Every forum post I read and youtube video I watch usually recommend a basic wire brush and then some rust cleaner chemical to clear rust underneath before putting on undercoating. I never see anyone get under and go at surfaces with a wire cup brush like on the rear diff to make it shine or look fresh at least.Is these a reason for this? Would it be a bad idea to run a wire cup on some of the frame beams and larger surfaces like the diffs and stuff before applying undercoat? Or could running a wire cup brush till it's down to the metal damage some stuff?
if your car is that rusty then buy a new one
>>28710094I use a wire brush or flapper disc to remove rust all the time. I don't see why it would matter at all. I would suggest also using a rust inhibitor/converter as well to get into any spots you may have missed.
>>28710094Nothing wrong with cleaning up with the wire wheel. Remember though, that it polishes the metal, which paint will not like adhering to. Either sand it afterwards to etch it, or use acid as the other Anon recommends.
I wouldn't stress over minimal rust left on the surface as long as there's no grease or dirt, I mean you're going to paint it after all. Ain't no water or humidity getting to that metal again any time soon after that.
>>28710549If you seal rust inside paint then its going to rust from the inside out retard.
>>28710094>Is these a reason for this?most people aren't concerned about some surface rust, plus my engine oil pan, transmission oil pan, and diff cover all have a slow leak which gives my truck a healthy rust prevention coating 24/7.>Or could running a wire cup brush till it's down to the metal damage some stuffonly if you intend on leaving it exposed, if you're painting or coating it in some way there's no issue>>28710549you definitely need to remove all rust before painting you mong
>>28710976In what, 50 years? I can live with that. My car never sees rain or snow.
use a flap disc. its faster and better finish.
