Welding

I've had a Mig welder for about 8 years and used gassless wire for the first 6years, then I used my mates welder with gas and started welding likely a pro. So I went down to the local gas supplies and got meself a bottle of Argon and was soon welding like a pro at home (well more often than not anyway). But every 3 months a get a bill for $42 gas bottle rental. It hurts a lot when I haven't even turned the welder on in that 3 months. Today I returned my half full gas bottle (that's all I've used in 2 years) coz I can't take it to Canberra. So what do others do in regards to welding, especially the delicate bits of the body work? Mig or Arc? Gas or not? Anybody found a cheaper alternative? I have heard you can get disposable gas bottles. Don't get much out of them, but then it's only odd job where its really critical to get a nice neat weld.

Any tips?

try to keep using gas it is the easy and less hassel way of doing the job.. my bro-inlaw was telling me he to was jack of renting bottles and he said that he was told about disposible bottles of argoshield,,supposidly from repco shops ..if you are not useing much gas- have you been using the smallest bottle available--also linde gas is cheaper than bo-gas

Howdy Scoutman,

I find I dont use the mig at all these days on body work. The mig leaves a hard weld which you cant hammer weld well at all so if it starts to distort there isnt much you can do about it. The heat generated grinding a mig weld on body work can distort the panel itself which is a problem.
I put up with the cost of bottle hire and do 90% of my welding with the tig or oxy and hammer / dolly method. Nothing to grind and you dont need bog after.
The oxy....well its my favourite tool so Im happy to pay the bottle rental there to.
The way I look at it is - work an extra 5 hours a year to cover the rental of bottles....small drip in a year for the luxury of having gas at hand when you need it for both cutting and welding.
I get plenty of cartons of cans to from mates wanting to come use me gear so Ive got me rental covered a different way also.
Carton of carlton mids if you want to use me gear, carton of bundy if you want me to do the welding.


Basil

Thanks Basil,
Pity I'm not moving over your way. A carton of Bundy to get you to do my welding sounds like a good deal.

G' day Barry and Dennis , I am in a bit of quandary of what to do about welding equipment myself , I also have a small gas/ gasless Mig welder at home , which I might add I have hardly used so far .
It seems every one I speak to has a different story of what to do.
Dennis ,I have heard you shouldn't use gasless wire on thin sheet metal as it takes more amps, therefore makes more heat , therefore more distortion.
So I was interested to read of your big improvement in your welding when using argon, was this on thin sheet metal ie. panel steel ?
Barry, I know you are a big TIG fan for panel repairs, but unfortunately I have never used one and I believe there is a bit of a knack in using one.
I would love to do a course on how to use one but, my job has me away from home too often, so it is very difficult for me to do TAFE courses at the moment.
I also have have a workmate Greg, who used to work in the " hot shop" as a welder at Qantas engineering . Greg is also a keen hot rodder and has an immaculate "34 Ford coupe he has built , and is now building '34 four door. Greg was telling me it needed a lot of rust repairs .
I asked him what welder he used to repair the Ford , he replied " A mig" Barry, I then told him of your preference for using a Tig he was surprised , he said "They put a lot of heat in too you know "
He went on to say he is a big fan of Tigs but not for body repairs.
He also said if you take your time , and just make small tacks on the patches, and use a wet rag or he uses his compressor and air duster to cool the weld, and slowly join all the tacks together, distortion should not be a problem.
He also said the same with grinding just take your time and keep heat to a minimum. He also went on to say you wouldn't find many panel shops that would use a Tig to repair panels or even have one in the shop. Greg also said that Oxy's are not recommended at all to use for repairs on modern cars because of the steel they use for them now.
Barry, please don't think I am having a go at you , because your results speak for them self, nor am I saying my work mate Greg is the guru of all things welding , but I have seen his impressive results too.
I have also looked on the net about Tig welding and Miller (welding machine manufacturers) said that Tig welds are more malleable than mig welds backing up your claims . They also showed pictures of thin gauge metal welded by Tig which looked fantastic.
To cut short this log winded diatribe, I don't know if I can afford to justify the expense of a Tig or of my ability to use it, the Miller website said if you can Oxy weld ok you should pick it up fairly easily. I was pretty reasonable at Oxy so maybe...
Dennis one thing I do certainly agree with Barry is how good an Oxy set is , like you I let my bottles go about 4 years ago , I know the rent is a pain but the versatility of the " CIG spanner" is hard to beat. Once I get my shed built that will be one of the first things that will be going in it , after the Dodge that is .
regards Harleigh

Howdy Harleigh,

Its confusing isnt it !
Its all about sharing points of view and lessons learnt.
I think one thing that is agreed on by all is if you over do it with heat your in trouble so steady as you go.
As far as what type of welding technique used for body work it all comes down to personal preferance. Ive had alot of experience with welding thin guage stainless with a tig hence my preferance.
Your friend is right in his comments that the tig can put heat into the panels but I find the trick is with them you have to have your repair patch fitting perfect...no gap at all between pieces. I spend considerable time making the patchs fit perfect sometimes a whole day making one piece fit and tig weld with 35 - 40 amps thats all, minimal heat. A weld bead about 1.5 - 2mm wide. As with all methods as your friend says you still need to stitch weld if on a large panel like a door skin. Do abit about 3/4" long then hammer and dolly the weld.
If you blaze away with a tig at 80 amps then yes you will be in trouble.
The most forgiving method for home workshops is with the oxy. It can handle not so clean parent metal where as the mig and tig doesnt like dirty metal.
For a general user friendly workshop tool the oxy is the most verstile tool but you still have to know what your doing to control the metal.
Any old metal that is being repaired I use a little spot blaster first and get it real clean and I think that makes a real differeance to how hard the job is.
Once the metal is clean I try and use the spot welder to get tacks every inch or so and then join the dots with the tig or oxy.
The spot welder is limited to what the arms can reach but most of the time it works okay. Sometimes I will cut out more metal than I need to so I can get the spot welder arms in reach.
Im going to be doing some repairs over the next month so maybe I should take some pictures and post them.
The tig and oxy doesnt like modern sheet metal with zinc on it as you friend says but most of the metal we are dealing with is good old mild steel sheet.
Basil

Harleigh,
I haven't done a lot of sheet welding with the MIG, but welding with gas gets better flow in the weld on all surfaces. Like Barry says, the cleaner the steel and the tighter the fit then the better the welding.

The best advice I've has so far was from Blacksmith Pete. I told him about some of my worst attempts at welding and he said it sounded like I needed more heat. "But" I said "more heat in thin steel buckles and blows holes". "Well" says Pete, "weld faster so the steel doesn't get too hot"! Sounds simple, but I have found he is right - hot and fast can do the trick, especially if you've got clean tight joins. I'm sure others will have different advice, but at least you've all helped me see that its worth paying the price for the gas to go with the MIG I might also save up for an oxy set too.