Review on Stainless 3 5 Mandrel Bend Elbow by Jonathan Germain

The quality seems normal judging by the dimensions. Not great but okay. The third photo shows it's not 16ga as advertised. I deduct a star for that. The nominal thickness for 16ga is 0.063" and as you can see in the photo this material is 0.050" thick in some places. To be fair I went down to 0.060 in a few places. It's also possible that the metal finisher who polished them just overdid it a bit. The fourth picture shows the inside of the 2.5 inch piece. I cut the 304SS into an adapter crimp and the seam looks exactly as it should. This piece measures at least 0.060" at its thinnest point and approximately 0.063" at its thickest point. Well within factory tolerances for this material. This tap seems closer to 18 ga than 16 ga. I took off another star because the part is clearly not being bent by the mandrel. It still has a fine finish on the inside that hasn't been marked by any tool other than the die they used to mark the part number before they formed the sheet metal blank into that part. The only functional disadvantage of mandrel bending these bends is the strain on the outside of the bend, which will likely reduce the 16ga to about .050 inches on the outside of such a small radius. The inside of the bend is of course compressed to a slightly thicker dimension. And finally they lost another star when I saw welds burn out at the seam. They either have to clean these things or use a different substrate when welding them. because acid condensate in your exhaust will soon start working on the oxidation in that seam. For physical reasons, the outer part of the bend always receives the lion's share of wear; but if your exhaust system has any back pressure at all, the seam will still come into contact with the corrosive elements in the exhaust. If they were bent with a 2.5 inch tube mandrel you would see the radial tool marks inside the tube being pulled over the mandrel with tremendous force and the seam would be clean and would fully penetrate the laser seam with no oxidation, like the straight tube in the fourth photo. And the seam won't be as perfectly centered on the inside radius because it's never a good idea to compress the seam in a tight bend. It will most likely be oriented at an angle of about 45° from the inner centerline, since that is where it will experience the least bending stress. and in most cases throughout its lifetime. I should mention here that I am a *pipe bender* welder/fitter. We bend steel, stainless steel, aluminum etc. on a mandrel every day. It takes a long time to set up a bender that tight radius on 2.5" stainless steel and I would probably throw away a few yards of expensive material during the setup. Even wholesale prices are going up lately, just material, that could have cost me as much as I paid for those finished parts. That's the only reason I ordered them instead of bending them myself. No bending shop in the States could sell these elbows at this price and keep their doors open. , unless they offset losses with higher-margin products. I have been welding and fabricating in a variety of industries including aerospace and marine for almost 20 years. These strains would be immediately rejected by any qualified QA personnel in any of these industries. and a few others. After all. I would recommend these arcs to anyone looking for a low radius arc in this material for a non-critical application. The seller just has to be honest about what they are and how they are made. They will fit most automotive exhaust systems, but anyone looking for a header for industrial applications or something that requires stringent quality control should look elsewhere. I only use them for the exhaust system in a resto mod project so they work great.