Problems with welding - new to welding

[Rhysd1309]

Hello. Thanks for the replies on m other posts, wish I had something useful to add to somebody else's!

Anyway, I have only been welding a week, I watched a few videos on YouTube then dived straight in. I have a wolf weld 135 MIG. I run it on 'no gas' with the flux cored wire. It is also positive ground.

Anyway, I was quite impressed with my self when I welded some 40mm box section and 40mm angle together to make a bracket to hold a tyre machine down in my van. Found it quite easy to make a decent looking weld.

Now the problem arises when I try and weld said bracket to the floor of my van. The box section is 3mm thick, and the floor of my van I guess 1mm. The box section is rounded so there is a small gap between surfaces.

What happens is, when doing a uuuuuuuu pattern, the weld sticks to the box section, and sticks to the floor of the van, but not in between (until I go over it again)

Sometimes the wire will extend into the gap and stop the molten flow

The area is prepped, I am earthing the box section. The welder is on heat setting 4 (out of 6) and the speed is just past 12 o clock.

If I try and go slower I just burn through the floor, tried all different settings and all to no avail.

Sorry for the essay! I'm pretty sure the answer is to give up and pay somebody to do it, but I love trying things myself and it would be a valuable skill to hold.

 

[mike 109444]

As you are new to welding then you could try spot welding some 2mm to the bracket then spot weld the bracket to the vans 1mma
Some nice 10mm holes in the 2mm will allow a good size spot as per red arrows.
If you start on the 2mm then drop into the hole, circle around the hole and stop!

 

[Rhysd1309]

Thanks for the advice, might try that on the two brackets I've got left. Anyway, here are a few pictures that I have just taken (it's freezing)

The above seems ok to me, by no means as good as most on here, but good enough for what I need it for (and it is my fee nod ever attempt!)

This last one shows what I mean abit. It's as if the arc stops sometimes, and the wire pushes back at me. One minute it's going ok, the next I make the crappiest bead ever!


...

 

[Robotstar5]

What sort of load are you going to put on those welds with the tyre machine, might be safer bolting through the floor into spreader plates?

 

[Rhysd1309]

Hi, already tried that with last van, unfortunately there is just too much crap to remove from under the van, also the structural beams are often in the way of where the bolt would have to go it's just not worth the hassle (I say whilst having loads of hassle welding it!!) of removing tank/. Exhaust ect...

 

[cumbriasteve]

It may be worth considering changing to gas instead of no gas, you would find it totally different, much easier to control.

 

[Glyn]

I'm surprised no one has pointed out the amount of paint. The usual first piece of advice is to make sure you are welding to clean metal. I'd guess the arc stops because of the paint.

 

[Mr shiney]

Brave jumping into welding something that looking at the welds is likely to break loose and brain you or someone else.

Can I suggest getting a load of scrap and practicing on that until you can produce a passable weld?

 

[norlander]

from what I recall from when I did some Mig, the earth needs to be good on bright shiney metal-the wire poking back at you and stuttering maybe because of a bad earth?.
When I have gaps like that I run a bead along the box section and a bead along the plate then join the two together with another bead.
You must make sure you clean off the welds(wire brushing) before joining the two.
As someone has said, I think you need to fix the top of the machine to your van with brackets, the welds may let go if they are stressed towards the interior of the van.
Most welding is preparation, positioning and practice so make sure the joints are well prepped.
I'm going to state the obvious-make sure you know the location of the vans fuel tank when welding on the vehicle floor or lower sides and be aware of any underseal catching.
HTH

 

[Jim Davey]

You can encounter problems with paint if you only clean one side, I've had this loads of times where the metal heats up and melts the paint on the back-side causing porosity, it's not an issue on thicker sections but thin painted metal can really be a problem.

 

[aametalmaster]

Remember too that there is a gas tank under there somewhere and you don't want sparks and flame dripping down on it. Just a thought...Bob

 

[sapperb]

Maybe try welding the bolts (upright) to the floor of the van, and bolt the tire machine to those??