Welding with CO2?

[86bobbedtoy]

15 seems about right with my lincoln 180hd 220 with co2

[superyota]

The main thing with straight co2 is that you tend to run higher nozzle pressure.  I run 30-35 with argon and 45or more with co2.
Hey Eddie give me a call.  I might have a large c25 bottle you can pick up pretty cheap.  
Looks like I wont be able to afford KOH this year since its gonna cost around 200.00 for fuel + food ect.  

I get off work at 4 today.  I'll call you as soon as I get off.  That would be great!  Talk to jrock, he is heading right by you on his way to KOH monday afternoon.  Thanks again

[superyota]

15 seems about right with my lincoln 180hd 220 with co2

I have a millermatic 175, 220v.  I'll try it out and see how it works.  It would be nice to get a larger c25 bottle so i'm not filling up every week.  When using welders at work or at the 4x4 club(using c25), I always run it at 15psi, which drops to about 10psi once the trigger is pulled.  I have no experience with co2 though. 

[94MtnYote]

Too much pressure can cause porosity too, it can cause turbulance and suck in air.

This is called the Venturi effect. 

[Sparkplug]

I have a millermatic 210, and i run my co2 at around 25 in no wind, and 35 if its windy. My welds turn out fine.

[junya92toy]

Too much pressure can cause problems, but so can too little. Biggest thing of too much, is you waste a lot.

[yota4x4sc]

I run 15-25 psi
never seemed to help to have more pressure, except if Im welding out in the wind

i run 12 to 15 psi with argon.. my welds come out perfect..only need more in wind sometimes

[superyota]

got a chance to finally use my welder with the co2 this last sunday to weld up total chaos a-arm stiffener on a buddies truck.  the co2 actually worked a lot better than i was expecting.  a bit more spatter, but I think I can deal with it for now.  I still would like to trade out one of my co2 bottles for a c25, just need to wait to find the right one.

[yota4x4sc]

most weldin stores will trade u out for free..ive dont it a few times before

[superyota]

yea, i went to air gas, but they wanted to trade me out for a c-25 bottle that was smaller than my 20# co2 bottle.  I want to get a bigger bottle, not sure on how they are measured, but i've seen ones that stand about 4ft tall and about 6-8 in. diameter.  they had one at airgas they would trade me for, but they said i would have to trade in my 20# co2, pay $100, plus another $45 for the c25 gas to fill it.  so trade mine in and pay $145 didn't really seem worth it me.  i'll hold out til i can find someone looking to trade me straight accross.

[junya92toy]

Gas blend cylinders are "measured" for the amount of gas they hold, for the amound of co2 you get from 20 pounds, you would want a 160 cubic foot cylinder.

[superyota]

the  one they were going to trade me for was a 80cu ft.  any idea how long that would last?  i use my welder almost every weeekend.  probably don't weld for more than 5 min. combined total of welding.  i just don't want to be filling a 80 cu ft bottle every other weekend or so.  i run aroun 10-15 psi, depending if i'm indoor or out door.

[junya92toy]

well 80cf, and if welding at say 20 cfh, you could weld for 4 hours.

[superyota]

wow, that doesn't seem bad at all.  maybe i will trade for it.  any idea what the price difference between a 20# co2 and a 80 cu ft bottle is?  are they pretty much the same, or would I be better off trying to sell my co2 bottle and buying c25?

[junya92toy]

Personally, I had a 150 cf argon and It seemed like I was always filling it up tig welding so I stepped it up and got a 330cf cylinder and I have a 50 pound co2 cylinder, the bigger the cylinder the better the price is. i was paying 16-20 bucks for 20 pounds of co2, the 50 pounds is about 30-35. argon was like 60 for the 150 cf

[blackdiamond]

Here's a little additional information on welding.

Some of you are talking about partial penetration welds (i.e. fillet welds and many other types of joints).  These welds can be sized to be 100% efficient which means that the joint has equal strength with the thinnest member that is being joined.

A full penetration weld generally requires a bevel to the root and a backgouge where the opposite side of the joint is actually ground to remove all slag and porosity before welding.  In this case, a butt joint could be ground smooth with the surrounding plating and still be 100% efficient.

I'm an engineer in an industry where many of the welds are either X-ray or ultrasonically inspected through the entire thickness.

[junya92toy]

It is usually acceptable to have 1/8 renforcement on groove welds.

[blackdiamond]

It is usually acceptable to have 1/8 renforcement on groove welds.

Based on what standard?  I'm not saying that you're wrong, just that it all depends on the application and require weld strength.

[junya92toy]

D1.1 and D1.5 to start with, and pipe welding, high pressure vessels too. 1/8inch wont reduces the strength, anything over can yes. Depending how far its bent.

[blackdiamond]

D1.1 and D1.5 to start with, and pipe welding, high pressure vessels too. 1/8inch wont reduces the strength, anything over can yes. Depending how far its bent.

Pipe welding isn't something that I'm involved with.  I do the heavy structural stuff and let the mechanical guys deal with their system piping.  I'm most familiar with MIL-STD-22D for joint designs.

[junya92toy]

Im certified for structural(d1.1) and bridge(d.15)

[Hyena]

So much overthinking going on in this thread.

[blackdiamond]

So much overthinking going on in this thread.

You're probably right, but the Navy submariners are very greatful that I care about welds.  It's a very different world than roll cages to be sure.

[junya92toy]

Well if ppl would get over their egos, they could learn a little too.

[yjay]

Im certified for structural(d1.1) and bridge(d.15)

May I inquire what one must do to be "certified".

[junya92toy]

I for d1.1, I have all position cert. SO that means, I passed a groove weld on open plate with a backing strip, doing a vertical up weld and then a over head weld. They test plate, is then cut to get 2 pieces called a coupon. they bend the root pass and then the face 180 degree bend to see if it cracks or breaks.

The d1.5( bridge) is set up the same way, but the whole piece is x ray before testing. Including all of your starts and stops.
I have a stick, fcaw in d1.1
stick, fcaw and submerged arc in d1.5

You have to keep the weld 1.8inch over the top of the plate when finished. Anything over is a fail anything under the plate surface is a fail

[emsvitil]

May I inquire what one must do to be "certified".

And I bet they'd be purdy welds.................

[junya92toy]

Well, if they arent, its a fail, cuz you will have slag trapped, undercut, lack of fusion and thats all gonna make it fail