mark schoening
Active Member
OK--I'm a klutz! on tail, flush set slipped and I now have small dent next to rivit. Wait to paint time or ? I can't think of a fix.
PainterJohn said:All of the "heavy" fillers work best (and should always be applied) to bare metal, besure to sand the area with atleast 80 grit before you wipe it on there, otherwise it will flake later on.
KTM520guy said:If you fill it make sure you sand the area your working on REAL good. Most RVs that I have worked on that have had some type of fill work done to them have not been sanded well. Not sanding correctly will lead to the body filler popping off. I would suggest machine sanding with something in the range of 36 to 100 grit.
KTM520guy said:Yes, you do have to be very careful. You want to get past the point of being lightly scuffed but stop well before the point of sanding a thin spot in your skin. Using tools like die grinders and disc sanders is a good way ruin a good skin panel. Use a DA (dual action) sander for best results.
gpiney said:The one thing no one has yet mentioned is that you should never use any Polyester based product. Bondo is polyester based. The reason for this is that it will shrink over time. Your best bet is to use West system and microballoons.
az_gila said:KTM250guy(?)
I'd be interested in a test case measurement of your technique. It would be easy to do.
Use your DA sander with 36 grit on some 0.032 alclad, and then sand (no burnishing allowed) with a finer grit until the alum. surface is taken down to the bottom of the 36 grit sanding marks.
Then use a micrometer on the test piece... I would think you would be under 0.030 at that point, extremely close to the limit.... 0.002 is not very much metal removal.
gil in Tucson
szicree said:I think I'd like to hear from a filler manufacturer what grit is recommended for prep, and whether or not primer should be applied first. I'm sure they test this stuff for adhesion under various prep methods. Also, 36 grit and a DA on .025 skins (or even .016 elevator) sounds pretty scary to me.