Original Posted By: "Mike Luther"
No one really asked but this was one of my big unknowns going into thisprojectso I figure I would put this out there so others can get an idea what Idecided to use for welding the fittings.Welding. I'm NOT A PRO OR CERTIFIED WELDERI use a Victor (clone) type welding torch ($375 with kart and tanks). It'sbeen fine for most of things I have welded. I purchased 40cf Oxygen andAcetylene tanks that last meabout 6 months to a year depending on the amount of practice welding andfixing stuff for the neighbors. I would not recommend smaller tanks. As fortips, I have one each of the 000, 00, 0 tips ($20 each) and they have workedout fine. I used the larger tip to heat metal for bending andsquishing but I really should get a rose-bud tip for this purpose. Thesmaller 000 worked great on the thin metal but mostly I use the 00 size. Ihave trouble welding 1/4" plate to 1/4" plate with the tips I have.I use mild steel rods as these are recommended for 4130. I do not removethe brass coating on the rod but I think I will in the future as I have readit might be bad . I read that your a not supposed to use 4130 filler rodunless you are post heating welds (Finch welding book) (post heating shouldnot be confused with stress relieving with the torch). I recently pickedup some ER70S TIG rod, as I have seen this discussed as a good gas rod aswell as TIG rod.I recently purchased a Meco Midget torch body ($115?) and a full set of tips(only 8 buckseach). I have not used it yet but it's tinny and cute. I saw itdemonstrated at an air show and it seemed to work fine. Nice and small andeasy to hold. I have trouble with holding the Victor in the right place attimes. One thing to watch out for with this torch is my Victor has flashback arrestors built into the torch body but the Meco Midget doesn't. So Ihad to buy separate flashback arrestors (another 40 bucks). Also the hoses are smaller so I had toget reduces (20 bucks) and hose (25 bucks).I use the plane old gas-welding shade 4(?) lens. I can't afford the nice$100 dollar ones. I have yet to find a good fitting pair.Finches Performance Welding book is a good reference.EAAs welding book and video are ok.BRAZINGThink of brazing as gluing two pieces of metal together with another metal.You only have to heat the base metal hot enough to melt the brazing rod (youdon't melt the rod in the flame). Contrary to what some believe, brazing isnot necessarily weaker then welding. If you use the correct braze materialit can be stronger then the base metal. As I understand it, 4130 does notreact well to brazing because the braze gets into the crystalline structureand can cause cracks when it cools. Not a good thing. So I weld all my 4130fittings.For what it's worthChris Tracy.Sacramento, Ca----- Original Message -----