First off, thanks T_Bone for the soldering info on galv sheet steel. Got those funnels made with little trouble. Clamps I normally use for welding were acting like a heat sink for the solder which proved a disaster. After tossing the first one to the scrap barrel, I used 3/32" steel pop rivets to hold the joints on the following ones. I toned down the muriatic acid as you instructed with the cut scraps of the galv steel. Wiped the joints areas with the flux prior to the pop rivets and then wiped the rivets too. Used 50/50 solder with the torch mounted iron, sealed the joints and rivets quickly and easily. Worked like a charm and I thank you for your time and knowledge on this one!OK, question on steel pipe, sort of following the discussion earlier on steels. For years I have used only three local pipe suppliers, all of which only carried Sawhill brand pipe with it's disticntive yellow/white colored print. Never had any problems with this brand. The last couple weeks I was doing some sub-contracting pipe work for a local HVAC company installing 4", 3", 2.5" and 1.5" sch 40 gas pipe. I had no trouble with the Sawhill brand 4" and 3" however, the 2.5" and 1.5" was not the same brand. I could not find a name on it, the only marking was a meduim shade blue stripe with a circle shaped stamp every so often in line with the stripe. I could not make out anything inside the circle clearly but it appeared to be and "R", "P" or something similar. No other markings at all. The ID of the pipe was rough with lots of scale. The 2.5" nominal required welded joints. I was using Hobart brand 1/8" E-6010 rods for the entire job from the same 50# can, oven kept on site at 150F. All joints were ground clean and made with 3/32" open root, ground between passes. Every joint with the 3" and 4" went perfectly. When I got to the 2.5", the first joint welded fine but the second had a blowout. I cut the joint back 1.5" on either side of the weld and started over blaming the blowout on myself being tired and the location of the pipe between a roof truss and light fixture. Re-welded that joint without a problem the following day but had the same type problem on four more joints on the same pipe as the day went on. Doing these joints with the pipe hanging in spot from the roof, 27' up, I continued to blame myself for the problems. The last section of the 2.5" pipe ended up being about 4' long tee on the end reduced to 1.5" on the run and 1" on the branch. Since welded joints are only required on the 2.5" and larger dia., I welded a short nipple on each reducer. The nipples were cut from the same brand pipe as the 2.5". I did the tee/reducer/nipple welding in the shop and saw what my blowout problem was. It blew out at the seam in the pipe. I was able to saw cut the weld and visually inspect it finding a large spot of what appeared to be a slag inclusion. Started to think either I was loosing it as a welder or something is wrong with this pipe. I cut 6" off the same lengths of 1.5 and 1" pipe that the nipples came from and saw cut along the seam. I found numerous spots similar to what I found at the weld joint blowout. Seeing this, I immediately contacted the HVAC company and informed them of the problem. We agreed that the only safe thing to do was to replace all this brand pipe. Completed all the replacement yesterday and not one problem using the Sawhill brand. While discussing this problem at the HVAC shop last night, a foreman from another job site complained about a high rate of thread cutter breakage on the same brand pipe on his job. We have yet to find out a mfg or brand name for this problematic pipe and if anyone has had similar problems or knows what brand this is, please speak up. Thanks,
Mark Kw
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