Flap disks for alum.

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Hey could I use this to prep edges of aluminum I want to weld? I havent seemed to get the stuff to weld properly and I think some of it is from my prep. I wanted to know if you guys think these will help me out in the prep dept. http://www.lehighvalleyabrasives.com...Special/DetailMiller Diversion 165Rage 2 Chop saw
Reply:The thing that would concern me about those wheels is...  "Contain a calcium stearate coating that liquefies under heat" . That sounds like it will leave a film of something on your aluminum. It's possible that an acetone cleaning will remove it, but who knows? A good clean SS wire brush is hard to beat.
Reply:A coarse file or aluminum burr works much better.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:what kind of file? a steel file?Miller Diversion 165Rage 2 Chop saw
Reply:I use a standard red 40 grit flap disc all the time and I have no problems, but I do brush it off with a stainless scratch brush after just in case. I dont know if that makes a difference. The 40 grit flap disc can take down some aluminum pretty fast too, works like a grinding wheel.
Reply:I'm familiar with stearated abrasives from woodworking, but not for aluminum, but the concept should be the same.  They add it to keep the grit from loading up, but the residue can interfere with the adhesion of water based finishes, so I suppose it could interfere with welding too.Still, just a wipe of the wood with a mineral spirits soaked rag removes the residue, so I believe an acetone cleaning (which you should do anyway after grinding) should leave you sparkling clean.Personally though I'm more of a fan of carbide burrs for prepping aluminum, than abrasives.
Reply:been using the red rolox disc for 20 yrs and i too brush with a SS brushand have had no problems ( except for the nasty ol cast props )on heavy welds i like to use the burr and like some others use WAX to keep from loadingidealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:The biggest problem with using any high speed abrasive (even wire wheels) is that they can smear the oxide and contaminants you are trying to remove into the aluminum to a point where no amount of brushing will adequately remove them. You could try a red scotch brite pad but your best bet is to prep by hand and finish with acetone.
Reply:Originally Posted by ironmangqThe biggest problem with using any high speed abrasive (even wire wheels) is that they can smear the oxide and contaminants you are trying to remove into the aluminum to a point where no amount of brushing will adequately remove them. You could try a red scotch brite pad but your best bet is to prep by hand and finish with acetone.
Reply:yeah  what steve said most is what is done in pre prep to weld  if you use a hard disc to grind be light-lite  (dont bear down )its all about being clean. ---idealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:If you have to do any amount of bevelling use a router with a bevel bit, works great.....Mike
Reply:there are cutoff, grinding and flap discs made specifically for aluminum and they work like a charm.  Unloader
Reply:Fastenal blackstones , 5.01 best ones on the market.I forgot how to change this.