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Just a quick question... I might have to build a custom i-beam for my pergola (as the snow made the spand bend and I need more strength). How well does galvanized in a can hold up compared to normal galvanized via other processes (however they do it). Is the spray on stuff as good as the other (factory)? I just don't want it to rust and stain the deck and stuffIt will be about a 16' spanThe Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man" Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:I work for a metal buildings company and the best we find is when we send it off to be hot dipped. We fab up the beams, weld, drill holes and then send them off. I think we have tried every brand of galvanize spray and the rust still comes through after a while.
Reply:Originally Posted by cajun welderI work for a metal buildings company and the best we find is when we send it off to be hot dipped. We fab up the beams, weld, drill holes and then send them off. I think we have tried every brand of galvanize spray and the rust still comes through after a while.
Reply:if you can't/don't want to dip i think a couple of coats of the good old brush on aluminum paint still works better than any spray. mikeOl' Stonebreaker "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:You'll be better off to send the beam in to be dipped. This is the best I've used for repairs. Heat the base metal, rub the galv stick in the heated zone, and wire brush in. Attached ImagesDont pay any attention to meIm just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Good topic, I've been wondering whats good for repairs. Thats nice of CEP to put that on there. I used some stuff that seemed pretty good once, I've been kicking myself for not remebering what its called or how to get it. It was a two part mix. A solid piece of material that looked like a snickers candy bar. You took the bar and dropped it in a quart of liquid that came w/ it. You smashed up the bar and stirred it to mix it. Then you brushed it on. I think I remeber having to mix it quickly, the stuff started to thicken and setup quick. It was given to me by my boss in 2001 to do a repair. It would be helpful if this sounds familiar to anyone. It wouldnt surprise me if it were outlawed to the public for environmental reasons. Anyway, like everyone says, sending it to the galvanizer for dipping is probally the best. Expensive though. The ones I've used charge by the weight of your material , just under .50 cents per lb, and that was on fairly big jobs too.
Reply:I like the melt on gal for repairs. Spray on wont be as good as hot dip ( as you know ) and will usually require recoat but will last longer than epoxy paint.I know you have a 16' span, so i would go hot dip.
Reply:I have had super good luck with a brand of epoxy paint "tnemec" its expensive but if u brush it on u can beat it with a hammer and it just sorta deforms a little . Thats if hot dippin is to expensive lol , maybe u can buy a beam already galved ?I forgot how to change this.
Reply:Originally Posted by LawsonWeldingLLCI have had super good luck with a brand of epoxy paint "tnemec" its expensive but if u brush it on u can beat it with a hammer and it just sorta deforms a little . Thats if hot dippin is to expensive lol , maybe u can buy a beam already galved ?
Reply:Hello,A good question to ask. Preparation is very important.For Hot Dip Galvanizing all weldments must be 100%. There can be no open seams or crevices on the a part to be dipped or it will be rejected. Go here American Galvanizers Association (AGA) for a wealth of information on the topic. There you can also search for local facilities with listing of the tank dimensions at different locations. Please read up, improper preparation that slips past inspection is hazardous to the operators.Cold Galvanizing does work well if applied in layers at proper temperature, humidity and time intervals to achieve a durable thickness. One thick coat does not work. The stuff in a spray can, not to sure about that. Brush on applied correctly will outlast you if not applied on a wear surface.Good Luck
Reply:Some good brands of spray on galvanizing do exist; they are fine zinc powder suspended in a one part epoxy paint. As with any paint, they need proper surface preparation to adhere well, and usually, two or more coats do increase protection. Since the zinc particles don't touch the metal, their action in protecting the metal isn't the same (or as good) as the hot dipped method, under the worst conditions; under good conditions, the difference might not matter. I'd suspect Utah weather to be much better than that of Louisiana or Florida where both the humidity and salt in the air even corrode Unobtanium!
Reply:Thanks for all of the replies. I checked around and there is a place within an hour drive that will hot dip it for me. They normally charge .50 / lb with a minimum $200 charge, but said that if I wasn't in a hurry they would just charge me $100 and throw it in another batch that didn't fill their baths.The Lord has declared, "This is my work and my glory--to bring to pass the immortality and eternal life of man" Moses 1:39Link: My name is John, and I am a member of The Church of Jesus Christ of Latter-Day Saints.-- ColdCreekWorks.com --
Reply:Greetings:Thermal Spray is an alternative to hot dip galvanizing. Both are processes that apply molten zinc metal to the surface of a what you want to protect. There is portable thermal spray equipment that uses oxygen and acetylene to create a flame in a flame spray gun. The thermal spray gun feeds the zinc wire down the middle of the flame where it is melted. Compressed air atomizes it and you spray it just like spray paint.Just as in galvanizing, the surface must be prepared properly for it to stick. In thermal spray, that means no oil or grease on the surface, and a grit blast to "white metal" look. If you do that, it works great!The US Navy has been using it for many years on ships (mil spec 1687) to fight corrosion.If you would like to read a short article on comparison of the two, go to:http://www.reneuxit-thermal-spray.co...lvanizing.htmlBobThe Thermal Spray Guy
Reply:Locally there is little cost difference between a blast and epoxy coat compare to hot dip galvanizing. A good galvanizing job will last over 100 years especially away from the ocean. Be mindful that water coming off galvanized material could stain a bit initially. A truss under a roof is pretty safe from that I would think. I have found zinc rich paint painted on a wire brushed surface is quite good. Brushing is important since it wipes across the surface of the metal. When you spray, the paint is deposited on top of any contamination.
Reply:Another alternative is zinc-chromate self-etching primer. Its probably not available everywhere (like Kalifornia) but I have found a source in Maryland (Kalifornia's cousin to the East). It can be purchased on-line from various boating supply places.Historically this has been the spray on galvanization of choice. It is sometimes tinted to look red and is often used on beams in buildings.Careful, zinc-chromate is a chemical, not a color. Some sell paints that are zinc-chromate in color, but don't have the chemical properties.On clean metal, with no scratches, it will outlive you. If the scratches aren't to deep, you will get rust on the scratch but the surrounding metal will not rust.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:Hot dip galvanizing is the real deal. Cannot be done at home.But you can get spray on products like Cold Galvanize spray to DIY.Many kinds.AWS certified welding inspectorAWS certified welder |
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发表于 2021-9-1 00:21:44