Newbie MIG question.

[roger55]

It's my first MIG. I have had it a few years and don't use it very often. It's a 120 Volt Lincoln 135 SP 135 Plus. I've never re-filled the 80 cf gas bottle yet.
I've used it a while today and it looks like I'm getting low on gas. It's at 750 lbs.. Looks like it is going down kind of fast now.

Is that enough to do much welding? Or, is it not enough left to be worthwhile and I should take it and get it re-filled now?

 

[stricht8]

What are you welding? That amount could last a while. If you refill it now you will pay the same price regardless so you might as well use it up.

 

[arkangel06]

750lbs is still alot of gas dont change it till its EMPTY.

 

[roger55]

What are you welding? That amount could last a while. If you refill it now you will pay the same price regardless so you might as well use it up.

That might be why it dropped a lot today. I was welding some 3/16" brackets on a car frame. I had it going full-blast.

The next stuff I have to do is body sheet metal and will have it set way down for that.
I'll go ahead and use it until it's empty.

Thanks guys.

 

[zmotorsports]

750 lbs. is still quite a bit of gas left. You will pay the same for a refill whether there is some left in the bottle or not, you might as well get all your money's worth out of one bottle before purchasing more.

What do you mean you had it going full blast. What do you have the flow set to? You should only have the CFM set to around 17-19 CFM unless you are welding in a drafty shop of outside where the air/wind can remove the gas from the molten puddle while it is solidifying, then just turn the flow up a little at a time until happy with the results.

Also what mixture are you using? I recommend a C-25 (75% argon/25% CO2) mixture rather than straight CO2. I feel you get a better looking weld as well as much less spatter. The C-25 mixture is a little more money but well worth it in weld quality. Mike.

 

[roger55]

750 lbs. is still quite a bit of gas left. You will pay the same for a refill whether there is some left in the bottle or not, you might as well get all your money's worth out of one bottle before purchasing more.

What do you mean you had it going full blast. What do you have the flow set to? You should only have the CFM set to around 17-19 CFM unless you are welding in a drafty shop of outside where the air/wind can remove the gas from the molten puddle while it is solidifying, then just turn the flow up a little at a time until happy with the results.

Also what mixture are you using? I recommend a C-25 (75% argon/25% CO2) mixture rather than straight CO2. I feel you get a better looking weld as well as much less spatter. The C-25 mixture is a little more money but well worth it in weld quality. Mike.

Oops. I the Scfm was set to 35. I set it when I got the welder and I read the manual then but don't know if 35 is where I set it or if any kids might have turned the knob. I need to read the manual again since it has been so long. I just don't weld enough to remember this stuff.
Yes it the argon/CO2 mix.

What I meant by full blast was the amperage all the way up which is J on the adjustment. I had the wire speed on 8 which is what the guide says to do when the amperage is set on J. It was welding pretty darn good.

If 17 to 19 is where I need to be, I'll re-set it there.

Thanks. Glad I posted.

 

[Jack Olsen]

I go anywhere between 12-20 cfm in a shop with the doors closed. There's no benefit to wasting gas.

 

[KenS]

"...don't know if 35 is where I set it or if any kids might have turned the knob."

I hope kids aren't playing with that high-pressure gas valve.

 

[roger55]

I hope kids aren't playing with that high-pressure gas valve.

I hope not also. But I don't think so. I close the valve pretty tight and I've never forgotten to turn it off and I've never found it on. Kids are not in my shop very often. But, I bought the welder about 4 years ago and that's a lot of time for me to have not re-checked the pressure.

I just looked at the manual.
Here's what it states:

If using a regulator with an adjustable flow meter, close the gun trigger and adjust the flow to give 15 – 20 cubic ft per hour (CFH) (7 – 10 L/min) [use 20 -– 25 CFH (10 – 12 L/min) when welding out of position or in a drafty location for CO2]. For argon mixed gas, trigger to release gas pressure, and turn off the adjust the flow to give 25 – 30 CFH (12 – 14 L/min).

Seems like they recommend higher than what you guys use for the CO2/Argon mix. This is not written very well though and easy to misunderstand.

I might have looked at the L/Min scale by mistake when I originally set this thing. The bigger outer scale is the metric one and the inner small scale is the English. I suspect I just assumed the English scale would be the large one. Doing that, if I set it at 17 L/Min thinking I would go between the 15 to 20 recommendation, that would have set it at 35 Scfh when I thought it was 17. However, I still would have misread the instructions since they recommend 20 to 25 for the argon mix.

 

[roger55]

Well, I ran my bottle almost all the way down and traded it out for a full one.

I've been doing a lot of sheet metal work lately and already have this bottle down to 1200 psi. It started out at 2000. Was that what they normally fill them to?

 

[gregsz-28]

Should be filled to 2250 psi, but that will change with air temp.

Well, I ran my bottle almost all the way down and traded it out for a full one.

I've been doing a lot of sheet metal work lately and already have this bottle down to 1200 psi. It started out at 2000. Was that what they normally fill them to?

 

[mkdive]

I usually set my CFM to around 15...(working in the garage with doors closed).