Welding through painted steel.

admin

Hi, I will be installing a trunk floor in my project soon. I wanted to paint the steel floor with a corrosion resistant coating before I weld it in and cannot access all the hidden areas. Will I be able to weld through the coating to the frame?I was going to drill holes through the floor where it sits over the frame rails, then weld in those spots. The original was spot welded about every 2.5 inches. I was also going to coat the frame rails.
Reply:IMHO you should do your welding before you think about putting that paint on there.Drink a Guinness Draught....Millermatic 140Do you still rememberDecember's foggy freeze --when the ice thatclings on to your beard isscreaming agony.
Reply:If you do it with 6010/11 you will be fine, with MIG it can be done but certainly not the right way to do it.  I would try and find a way around it.Have we all gone mad?
Reply:Just wondering what kind of car? Welding a floor to the frame, sounds maybe like a Camaro with a subframe? Never heard of welding a floor to a full frame car! Just wondering.Flashhttp://flashracecarbodies.com
Reply:We weld through standard shop paint to tag on Stainless steel tags on carbon steel occasionally.Usually only when rushed and too lazy to grind! Works decent... Always done with TIG.Shop paint we use is more or less equivalent to rustoleom in a can.Not sure what kind of paint you'll be going through, or what process you have available.
Reply:Close...74 barracuda.Second pic is looking down into trunk. You can see the top edges of the frame rail. I'm finished removing it now and I have the rails cleaned up. I would like to coat them before welding.
Reply:this is the coating by eastwood, called encapsulator, probably just fancy rustoleum.this is what the trunk looks like, this one is actually not for the cuda, but close.
Reply:Oh yeah, I'm using a MillerMatic 130
Reply:Seems like you can get around it though-Paint the rails, paint the floor.Drill the holes for the plug weldPlace the floor back in, mark where the welding will be on the rails, pull the floor back out and remove the paint at those spots, grind away a little around the holes on the floor, put back in and Plug weld.dunno really-Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:thanks...that makes sense. What size holes should I drill and how far apart. The factory had the spot welds at about 2.5 inches. What about using zinc in the places I grind clean. Also, do you know what EDP coating is?
Reply:I know they make weld through primer but looks like ya can't just paint everywhere with ithttp://www.hotrodders.com/forum/thou...mer-84496.htmlEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Either stick weld it with a 6011 or paint it but leave about 3" unpainted along where your weld will be and then after the metal cools paint it thenWeldandpower 225Heliarc Rig for itTorchesect ect ectLifes Short WELD NAKEDLooking for a SA200
Reply:Weld it first, paint the gunk on after.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I weld through painted metal all the time, but I have a MM250, and I MAX the voltage out to blast all the paint away, and make sure the arc can jump through the resistance of the paint. You have a much smaller unit, and I don't think the voltage is capable of going high enough. Especially since autobody rust paints are heavy duty, high resistance paints.
Reply:You may want to consider whats in the paint and what kind of toxic fumes you may or may not have to deal with.Just a thoughtFelonCaution lurker lives here" hmmm That is serious,pass the ganja and pick up a  24 of MGD"
Reply:Problem with maxing the voltage out is on that thin stuff he will carry to much heat and have blow throughs.Weldandpower 225Heliarc Rig for itTorchesect ect ectLifes Short WELD NAKEDLooking for a SA200
Reply:Originally Posted by jroyster06Problem with maxing the voltage out is on that thin stuff he will carry to much heat and have blow throughs.
Reply:I've been working on my 66 mustang for the last 6 mos using a miller 135.  The weld through primers are junk.  I've replaced the trunk, trunk floor, full quarter and rear panel and the one think I've learned is clean metal and a good ground is critical.  weld it, then paint or primer it.   a dedicated 20amp, and .23 wire and 25/75 gas worked great!  pick up the eastwood plug welding pliers (#19134) and magnetic plug (#29935), they really help to prevent blow-through.