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Hey guys. Just thought I’d give you all an insight on the procedure of collision repair and autobody refinishing.
I’ve attached a picture of the extended procedure, but will write out a few examples for you.
Most common: BUMPER DAMAGE, SCRAPES AND/OR SCUFFS AND PAINT CHIPPING
1) Remove plastic bumper cover. Dissassemble cover
2) Clean with wax and grease remover
3) Assess damage and sand out scrapes (Through paint into the plastic *GOUGES*) This will be done with a rough paper, likely 220 or sometimes 120 for heavy scrapes.
4) Apply a plastic friendly two part filler and skim one coat over the area, after sanding the surrounding area with 320 grit. Remember, this is just to fill in the plastic/sealer/base/clear you sanded out. You aren’t baking a damn cake, be easy with the stuff.
5) Sand out dried filler with 120 or which you prefer (Smaller jobs can use a higher grit, bigger jobs that reguire shaping need more coats and rougher paper to cut through it)
6) Apply a finishing putty. This is a lighter, thinner version of body filler. It is meant to fill minor flaws and hide a lot of the rough scratches. This can be finished with 320.
**Between each step it is good to blow off and clean the area with a de-greaser**
A filling primer needs to be applied to get the area ready for base coat and clear coat. The colour and clear surprisingly “fill” very little. They will not cover the sanding scratches. A high build, or sandable primer needs to be sprayed over the 320 grit sanded area and the repaired area. The primer is than blocked out with 320, and finished out with 500 (or +)
** Sand the area around the 320 sanding with 500(ish) 600 works too. 800 even. It’s all circumstantial and it’s hard to elaborate.**
7) When the primer is sanded out, and the finish looks good (wipe with water to make surface shiney. Look for any un-sanded primer or deep scratches, last minute dents or scuffs. Any waviness) you are ready to tape up and paint
8) Sand out the rest of the pannel (or in this case bumper) with 800 grit sand paper. Any chips or flaws can be dusted over with a little bit of colour.
8) After the car is taped up apply a two part sealing primer (Zero filling quality, used to seal any areas “burned through” when sanding out primer. Exposed metal needs to be sealed before recieving waterborne colours.
9) When the sealer is still slightly tacky, shoot one light coat of your waterborne colour of choice.
10) Slightly tacky first coat, apply a thicker second coat of base (colour)
11) Third caot, if needed
12) First light coat of clear
13) Second coat of clear, heavy as possible without runs
14) Third coat, again, heavy without runs
After the car has baked and is ready, pull the paper and pull the car into the sun to assess it.
***** A lot of the time, even the most up-most professionals use some sort of wet-sanding and/or polishing to achieve a flawless finish when repairing a vehicle. The finish doesn’t always come out flawless. The clearcoat “shrinks” as it dries and it’s very hard to get it 100% free of foreign particles.
After reassembly you are good to go, maybe a quick wash.
I will be writing more “professional” (and I use that term loosely) how-to’s on auto-body repair. I will include pictures too.
For now this was just a quick basic write up to give the average person the idea of doing even just a bumper repair.
*The porsche has just been sprayed with high build 2k primer. It will than be blocked out with 320/500 and ready for tape and sealer/base/clear*
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The first picture is of a 2008 Porsche GT3 Cup car (Sprayed with 2k high build primer, ready to sand)
The following pictures are of a early first generation Mazda Miata, being sprayed with an epoxy sealer, ready for base coat.
We actually used a single stage polyurethane paint on the Miata, it was more cost effective and the proper colour (solid red) could be achieved.
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