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jayhawk
10-08-2004, 12:17 PM
I'm working on taking out and filling 20 year-old hail dents and it's going along pretty well. On the fender arches tho, I find myself having difficulty keeping the arch in the few dents on the more severe curves of the top of the fender-- I keep sanding them just a little flat with my sanding block (flat on round!) and then having to refill. It's not really that noticeable but a) I know certain folks who will find any imperfection and b) I will be one of them after the paint goes on! Any tips from those of you more experienced? Thanks!

Stinky
10-08-2004, 02:08 PM
I've seen guys use a paint stirring stick with sand paper wrapped around it. the paint stirring stick will give you a bit if flex, and still maintain a firm and flat surface to sand with.
Plus they are usually free /ubbthreads/images/graemlins/smile.gif

I'm sure if you went to a paint supply shop they probably have a "Special" tool for this purpose.

I'd try the paint stirring stick first.




Hope this helps

Rick O.
10-08-2004, 02:44 PM
I'd buy one of those sanding sponges and wrap your paper around it. The sponge is hard enough not to collapse, but soft enough to follow contours. They are inexpensive and available at most auto supply houses or even Wal Mart.

trrdster2000
10-08-2004, 07:26 PM
Jay, one way is to buy the 18 inch flat sander, spray the primer with a different color primer, really just fog it from about 2 feet away, don't cover it, (darker shows up better). Then work mainly up and down the fender not back and forth. When the darker color primer disappears you are smooth across that area, a couple of times will make you a pro. Wayne

Trevor Triumph
10-08-2004, 10:00 PM
I've had success by using a sanding block or sponge and moving the block at a diagonal across the curve of the surface. When looking at the curved surface I could see the progress better if I looked down on the fender rather then trying to look head on. T.T.

jayhawk
10-09-2004, 12:39 AM
Thanks, gents-- FYI, I've tried the sponge/paper idea and it works better than the solid block but it is just a little too soft and takes more off other areas than I need.
I like the primer idea to show what you've done and the cross/up and down strokes may work in all but the double curved areas around the top. I also dug up an old rubber block that is about 1/2 inch thick-- it may provide some arch yet be firm enough to just take the high spots.
Wayne-- not sure what the 18 inch flat sander looks like-- is it just like the block sander or is like one of those that look like a plane with an handle? Thanks again
Pete/Jayhawk

BOXoROCKS
10-09-2004, 12:14 PM
Take it a hair low then build it up with hi build primer several inches either side of the crown. Long board sand in a shaving motion from the fender lip up to the flatter section of the main fender. Starting at the front to back of the arch. You will be using the edge of the long board to do this. DON'T follow the arch front to back, sanding parallel to the fender untill you get the shape right.Prime several coats again. Then sand with a hard pad diagonally over the arch with the proper grit. Pretty hard to explain but will come to you after some practice.

trrdster2000
10-09-2004, 02:47 PM
The long block sander is the long one with the handle, works really well on flat a surface or working rounded curves. A lot of good advise here from the build up of primer to which way to work the curve. Just find out what works best for you. Are you using wet and dry with water and a couple of drops of dish washing soap in the water, helps keep the surface and paper from getting oil off you hands. Be sure to use a sealer like BarCoat. It will prevent the paint from bubbling up from under your primer, as all paints are not compatible. You use this stuff right out of the can, no mixing. Wayne

jayhawk
10-10-2004, 09:24 PM
Well, I've been practicing my lessons and it's going well. Using primarily a 12" long 3/8" thick piece of rubber with wet or dry sanding paper for the curved sections. I can flex it along its length or width and have been working it (I think in the directions suggested more up and down or diagonally over the crown of the curve-- last sanding is lightly horizontal (with the paper slightly arched along the contour) to finish. The filler/primer is doing its work and it's really nice to see and feel the result after the 400 grit paper. Got only two little places to finish on the rear of the car and then move to the front.
One more question-- In the past, I've brought the car to the paint shop after a 400 and 800 grit sanding but someone said I should use 1200!? Seems to me the 1000-1200 is for between coats of paint? Pete/Jayhawk (Hawks own this weekend)!

trrdster2000
10-10-2004, 09:53 PM
Jay, if you use 800 or 1200 on the primer the paint will have nothing to grab hold of, 400 is fine and don't put a brand new peice on the car, rub it on some other surface first. All paper tends to have some large stones or whatever on the surface. 1200 and 2000 grit are for final before buff out. Wayne