OK so I need to get some argon/co2 mix, I called my local welding supply and they offer a purchase of an 80 cu ft tank for 200 usd plus 28 for the fill, they say it is good for between 4-5 hours of welding...

now they have a bigger tank which I could rent, there is a 200 deposit plus I assume the fill the rental is nominal per month (I think under 10 bucks)

As I am doing a LOT of welding when it comes to the quarter panels etc I think I should go for the bigger tank, then once that is done I will buy the smaller tank for everyday use does this sound right? or will the 4-5 hour tank be enough? bear in mind I commute to work and the gas place is not open on Saturday should I need to refill...

2nd question, is the 75/25 mix the best mix for sheet metal?
I was recommended that I should use the smaller .023 wire.

any help or advice would be great...

 

I have a tank about the size of a scuba tank. It's not the smallest but it's was smaller than the ones we use in the shop at work. I've only had to fill it twice & I did a lot of welding in my rusty Northeast car. Keep an eye on the pressure gauge and you should be fine. Yes I use .023 which (I think) is the smallest you can buy. May sure you have a few spare tips and use the tip lube generously.

btw, I seem to remember that you have to switch the polarity when you go from flux core to MIG.

 

Thanks for the reply, the 80 cuft tank sounds like what you describe he said it was about 3 ft tall, I will be setting up the millermatic and leaving the craftsman as a fluxcore welder, I would sell it but who buys these things LOL.

I will pick up an extra tip or two, did you use the 75/25? I read somewhere about 85/15 but I have never heard of that? and any special type of wire?

 

In an ideal world--where almost none of us live-- I would have a quality 110V mig set up with 75/25 Argon; line feed, liner and tips for .023 just for sheet metal welding. Then I'd have a 220V mig set up as above for .035 wire for heavier duty welding.

If you can't have both, I think it is better to have a 220V capable of welding at least 3/8 material. With that, If you are doing a lot of sheet metal and intending to use .023 wire you may also need a different feed wheel and different liner in your hose as well as tips for .023. Ask the manufacturer or a welding supply place that sells your brand.

75/25 mix works fine for welding steel regardless of wire size and it is the most economical. More exotic mixes go up in price and straight argon for MIG is not recommended due to lack of penetration unless you turn the heat way up.

 

thank you sir, I believe my mig has everything for the .023, I will make sure.. Thank you for answering the gas question.

I really don't do enough welding for two machines but I agree a machine for heavier duty stuff like a rotisseree ( sp?) or even a body gantry would be great. I just need to get my sheet metal done, and funny enough the last time I did body fixes it was welding gas ( oxy acetylene) LOL... I used the flux core for the floor work which was minor, and it was just ok, but needed a fair amount of clean up to be made presentable, as I am doing quarters now, I want the best possible job I can do..

 

If you really wanna make nice welds with a mig, i can suggest to you this spot timer kit (if you have a Lincoln-electric Model).

I used this kit with FLUX CORE wire (yes, sheetmetal with flux core) and it worked perfectly. I consider it a really good 100 dollar investment if you're doing alot of sheetmetal.

I'm not saying it's not doable otherwise, but, it makes it easier if you can't get a good timed feed with your trigger finger.

http://www.amazon.com/Lincoln-K2525-.../dp/B001I1WHJW

 

I use 80/20 mix gas for welding carbon steel. The 80 cubic foot tank lasts longer than you think. The 4-5 hours is of continuous welding and when you weld quarters, you do one little spot at a time. This about a one second weld, so the 80 cubic foot tank should be more than enough to weld quarters and then some. If you haven't bought the welder yet, get one that has the infinitely adjustable amperage. It makes dialing in the weld a lot easier.

 

hey Thanks for the tips, My Great Wife bought me a millermatic 140 for my birthday, and believe it or not I have yet to take it out of the box ( been busy making undercoating, dirt, paint fly LOL) and I have just lowered the body on the frame, so ready to start doing repairs...

I also managed to pick up an excellent condition hypertherm max20 plasma cutter

it is amazing how clean the cut is with this thing, but I may just go cut off wheel air chisel spot weld cutter.... we will see.

 

The 140 is a great welder. I have one set up for stainless and love it for thinner metal.

 

Did you use the auto set or just tuned it by 'ear'

 

I used to have a Hypertherm Plaz that I lost in a fire. Now I'm using a Miller. The Miller does a thicker cut for about $600 more than the Hypertherm. But, Hypertherm are one of the best in the industry.

 

I just tune it by feel. For stainless, I use tri-mix usually at about 25-30 cubic feet per hour.

 

If yoy cut with the plas be sure to grind the cut to remove the carbon as it will interfere with your weld.............tom

 

Thanks for all the tips went to the welding supply picked up the 80 cuft tank the big tank was really big the size of my oxy acetylene tanks so no room, picked up a spool of .o23 some tip lube and I think we are good to go.

Tom thank you for the tip on the plasma will do that

Man getting excited, well took a vacation day today so better get into the shop and do stuff :-). Thanks again fellas