252 popping

[T Red]

I have a 252 that I cannot find an answer for. Tweco gun. It pops often. I have cleaned the ground connections. Changed the liner. It's really bad at start. Once you get a puddle started you really have to stay right in the center of it to prevent more popping. .035 wire, usually run about 20 Volts, 350-400 ipm. I also have a couple of 251's that weld great, same settings, same steel. Any help is appreciated. Tim

[Danny]

Have you tried increasing your voltage. 20 volt seem a touch low. If you haven't tried it yet , try giving 21 -22 volts a try.


Also, you have adjustable run-in that you can try playing with, if needed, to possibly help improve the quality of the arc starts.

[johnnyg340]

I second Danny's suggestions. Spot on.

[T Red]

Have you tried increasing your voltage. 20 volt seem a touch low. If you haven't tried it yet , try giving 21 -22 volts a try. Also, you have adjustable run-in that you can try playing with, if needed, to possibly help improve the quality of the arc starts.

Yes I have tried quite a range of voltages. The higher voltage helps a little but does not seem to be the problem. I run two other 251's at 19 V with no problems. What is the run in speed? Is it just the wire speed at the start of the arc? If so I still have problems even after running a bead a while. Sometimes it gets worse. I feel like there's something wrong with the machine. I'm going to check the lead connections on the welder itself. Thanks, Tim

[T Red]

I spaced out my paragraphs in the above post but the forum software puts them all together. I'm I missing some setting?

[gnforge]

252 popping

Check your ground, make sure hv good clamp, and good ground wire and connection at welder.

[Danny]

Have you checked that the V-groove on the lower drive roll is aligned with the in let and out let guides?

[Danny]

Try installing a gun off one of the 251 units onto the 252.

[T Red]

Have you checked that the V-groove on the lower drive roll is aligned with the in let and out let guides?

Just checked it. No problem there. I'm going to switch guns like you suggested. Thanks, Tim

[tackit]

When my 251 started popping on starts I called Miller....they told me to take the hot start wire # 8 (yellow arrow ) or a # 79 wire off the contactor.

My 251 would pop and weld the wire to the tip almost everytime the trigger was pulled, removing the wire seems to have helped quite a bit, but it still will pop on occasion.

My 2003 251s' best looking beads are when it's in spray mode using 98/2 gas with .030 SuperArc® L-56 ER70S-6 wire. 99% of the time 1/2" steel is the thickest I ask it to weld.

I thought of putting a toggle switch on the machine so I could switch the hot start feature ON and off, but I'm getting lazier by the second and just about ready to pull the pin.

[walker]

Just because one machine welds good with the wrong settings doesn't mean another will. Your voltage meters are likely inaccurate on one or both machines. Start by turning down the wire speed until the popping or stuttering stops, then you are in the ballpark. What thickness steel are you welding? Your wire speed indicates 1/4" but your voltage indicates maybe 1/8".

[T Red]

Tackit I may try that.

Just because one machine welds good with the wrong settings doesn't mean another will. Your voltage meters are likely inaccurate on one or both machines. Start by turning down the wire speed until the popping or stuttering stops, then you are in the ballpark. What thickness steel are you welding? Your wire speed indicates 1/4" but your voltage indicates maybe 1/8".

I always assume the meters are inaccurate. I have tried many settings and still have problems with this one machine. Mostly welding 11 ga to heavier steel.

[walker]

Try setting it at about 320 ipm and 21 volts. That is appropriate for the weld you are trying to make.

[T Red]

Walker I have tried that and many other settings.




I switched guns and that solved the problem. I don't understand why.

[T Red]

Update The 252 is still popping too much even with the Miller 25 gun. Also it has a noticeable rumbling sound at lower voltages. Which is also when it pops. Tim