MIG Welding Metal Prep
Gary SimpsonDescription
Often overlooked, welding metal prep is key to achieving good-looking and strong welds with proper penetration. Metal fabricator Gary Simpson explains the importance of properly cleaning metal and demonstrates how to remove mill scale to create stronger welds.
Metal prep is important to make sure that you remove all the contaminants that are gonna possibly contaminate your weld, creating a weak, porous, or brittle weld. So, from mill scale, rust, paint, anything that could potentially contaminate your weld, you need to get it removed. We're gonna go ahead and show you a couple examples here. We got a piece of quarter inch here that has some mill scale on it, it's just how, when metal is processed, it automatically forms that scale, but, in order to achieve good welding penetration, you know, you do need to remove the mill scale on even new steel, and if you're repairing, or working on older, or used parts, you know, removing paint and rust, you got several examples of how you can remove that, you know, the most basic, wire brush, wire wheel with the drill, this is rust buster wheel that I have on this grinder, and also you can use, and also you can use, you know, 36 grit, 50 grit grinding discs, this is a Roloc disc, to remove paint, rust, and scale from your welding areas. Before starting, always important, wear your safety glasses. Cover your hands, and make sure that you have good control of your grinder, and make sure that you have good control of your grinder, anything that could potentially injure you, you know, make sure you're covering yourself and giving yourself a sacrificial layer. Right here is a piece of quarter inch, and we're just gonna remove the mill scale. So, this is clean bare metal, this is the mill scale, you get the idea, and this is just an old used piece from an air cleaner, but you can see rust, paint, that's not a good surface to weld to, so, simple. Again, clean, ready for welding. Again, clean, ready for welding. Surface consideration for cleaning your metal, if it's oily or greasy, go ahead and use a solvent like lacquer thinner to remove them before trying to grind it, other words all you're gonna do is smear on the oil, and then you're just gonna end up with contaminated welds. So, a fast drying solvent like lacquer thinner works best, remove the oil and grease, then go ahead and grind your metal. Then, fitment is key, Then, fitment is key, whether you're doing a butt weld, or a tee joint, whether you're doing a butt weld, or a tee joint, or a fillet weld, making sure you have got fit or a fillet weld, making sure you have got fit is key before you start welding.
What about respiratory protection? Just as important as eye protection. Also run grinder oriented going off edge of metal. His method of going onto the edge can catch and damage the disk. You need to realize some people watching these videos need all instructions to be correct not just vague recommendations.
Do you have a prt number & where you purchased the rust buster wheel on the grinder in the video?.
Please leave a product number of tools used on clips. Where to get RustBuster and product number used in this clip? I hate mill scale removal!
In terms of surface preparation for welding, does sandblasting adequately prepare the metal to weld? I know that “metal in white”, freshly blasted metal, is usually ready for priming and painting, but should I grind the welding surfaces after pieces come out of my blast cabinet? Thanks, Tim