Anyone want a laugh?

[Mowflow]

Anyone want a laugh? First weld opinions please

I'm afraid this is another one of these "look at my welds" threads.

Using a Snap on 2135 which I believe is the same as a Cebora 130, 0.6mm wire and a big can of hobby weld 15.

I know it's zintec (doing it outside to avoid dying) and it's only 1mm so I shouldn't be using it but it's better than the galvanised sheet I used before it (newbie error no1). I tried some 3mm a few weeks ago using one of the disposable canisters and the welds were better. Learning to do car repairs so being good at 3mm is useless.

Welds were messing about with no real though, just trying to string together some short runs and spots. I experimented a fair bit with the angle and distance of the torch trying to get that satisfying sizzle (achieved it every now and then). I just gave the sheet a quick scuff with a twist knot wire wheel so possibly not cleaned well.

The torch was spitting all over the place so after some initial reading I thought the gas was maybe not getting through as I could hear a bit of a hiss from it. Took it apart last night and despite a slight hiss I don't think it's for the bin as the trigger is definitely sending gas the right way.

The welder was set to min/1 or both switches pointing down. Wire speed set at the 12 o clock position (which is about 6 on this machine). Tried some slower speeds as well.

Now for the embarrassing bit. Suggestions, advice, ridicule welcome.

 

[Barking Mat]

You're sticking the weld to the metal which is a good start, when you squeeze the trigger and you get the initial puddle, don't move too quick, stir it and from there keep working it, do you manage to continually maintain an arc or is that the problem?, play with your wire feed speed, I think when I mig I have about a cm between the work and the mig torch, and just keep practicing, failing that checkout the tutorials at the top and you tube. Good Luck

 

[Mowflow]

Have read the tutorials and watched loads of videos on Youtube so theoretically I'm an expert (almost). Practically it's a different matter. Practice, practice and a bit more practice I think.

Being more patient with movement might be what i need to do mat. I'm so paranoid of blowing holes that I'm maybe going to quick. I'll be welding a wafer thin french car so the thin metal technique will probably have to be employed.

I'm very off and on with maintaining an arc. You can maybe see that in the 2 longer runs to the right of centre I went not bad for a bit. I'll play with wire speed. The other controls on the MIG are very basic and flicking either switch results in massive holes. may need to play with the regulator a bit as well as i haven't worked that out yet.

 

[Barking Mat]

You need to be able to lay a decent bead even if its on 3mm as in my experience 1mm with a mig is quite difficult for a beginner. Go back to something thicker you're not frightened of burning a hole in, lay down some good beads, play with the power knob to get different levels of penetration and the wire speed, don't just jump in the deep end with thin thin steel, and if you do, a good heat sink, I digress. If you do car stuff it needs to be right, practice, practice, practice. Star on something thicker it's easier. I do.

 

[Mowflow]

I get what you are saying about using thicker steel Mat. I did practice for a few days on some thicker steel and things went pretty well from the off. Jumped onto the thin stuff and completely different story so seems a bit like swimming a few lengths in a paddling pool in preparation for swimming the channel.

Had a bit of a play last night following your advice of moving the pool about a bit and things went a bit better I feel. I was definitely moving the torch too quickly and pretty much not building up any pool at all.

A bit thick and thin but improved?


Top one here was probably one of my best. Got patchy towards the end due to excitement.


Penetration


Tried some but welds by cutting a few slots on the edge. They were terrible


I did get one decent one in the centre here (apart from the very edge)


More practice this weekend.

 

[Flapdisk]

You're getting there mate, but you will find that when you are welding thin stuff for real on a car or van that you will have to "Stitch weld" that is rather than doing one long continuous weld which will most likely blow a hole in the thin metal, but if it doesn't the sustained heat will warp the panels, so the technique is to weld in spaced out short stitches and then go back and fill in a bit more and then a bit more and so on

 

[Mowflow]

Yeah, i've been told to move around the panel and do like short runs of maybe 1-2cm between spots/tacks that are already around 1-2cm apart. Is that the right way to go about it?

I'm sure i read in the tutorial on here that it's best to start and finish runs between spots/tacks

 

[John_Duffy]

Great photographs though!

 

[secretsmoker]

Having done a lot of thin stuff recently, I would say whilst learning on scraps it's perfectly ok to burn a few holes here and there. Only then you can have a go at filling them in!

In fact, once you get a feel for burning holes, then you can start to get a feel for playing around with the weld pool whilst on the very brink of blowing through. Concentrate on getting really good at timing the melting of spots about the size of a 5p piece. This is about all you need for car panels, hundreds of neat little spots! Might need a tiny stir to get the edges to melt but not very much movement necessary. Lift the trigger just before it starts to get too hot. After a while you will recognise the signs. Building up a reflex action for lifting off just before you blow through will serve you well for joining panels together neatly.

It is possible to do short runs on the thin stuff but I only found a couple of places where I needed to do it that way. On cars the amount of heat and smoke you will generate burning paint/underseal from longer runs will soon become discouragement enough!

A couple of slightly black artsy techniques do exist for bad thin material butt joints which may be rusted on the other side/contaminated etc. Neither of the techniques are really advisable, and should not be necessary with good prep, but in areas where you can't really prep very well... As penetration isn't really the issue, it is sometimes helpful to 'wiggle' the torch across the gap to whilst starting the arc, lifting off just as everything melts together into a tack. This sort of thing has saved me a few times where my panel gap ended up being a little too wide or when trying to weld an area which I knew was just going to fizzle into vapour. Main thing is probably to maintain decent gas coverage and distance though otherwise horrible 'pigeon poo' which just chips off is the result when it goes wrong.

When you do blow through I found that it is possible to build back up but that involves gingerly melting around the hole, trying to spread the heat back away from the edges. Once you have something solid laid around the edge then you can melt across the hole and the welds around the edge take a bit of the heat away. Bigger holes happen occasionally, on non critical areas it is possible to get creative and 'horseshoe' your way up until everything is close enough to melt together in the middle.

 

[Petefeet]

and for filling in holes the 'block of copper underneath' technique works a treat too1
p

 

[Mowflow]

More good advice. Much appreciated.

Been practicing a bit more over the last week. Doing (squinty) runs is all well and good but I found i burnt through a lot easier on but welds. I just cut a load of slits in the edge of the sheet and tried welding them back up. I got some copper pipe, hammered it flat and folded it all up to make a sort of block. It definitely helps.

Fortunately the areas i need to weld on the car are all small holes, cleaned back to bare steel on both sides, non structural and if worst came to the worst could actually be hidden. I intend to do the best job possible though.

A few recent but welds. Tools pointing at the better efforts.

 

[anjum]

Looks like you need to wind the wire speed down, watch the tutorial on wire speed again and again and move the torch slower. You will blow holes on 1mm but you will get the hang of it.

 

[Bede]

On sheet that thin with mig you need to repeatedly spot to build up a run.

I read earlier in this thread to place tacks 1-2 cm apart and build up with spots between them. In theory this is half correct as staggering between tacks will dissipate heat and keep distortion down but since your welder is so low you're not really getting penetration.

The best thing to do is place a series of tacks at larger intervals to keep the piece together but then start at one end and spot until it fills the gap and you get a couple of crackles, then stop, let the weld go from orange and liquid to red and solid then spot again for a couple of crackles. Keep the heat local to aid penetration but stop just short of blowing through.