Aluminum prep before welding on Extreme 4x4 ...

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On the last episode of Extreme 4x4 they focused on aluminum welding. They showed the use of a stainless steel brush to remove the oxide and then sprayed on a cleaner and wiped it down before welding. They didn't say what the liquid was ... maybe the liquid manufacturer did not pay for advertising ... who knows ... but I am wondering if anyone on here might know what it was?Thanks,Arvid
Reply:I have no idea..I use a stainless brush and acetone myself.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:yup..UA Local 598
Reply:likely just electric parts cleaner or brake cleaner.
Reply:Originally Posted by TSORlikely just electric parts cleaner or brake cleaner.
Reply:Here's the link to the episode.At 4:30 into the video he covers how you can use a SS brush to remove the oxide layer or you can do it "chemically". http://powerblocktv.com/video/?ep_nu...-14&ep_show=XThttp://all-a-cart.comWelding Cart Kits and accessories
Reply:BTW, he can't run a spoolgun for sh!t.http://all-a-cart.comWelding Cart Kits and accessories
Reply:Originally Posted by ZTFabI don't think so. I just watched the clip form the episode and he doesn't say what it is but he applies a chemical from a spray bottle and it removes the oxide layer.
Reply:Originally Posted by TSORI just sent Ian a PM
Reply:Personally, I use a flapper wheel that uses 80 grit sand paper on a 4 1/2 inch angle grinder.  It takes about 10 seconds to do a long stretch and you need almost no post clean up, such as acetone.  Obviously using this method you need to be a little quick with it as you don't want to severely gouge the metal if it's going to be seen.  I've used a lot of acetone but recently I started using 99% rubbing alcohol.  I think acetone is overkill for a majority of the time and you can keep rubbing alcohol in a plain old plastic spray bottle.  This method seems to give me very clean welds in a very short amount of time.  I am lazy.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands.  If you want to know why, click here.Buy American or bye America.
Reply:Originally Posted by TSORlikely just electric parts cleaner or brake cleaner.
Reply:Originally Posted by TSORlikely just electric parts cleaner or brake cleaner.
Reply:Originally Posted by TSORlikely just electric parts cleaner or brake cleaner.
Reply:Originally Posted by ZTFabBTW, he can't run a spoolgun for sh!t.
Reply:pinjas,Maybe that's the problem you're having with "arc blow".  All that silicone you're imbedding in your aluminum with the sanding disc.You using the same sanding disc to prep your tungsten?Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:DO NOT USE BRAKE CLEANER AND WELD OVER IT!!!!! A lot of people do but the fumes produced from the arc and the chemicals interacting WILL KILL YOU.Go hot, or go home!
Reply:Aluminum Oxide forms in a few seconds, so the SS brush will remove the film but it likely reforms before you get the arc lit up. Brushing DOES scarify or create rows of oxide and the AC in TIG will lift them all, and the hot argon or helium argon mix will flush them off the puddle.  In MIG a hand brush before the weld is started is usually enough to get under the oxide and the gas cleans ahead of the puddle.If the parent metal sits for longer than a day the film will of oxide evidently gets deeper than 2mill heading toward 3 to 5 mils depending on moisture around the plate/sheet/extrusion.  So if you brush before MIG the disruptions will allow the oxide to float off the puddle quicker and if you're using the AC TIG arc the current oscillations will lift the oxide so the cover gas can expel it.Hydrocarbons begin to leave a carbon black film when heated so the solvent cleaners are to get the greases, oils and lubes off the parent metal.  I'm with the Zap on acetone and have been for about 40 years, lots of boats and it works reliably.I think MIG clean up is more critical than TIG and I've acquired the habit of being excessively clean about TIG prep.   But I don't use the acid etches - like hydrofluoric acid- to clean for welding because the newer power supplies have arc control that produces near globular transfer (very nearly TIG-like droplets instead of spraying) so the oxide film is overcome and lifted away if you simply mechanically abrade the oxide.We don't use sanding or grinding to clean weld zones but we do use SS tooth brushes or if possible 4" wire wheels if the wire is 0.014" or less in diameter and 'soft'.  Heavier wires (designed for use in welding SS alloy materials) leave a melted, smeared area that will often cause excessive porosity because of the large amount of oxide film 'mixed' into the smeared or melted parent metal surface.Aluminum oxide and mill scale both hold moisture content in ambient shop conditions (maybe not in Arizona?) and therefore increase the hydrogen entrainment of MIG welds.  But taking the oxide off with acid before welding requires cleaning up the acid etch- so we use the 'dry' methods, acetone (fully evaporates) followed by the ss power brush to remove mill scale and all welds are SS tooth brushed in the few seconds before the arc is lit.Cheers,Kevin Morin
Reply:I think the spray he used in the video is Aluminum Cleaner and Brightner.I don't recall the brand name of the last stuff I bought. It was yellow. I tried it when plating a walking floor trailer. It is suppose to be rinsed and gives off an weird odor if you don't. I imagine it was some type of acid. In the end I used flap disks and acetone. The floors had way too much corrosion to get through by hand with a wire brush.
Reply:this aluminum cleaner is yellow. Attached Images
Reply:Originally Posted by deucedj22DO NOT USE BRAKE CLEANER AND WELD OVER IT!!!!! A lot of people do but the fumes produced from the arc and the chemicals interacting WILL KILL YOU.
Reply:Thanks for all the responses. It looks like we have a "likely candidate" and hopefully the pm that TSOR sent will get the final answer.As a side note, though I agree with the general tone of TSOR's comment ... Originally Posted by TSORum.. ok I'll add that to the list of the other 462 things in my shop that can kill.common sense people.
Reply:If I track back thru the MSDS sheet I end up thinking the Arcair product is this product under a different label.And again, it looks a lot like what was being used on the show.Given that I think we have identified the product, can anyone suggest how well it works? It doesn't seem to be all that expensive ... under $15 a quart ... and the non-flammable feature may be of value in the welding shop ... may not make it onto TSOR's 462 list ... but does it work as well as acetone or 99% alcohol, etc.
Reply:Aluminum cleaner is probably a caustic, or acid that breaks down the aluminum oxide.    Safer to weld over than chlorinated brake cleaner type products.  But still nothing that you want sitting on bare skin any length of time.I've always found that wire brushing with a clean SS brush was enough for me.  I'm with Zap though, if there's grease to remove.  Acetone from the Paint section of Wallymart works just fine.  I've used rubbing alcohol in a pinch too.  Doesn't work quite as well or evaporate quite as fast.  If you need the ultimate in clean, and you can get it, then petroleum ether will take off most any oily residue.  It's much more flammable than acetone, so you really need to be careful when handling it.  Static sparks will set off pet ether fumes.Another option in the states that allow it to be sold is everclear liquor.  Its just about pure ethanol, and leaves very little residue.  I worked years ago with electronic service techs who used everclear to clean components and electrical contacts and such.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Originally Posted by arvidjThanks for all the responses. It looks like we have a "likely candidate" and hopefully the pm that TSOR sent will get the final answer.As a side note, though I agree with the general tone of TSOR's comment ...... there does seem to be actual incidents out there ... Common cleaners can turn into phosgene gas to offer just one but google can provide more ... to suggest that brake cleaner fumes may be much better at killing you than most of the other 462 items in the shop and that common sense would say "just don't do it". After all, phosgene is listed as a chemical weapon. True, not a very good one, but being on the Chemical Weapons Convention Schedule 3 list is probably not be an honor shared by a lot of the other 462 items.Based on the information here Phosgene it appears as though the UV from the arc is what creates the phosgene. I will speculate that the heat simply accelerates the process.As TSOR suggests, common sense is all that is necessary to avoid any problems.
Reply:Originally Posted by SundownIIIpinjas,Maybe that's the problem you're having with "arc blow".  All that silicone you're imbedding in your aluminum with the sanding disc.You using the same sanding disc to prep your tungsten?I'm curious what the magical ingredient of the spray on aluminum cleaner is, also.  I've tried a few acids that I think can be ruled out, unless I was somehow not using them properly (left on for too long, or residue not cleaned off properly?)  All when left on for long enough will react with the aluminum and aluminum oxides, leaving a whitish looking surface that is quite hard (won't wash off with water or petroleum solvents) and they also don't really "TIG clean" (leaves black "soot" like contamination around the weld area)  * acetic acid / white vinegar: works in days, leaves white etch "coating" without dissolving parent aluminum material  * phosphoric acid / metal cleaner type product - works in hours, leaves white etch "coating" and maybe (would be very slowly) dissolves parent aluminum material  * hydrochloric acid / muriatic acid, concrete cleaner - works in minutes to remove the oxide layer, once it breaks through that seems to work even faster (bubbling reaction) dissolving the parent aluminum.If you ever oxy acetylene weld aluminum, you will quickly learn what type of preparation leaves aluminum oxides behind, and what doesn't.  The best solution I've found so far has been mechanical, specifically one of the plastic abraisive impregnated products - "nonwoven" scotch brite type pad (I've used die grinder powered discs), or machine powered abraisive plastic bristle cup brush.  Both of these options do leave residues that need to be washed off (like wiping with clean rag with some strong petroleum solvent) before welding.  Still searching for the "chemical" aluminum oxide cleaning solution (which would be handy for spots you can't reach mechanically...)But yeah, AC TIG with adequate heat, and good gas shielding does seem to do a really good job, at least where you can get hot enough and on the front face of the weld where the shielding cup is.  Still would be useful sometimes I feel to clean off dirty backside of weld chemically (where you can't reach this area mechanically) to keep junk from bubbling up when you penetrate though to the back side of the weld sometimes.  I've also encountered nasty stuff in aluminum castings before too... mechanical methods I found effective for cleaning those were dental scalers to reach into deep crevices, or carbide burr on air grinder to just remove the whole pocket (to be re-deposited by TIG with fresh filler rod)Last edited by jakeru; 08-23-2010 at 05:10 PM.
Reply:Sanding discs are fine to use on aluminum. I do not use liquid cleaners unless I have grease or something smeared on the part. I just sand, or even nylon disc the part. Just don't leave black melted nylon wheel marks. Ha-ha. A fellow just dropped something off here tonight to be welded. I found it when I got home. I do not even know who it was. But he had drilled a hole and prepped the surface of an aluminum oil cover. The poor guy probably broke the pilot drill in the hole saw and gouged the surface pretty nicely. I just welded it up and took some pictures. Pays to buy the cobalt pilot bit. Ha-ha. What ever he used to clean left some black stuff in the area he ground. I just ran a very fine nylon wheel over it. But I did not burn the wheel or heat the part. I just scuffed it up. You can use any method you like as long as you know what and why you are doing it.It looks like they surface anodize the part after they weld it. It is not really any type of real coating. It just kind of shines up the surface and welds a bit. I just laid it on the table and welded it. I did not even clean a spot for the ground. So it is not the traditional anodizing found in my area. There is no way a ground clamp can attach to heavy anodizing. You have to grind a spot off to get contact. I did not even clean off the inside of the part. I just welded right over the coating. But it is what it is. If someone wants what looks like an aircraft part I will setup backup gas and have someone follow me with a trailing cup. If you look at the welds on that part they are thought out well. So that they come out nicely. But where they start and stop or meet another weld, they are a bit sloppy. And there are even some black gouges. On the inside, the welds often do not penetrate the part. Or even weld the joint on the inside. So it is what it is.        Sincerely,             William McCormick Attached Images
Reply:I was reading about aluminum prep materials recently and came across an aluminum treatment called "Alodine" also called "Alodizing".  It's converts a thin layer of the aluminum on top to some sort of Chromium containing substance, increasing corrosion resistance.  Supposed to be electrically conductive also.  Alodine 1001 is a clear version that can be applied over polished aluminum.  They also have a golden colored version of Alodine.  Maybe that is what was on the top of that valve cover, William?http://www.aircraftspruce.com/menus/...psupplies.htmlInteresting reading about the Alumiprep and Metal Prep products also.
Reply:Originally Posted by jakeruI was reading about aluminum prep materials recently and came across an aluminum treatment called "Alodine" also called "Alodizing".  It's converts a thin layer of the aluminum on top to some sort of Chromium containing substance, increasing corrosion resistance.  Supposed to be electrically conductive also.  Alodine 1001 is a clear version that can be applied over polished aluminum.  They also have a golden colored version of Alodine.  Maybe that is what was on the top of that valve cover, William?http://www.aircraftspruce.com/menus/...psupplies.htmlInteresting reading about the Alumiprep and Metal Prep products also.