optimized spool gun procedures for aluminum

[OscarJr]

After bird nesting my Millermatic 100 spool gun 25 times trying to weld .035 wire with a .030" tip I was about to list on eBay. I finally bought some .035" tips and didn't bird nest or ruin a tip in 2 hours working with the gun. Probably 40 minutes of welding. In summary if you use .035 wire use .035 tips.

Yup, I've used the appropriate size tips in my spoolmate150 and didn't have any issues, thankfully.

[aametalmaster]

Glad it worked out for you guys...Bob

[old jupiter]

Been watching this with interest, since I rarely use my spool gun, and need any pointers I can pick up. Bob, this is NOT, repeat NOT, to argue with someone (You) with substantial experience, but do you understand about all the raised eyebrows at your ".030" tip for .035" wire" suggestion? Presumably the others, like me, have seen more than one printed recommendation to use one-size-OVER tip with aluminum because it expands more than steel when it gets hot. Bob, I'm certainly not trying to get you to hedge your advice, or make you repeat it endlessly, LOL. I just feel that with interesting experiences like yours, you might have come up with some ideas as to why your findings are opposite to other advice we're getting. In any case, I'm going to do my own little tip-size tests next time I run the gun (though I don't look forward to having to clear birdnests from my Traffimet!).

Oscar mentions tolerances, and I understand that one issue people are having with Chinese welding wires (which I don't buy) (so far as I know) is that they often don't hold wire diameter to acceptably tight tolerances. This is also true of contact tips, and unfortunately it's not easy, maybe not possible, to know where these were made. Maybe some of the problems that occasional users have with their spoolguns are coming from this cause. Maybe I should be hand -feeding tip-drills down every contact tip to affirm actual diameter . . . ??