Tough time keeping a puddle going

[redmule1154]

Has anyone else used the Maxstar 150 with little success. I see that recently there is a run of these hardly used machines for sale on Ebay. There has got to be a reason they are being sold right after they are bought. Hope to hear some of your opinions on this machine. I was given the suggestion to come to the tig site. If you had not seen my post on general questions. I learned on 330P miller with water cooled torch and then bought a 150 but could not keep a puddle going. I would move forward with the torch and filler and after about an inch I would lose the puddle and have to back up. By the time I finished with my run I had a very wide and ugly looking bead. Went back to the 330 at work and had no problems So I don't think its me. Thanks.

[villemur]

Is there any way that you could have the polarity reversed on the machine? The symptons that you describe sound like what you could get running DCEP (reverse polarity). I've only gotten to try a Maxstar once, and it was an older model, but it ran really nice.

Let us know what you find out.

Tom

[weldgault]

The difference could be between the 300 and the 150. You will have to slow down. also, more info would help. John

[redmule1154]

To Weldgault:The Miller 330P with the water cooled torch is a 460v 3 phase unit and the 150 was powered up with 220 v single phase power. I was welding 11 ga CRS sheet metal (Brand new) The inside corners were the more noticable, then the lap joint and finally the butt joint. I tried such things as slowing down, that was my first thought but that did not seem to effect it other than making the puddle wider and higher profile. With both units I was mainly using 1/16 tungston with .045 rod. I tried using the 3/32 tungston with no luck either. They both were set up with a foot pedal control. I was running DCNP. That was the second thing I checked after having problems.

[Rocky D]

I agree...it's not right.

[villemur]

I don't think the problem is the switch from the 330P to the Maxstar. The Maxstar is a good machine, and DC welding is pretty straightforward. Sounds like you could have a problem with the machine.

What are you doing about gas coverage? You must be using a torch with a gas valve on it? What's your flow set at? Do you have any pictures of your welds that you could post?

[redmule1154]

I set the gas from 15 cfh to 22 cfh and found that it was the best at 22 cfm. I tried to post some pictures but it keeps telling me that the upload of the files has failed. Don't know what the problem is. If I can figure it out I will post the pics. Well the people here on the help line edited my picture size so they could be down loaded on this site. Which they also did for me and told me how to do it in the future. Great Help Line. The first two pictures are with the 150. The second two are the 330P. My camera is not the best on close up shots, hope you can make them out enough to see what I'm talking about. Wide and clunky.