big mike 13 #51 Posted May 3, 2010 Spool guns can weld aluminum,steel or stainless.They mostly are used with aluminum but could be used with steel to get you 30 feet from the power source. I cannot remember how long between hydro tests on high pressure cylinder is because I hardly ever look at test dates on high pressures or acetylene.On propane we check every cylinder as part of the pre fill check list. Share this post Link to post Share on other sites
