I'm working on my Ranger fixing some dings and rust. I just wan't to know some tips and tricks!
go light on the hardener :D practice a bit before you get too carried away
Put it on thick and smooth it out with one of those plastic ser things. Once it dries, sand it smooth. Easier than a drunk girl on prom night.
Oh, before you apply it, try to get all the rust off and use some sort of rust converter. 3M makes some stuff that works pretty good. It makes the repair last much longer.
I always prefered to apply it over bare steel (you can argue for days about that) rough up the steel with 60-40 grit by hand and spread it on. Dont spread it any thicker than 1/4" if you need more than that then you will have to hammer and dolly it into shape first.
All the rust preventative in a can stuff is pure shat dont waste your money on it, use an angle grinder carefully or a die grinder/dremel to get in to the pits. If your just stripping paint or light surface rust a soft bristle wire wheel will take it off nicely but watch you dont heat up the steel too much or it Will warp.
One last thing only mix as much filler as you can use in about 5 mins, once it starts stiffening up it wont spread nicely and it wont stick aswell.
Just play around with it and you'll get the hang of it
Also corrugated cardboard makes a good mixing board and is disposeable but margarine container lids can be bent and the filler will fall off and you can reuse them a couple times.
On my car I had some big holes in my rear quarters behind the rear wheels (after I cut out all the rust). That area is tough since it's a concave curve. I tack-welded patch panels in the holes and bondoed over them. It's not perfect, but it's better than a lot of bondo jobs I've seen.
Sandbast all rust to clean any pitted metal otherwise your wasting your time. Even a cheap siphon feed blaster from Menards will do the trick. Make sure you get a good quality filler. 3m suff it good and napa carys some good stuff to. Bondo name brand is not the best in my opinion.
Bond brand body filler is , dont touch it. I prefer motomaster professional filler, mainly 'cause I scored a gallon for half price cause it was dented :D
Go to a parts store and buy something decent if you want it to last.
clean it with wire wheel or sandblaster...then use a rust convertor *IE SEM rust-mort, or rust shield*, epoxy primer, or self etching primer *SEM has this in green,black,gray*. then use thin coats of body filler...be sure the spot is clean from dust/dirt so the filler don't get contanimated (sp?)...rough up the primer a lil before apllying so it has something to "bite" on...if the metal is a lil weak or has pin holes, try a fiberglass reinforced filler. then put a primer sealer on...then base coat/clearcoat if you don't go single stage
make sure u do a heavy first coat then slowly sand it down, but make sure u allow it long enough time to dry or ull **** it up. i know im 14 but i do alot of body work, i did my 1973 honda cl350, and my dad 1968 harley sportster. main thing is take ur time and it will come out awsome