Mm251 ?

[GunLocators]

Got my new MM 251 from Praxair a couple weeks ago and have occasional clean arc starts. It seems to like to spit and sputter on start of a weld the immediately clears up. Any suggestions. The wire tension seems fine and I hold of 3/8" - 1/2" . It seems as if this is not a constant issues, just occasional. However slight a problem it is tons better than my old Lincoln HD3200 and the old Dinosuar 3 Phase Miller Stick machines in the shop.

[tackit]

I had trouble with my MM251 and all the trouble was due to cheap Mexican wire.

Other things to check: Metal is clean and does not have a heavy mill scale. Ground connections are tight, You have enough tension on the drive rolls. Your contact tip is tight.

[timw]

My guess is wire speed. Either too slow or fast, not sure from your explaination. If wire pushes away it's too fast.

[Scott V]

Got my new MM 251 from Praxair a couple weeks ago and have occasional clean arc starts. It seems to like to spit and sputter on start of a weld the immediately clears up. Any suggestions. The wire tension seems fine and I hold of 3/8" - 1/2" . It seems as if this is not a constant issues, just occasional. However slight a problem it is tons better than my old Lincoln HD3200 and the old Dinosuar 3 Phase Miller Stick machines in the shop.

Get into the wirefeed run-in and start with 75 % and see what happens.

[Danny]

The only poor arc starts that i ve experienced with my 251 have been on practice material were i tried to start an arc beside a weld that i just completed and hadn t brushed the soot off the basemetal left from running the previous weld. Besides the above mentioned occurance, I haven t experience any poor arc starts, and I've played with the run-in from 75% -100% with an .030 and .035 solid wire. If i remember right, i currently have the run-in set to around 85%.

[dyn88]

Im not sure if this will help you at all but I always cut the end of the wire before welding to ensure a sure start. I never thought it really matered till I started welding with 1/8 mig wire and if you dont have a clean end youll have a big mess to clean up .

[Danny]

Im not sure if this will help you at all but I always cut the end of the wire before welding to ensure a sure start. I never thought it really matered till I started welding with 1/8 mig wire and if you dont have a clean end youll have a big mess to clean up .

Yeah, I always cut the wire back to before every arc start too. I like to cut it at about a 45° angle.

[GunLocators]

I keeped the wire cut today and it seemed to help I had only a few poor arc starts.

[Danny]

I keeped the wire cut today and it seemed to help I had only a few poor arc starts.

Have you tried adjusting the run-in like Scott suggested? what wire size are you running? What do you have the drive roll tension set to? Do you have your spool hub tension set with a very slight amount of drag? Are you running the door chart settings or your own?

[GunLocators]

Yes Also running .035 ProStar , Drive roll tension if I recall is at 4 the spool hub is adjusted and the results are with door chart setting and running hotter lets say on 1/4" material 20.5 V 380 wire speed.