Bodywork, how to fill/block sand

[djinuk]

Ok for any bodywork boffins out there im just wondering how you go about attacking car with dents etc. i am having to do a few small dents/bumps in the boot of my 205 gti. First i began by using a hammer to make any high sections, low sections, then i sanded the area back to metal and put down some etch primer, ive then filled the area and blocked it back best i can using 80grit and 120 grit. from 120 grit ive then just gave the boot floor a blast of high build primer out the gun which has gone on well however seems to be quite egg shelled, ive then given the floor a brief guide coat of matt black and began flatting back using a 400grade wet and dry and a block to show any remaining low/high spots, however its only a boot floor so im not after it perfect , but just better than it was.. where should i go from here as ive never took on bodywork on a large scale, should i flat back to 600 grade before paint or finer?

[wrightygtt]

everyones different, all depends on the paint/ basecoat, my final flatting has always been with a 1000 wet and dry prior to paint, I personally don't think you get away with anything lower 1.e 600 for waterbased paint. If your basecoat is solvent then you'll be fine with 800. Everyones different though, I know painters who never wet sand anything, to avoid moisture etc.:)

[djinuk]

ah cheers man, yea it appears there isnt a straight way of tackling it im using a 2k paint (white) direct gloss, so no clear coat etc so pretty simple stuff to spray i think. I think ill get it back to 1000grade before spraying. Thanks

[rs250nut]

With what your using you could go as low as 800, but if I have ever wet sanded stuff Ive gone with 600 and 1200. Go through it first with the 600 to remove the peel and then finish it with the 1200.If you had a d.a you could go with 400 discs, 3m super fine pads and red scotch. Make sure when you block stuff to do it at 45 degrees to avoid block marks and always go with what way the panel curves or otherwise you will create flat spots:)

Edit

If you finish your repairs on 120 the primer will shrink back after a while and you will see the repairs as a ring and a patch of coarse scratches, try to finish your repairs on 240 or higher personally I finish on 320.