what a fluxcore spot weld should look like.

 

any hints?
did you start from the outside of the hole and move inwards? or did you just start on the inner edges of the hole right off the bat?

 

how big is the hole? maybe just cut a piece of scrap metal that will fit in the hole and tack around that

looks like its just not hot enough

 

I know it sucks but HF welders arent the greatest. Follow the tips above and see how that works out. Im new to welding as well so I know what you have been going through. I read A LOT of information on the internet before i even picked up my mig gun. Theres some good stuff here: weldingweb.com

 

Clean out all the paint and rust beforehand and hold or clamp a piece of aluminum or copper behind the hole to back it while you fill it in. That way you can get it hot enough and do it in one short weld.

Those motor mount plug welds are really a totally different kind of weld that can be done with at least double the heat you need.

 

hey wat settings are u using on ur harbor frieght welder?

also is it the 90 amp mig welder?

 

Wow, such an old thread. LOL

but, I'm usually on the low setting. I'm done welding my bay and ****, it took me a while but I taught myself the hard way.

IT IS the 90 amp mig. basically, I was rushing my welds and the metal around kept on melting........ yadadi? so, I learned that if I took my time and went slow, the end result was much better.

 

Yeah i know its and old thread lol

what is the wire speed u had it on?

how are u welding the big holes? Because mine get bigger instead of closing up
how are u moving your torch to close them holes up.
any links u can send me to where u learned to weld?

Can i see pics of ur finished engine bay done with this welder

 

I experimented with different wire speeds.
I tried going with 4 and it was good.


I see that's you're interrogating me because you want to buy one and need to know how to use it. LOL.

 

That sucks the machine doesn't have a numerical dial for the amperage. I'd think around 23 to 25 something amps would be nice with the wire speed at 4 but never have done an engine bay myself.

 

i am sking the questions because i have one but instead of welding up the holes i am making the holes a bit bigger

so any advice i would really appreciate it

 

^bump, I am currently going through the same issue. It's like it's too hot. As I move thwelder across the hole it just keeps opening the hole up. This only happens on the thinnest metal. I have a Lincoln 140 HD and it is set on the lowest setting. Should I use as shielding gas? Thinner flux core? Any advise?

 

i also started with a flux core to teach my self and i still use it all the time just cuz its so much more convenient than using my tig. the problem you guys are most likely having with the holes opening up is that when you weld sheet metal like that your not supposed to run a bead around the hole to fill it in you need to make several tacks to close the hole and any hole 1/4" or bigger should have a piece of metal cut to fill the hole and tack all the way around the filler piece. just pull the trigger for one second let off and move to another spot and if it still burns through then your set too hot

 

another problem is youre not using gas. flux core no gas wire is a shitty weld to begin with. get a welder were gas can be used and by a spool of .035 standard wire and youll see a big difference.

 

I've had a few issues with that too..turn everything down and now its just going back over every pin hole until it grinds smooth. Kind of a bitch but it will be worth the extra time and effort in the end. I've only been able to lay a small bead in a few areas so far. It's all spot welding.

 

Running into the same thing myself. I picked up the following just to work on shaving the bay and perhaps make small brackets for future projects etc.

https://www.harborfreight.com/easy-f...der-56355.html

I realize this is not the best by any means but I wanted to craw before I walk. The reviews were pretty great on it but my only experience is watching some youtube videos where they generally have perfect welds and fail to mention any type of settings utilized.

I got a few holes filled up but during grinding mine look like yours. I also blew a few holes wide open when I got up on the top of the engine bay near the fenders as it seems stupid thin in that area.

I am going to pick up some random bits tomorrow to practice more without creating more work in my engine bay.

What are you using to grind it down afterwards? I was using a 80G flap disc on a grinder but it was taking a bit of time to smoothen it out.

 

Return that and pick up this.

Best bang for the buck right now. Pick up a bottle of 75/25 argon/co2. Gas shielded is better for thin sheet metal.

Using fluxcore on sheet metal you really have to dial down the settings in order to not blow through the material. Plus, with the flux and the slag coating, it's more of a mess to clean off, technically you're supposed to remove the slag before attempting another weld/tack, and with thin gauge sheet you're going to be tack stacking.

 

As far as grinding...

For 4" grinder I use 3m fiberdiscs 60 grit for rough grinding and blending. Let the grinder do the work, don't force it, grind lightly and let it blend out.

If you want to finish blend, we use a dual action sander with 80g stick on discs. You can blend out a really nice finish with that.

 

Damn, i knew someone was going to say get a different welder. Not sure mine is returnable ill check it out tomorrow. I really just wanted to fill some holes, add a few plates inside the bay and make some small brackets for the fenders/bumper etc. I did tinker a little more this afternoon on lunch and filled a few holes that looked way nicer than the day before however I also still blew through on the fender area pretty bad. Going to cut my losses there and likely use a small plate/fill LOL

Appreciate the info Ill see if i can return this thing and order the one you mentioned.