Not so easy hey...

[Bmouthboyo]

So today I laid my first few beads with my Snap on MIG 130 Turbo on CO2 gas. 0.6mm wire on 1mm steel (bit grubby).

Found it took a while to get the settings to stop blowing through the steel. Even on the lowest (30 amp) it was very hard to lay a continuous bead without blowing through.

I ended up just using the stop start technique which seemed to produce some much more acceptable welds with OK penetration. Do do this I had to up the wire speed to 4/5.

I then tin snipped a bit of the corner out and tack welded it in.

Penetration not so good.

Then stop start welded around.

Again not great penetration

Finally ground back and tell tail signs of lack of penetration.

Can anyone advise how I improve this? Higher wire speed? or leave torch on each tack for longer?

Feel like I learnt a lot from only an hour playing about. Looking forward to practising some more, and reporting back soon.

 

[Wozzaaah]

One way you can improve is to throw that tin away and get some decent steel to practice with.
Something around 2-3mm is good, practice laying straight, consistent beads until you've got decent torch control and a good feeling for the machine settings then progress onto doing joints.
Once you've mastered all that it's time to get some thinner (clean!) steel and have another bash at it.

To answer your question about lack of penetration, try upping the voltage a notch and see what difference it makes though you'll have to be even more careful not to blow through.

 

[Bmouthboyo]

Thanks wozzahh, indeed that is some manky steel lol

I went to a car breakers and a scrap yard and both couldnt help me out I am hopefully picking some steel up next week but I had this laying about in the garage so could resist.

 

[awemawson]

All you need do is clean up bits of that sheet with a flap disk or stripping disk on an angle grinder - it only looks to be surface rust

 

[Bmouthboyo]

yea thats what i did, still spits a little but ok to start with. Surprised at how quickly it burns through.

Is it at all possible to lay continuous beads on 1m sheet?

 

[keith19]

Yes, but it's not easy, and everything has to be just right.

Clean metal (no small pits, which is what you might have on that sheet), 0.6 mm wire, argon/co2 gas, (CO2 on it's own is a bit fierce), and a carefully-held torch, preferably held or steadied with both hands.
Some welder machines are better than others at low settings too, so setting what you have to it's best settings requires some experimenting and practice, time and again.
Something like copper or alloy underneath what you are welding helps to draw the heat away, particularly if you are attempting a butt joint.

 

[Bmouthboyo]

Yes, but it's not easy, and everything has to be just right.

Clean metal (no small pits, which is what you might have on that sheet), 0.6 mm wire, argon/co2 gas, (CO2 on it's own is a bit fierce), and a carefully-held torch, preferably held or steadied with both hands.
Some welder machines are better than others at low settings too, so setting what you have to it's best settings requires some experimenting and practice, time and again.
Something like copper or alloy underneath what you are welding helps to draw the heat away, particularly if you are attempting a butt joint.

Thanks for advice kieth. I am seriously debating the co2 or argoshield. Its just such an outlay for one project on my campervan. The BOC rental route is simply put a rip off. hobbyweld is more tempting, even if not as good value per litre etc it is cheaper overall, but still will be nearer £100 outlay for me, whereas i already have pub co2 from home-brew beer.

Does argo/co2 really make it significantly easier to weld over pure co2?

 

[slimjim]

Thanks for advice kieth. I am seriously debating the co2 or argoshield. Its just such an outlay for one project on my campervan. The BOC rental route ismsimply put a rip off. hobbyweld is more tempting, even if not as good value per litre etc it is cheaper overall, but still will be newr £100 outlay for me, whereas i already have pub co2 feom homebrew beer.

Does argo/co2 really make it significantly easier to weld over pure co2?

The answer is yes!

 

[Bmouthboyo]

Hoping to find out prices from SWG tomorrow. Seems promissing

 

[Lawnmowerboy]

Hi there, i just use pure Co2 and i dont find any difference the welds come out just as shiney as with argoshield

 

[keith19]

Generally, welds on thin metal are easier with Argon/CO2 mix, than with CO2 on its own. Speaking from a few years of bodyshop experience.
On thicker metal, any difference is not so marked, except there is a bit more spatter with CO2, and the weld can look less tidy.

CO2 actually has better penetration because the weld operation is hotter than with Argon/CO2 mix, but this is why it is less easy to use on thin metal.

It's always a problem which to use at home, and depends on what you will mostly be doing; bodyshops mostly use Argon/CO2 mix because they are usually only working with thin metal, and cannot afford to waste time filling holes made by their own welders, so anything which shoves the job through quicker is worth it.

But for something heavier, like farm mig welding, where the work has to be strongly welded but looks are not so important, CO2 is probably better, and certainly cheaper.

 

[Drains]

To improve penetration on a butt joint leave a gap between the pieces to be welded. On thin material 1mm will do. On thicker material, up to 3mm, plus edge prep.

The advantage of leaving a gap is you don't have to bang the volts up to get full pen - you can use a relatively lower setting (it's almost impossible on thicker material to correctly weld without a gap). It also means you have less weld build up on top of the joint, so less dressing afterwards. A combination of the correct gap/prep and the correct voltage, wire feed and travel speed should leave you with the weld in the joint (not on top), a small amount of penetration through the joint and a small amount of reinforcement on top.

 

[Bmouthboyo]

OK So yesterday I picked up my BOC Argoshield Light and Regulator. Wow what a difference, really helps prevent blow through on the 1mm metal I am using.

Top Tacs

Underside

I found laying beads much easier, however when I started practising vertical but welds in preparation for my camper van window surround repairs I had much more problems.


I found at first that the filler metal was almost burning before it touched the metal so had to crank the wire speed up. This seemed to help but blow through became an issue again and most of all distortion.

Having said that although I wasn't laying a continuous weld jumping to another place on only a 5 inch section with no top and bottom tacks is going to get hot and warp.

I think I will try and get some copper heat sinks from flattened pipes to draw heat away and also ensure there is no gap when but welding with such thin metal as I wrongly thought I needed a slight gap.

Will keep you all updated and feedback / advice much appreciated

 

[Seano]

Someone please correct me if I am wrong, but it looks like you are a bit undergassed or you gas is getting blown away, judging by the brown staining, whats you gas set at lpm wise...?

 

[keith19]

"Having said that although I wasn't laying a continuous weld jumping to another place on only a 5 inch section with no top and bottom tacks is going to get hot and warp."

You don't need to do more than a couple of tack welds at a time on small thin stuff like that. Then leave and set up something else for a couple of minutes. Then go back and do another couple tacks. Then leave it again. And so on until there is a continuous seam. Takes patience, but sure stops distortion.

I find this usually works fine on anything a bit delicate.

 

[Bmouthboyo]

Someone please correct me if I am wrong, but it looks like you are a bit undergassed or you gas is getting blown away, judging by the brown staining, whats you gas set at lpm wise...?

I have it set at 10lph at the moment, is that about right?

I agree with the comment about lots of tack welds, I guess patience is the name of the game

 

[Seano]

I have it set at 10lph at the moment, is that about right?

What kind of area are you working in, totally enclosed....open to drafts....? what about your torch angle....?

 

[Bmouthboyo]

I am in the far end of a garage so shouldnt be any wind. Regarding my angle I try and keep is from vertical to 20 degrees either side but sometimes can stray a bit.

It could be the shroud? As It is not a screw on one and did come a bit loose when practising another joint. Might try and secure it a bit better.

 

[Seano]

I have it set at 10lph at the moment, is that about right?

I agree with the comment about lots of tack welds, I guess patience is the name of the game

I am in the far end of a garage so shouldnt be any wind. Regarding my angle I try and keep is from vertical to 20 degrees either side but sometimes can stray a bit.

It could be the shroud? As It is not a screw on one and did come a bit loose when practising another joint. Might try and secure it a bit better.

Make sure you keep it clean inside and free of spatter, make sure your contact tip is tight, how are you gauging you gas flow..? if you don't alreay have one get yourself a peashooter from Steve @ Weldequip.

 

[Bmouthboyo]

Can anyone suggest why i keep getting a lot of brown stain? I am working in a garage and have a 2 guage reg. even at reg saying 20lph i still get it.

If i turn wire speed down its like it s burning before hitting metal, amps up and too hot for metal.

Thanks