i am a former professional welder-there are myths and sayings but heres the facts from the oregon structural enineers union-in my words
yes there are fumes-weld in a well vented, or fan blown area
you can weld structurally if you remove the galvinized coating at least 1/4 inch from the weld surface
if this is done on both surfaces-strength loss is minimal if present at all
and in my opinion, if you have to do it, so be it-but non galvanized is easier
yes it will hold paint if prepped normally-although it will always look like ass IMHO
i used to weld galvy plate to galvy pipe for pile driving type situations, then houses sat on em-so yes it is plent strong- but if you try to weld without removing the coating- it will leave voids, pockets of gas and air, and not pennetrate well, resulting in a poor quality weld
hope that helps
And x2 on the ventilation. If you don't ventilate well, you can get very nauseous, and get some pretty bad headaches. I'm sure there is long term effects as well, but I don't know exactly what they are.
My sliders are made outta galvy, work just fine, plenty strong and durable.
