The Mitsubishi Pajero Owners Club®

[Simon_W]

I am attempting a 'rattle can' paint repair job on the rear wheel arches of my Mercedes. There were a few rust bubbles that I wanted to fix before they got worse. It's metallic silver, with a clear coat over. I'm working to a crease line in the wheel arch, so I am planning on making the new paint blend in on the crease which should minimise any small colour difference.

I've de-rusted, primed, filled, and smoothed off the repair. The final abrasive paper I used was 3000 grade, which has left a matt finish on the surrounding clear coat. If I apply a damp rag to the matt finish, it glosses over instantly. There are no deep scratches at all.

So two questions for anyone with experience of this type of project:

1. Do I need to polish the matt finish out of the clear coat before putting the new metallic paint and clear coat on? In other words, will the new clearcoat hide the matt finish?

2. Should I rub down the metallic finish before applying the clear coat, or is it best to leave it as it as sprayed?


Any advice much appreciated. Thanks.

[Google]

[peteinchad]

The matt finish is what "keys" the new paint onto the old paint.

My dad used to call it "flatting off" and did it to every car he was repainting - and he did dozens because he had his own repairs garage.

I wouldn't flat off the metallic base coat before putting on the clearcoat - but some people do.

[Simon_W]

Many thanks Pete! That's exactly what I wanted to hear.  

I'm really pleased with what I've done so far and didn't want to screw it up with the final finish. This is could be heading for my first-ever decent DIY car paint job. I've never had enough patience in the past.

[peteinchad]

I love spray painting - I find it very satisfying to make something look like new. It does help to have patience with it though  

[h4rri]

I used to love spraying then I attempted to colour change a car and it was a disaster Rattle cans are a pleasure to use though and you can get great results if you take your time.

My top tip is take your time, don't be tempted to rush anything and when it's had enough paint, stop. There's always the next day and getting a run out because you wanted to pop another coat on takes ages


Good luck

[Simon_W]

[peteinchad]

I've still got the scuffs on the bumper corners to do on mine - previous owner obviously couldn't drive such a big vehicle.

I have got a HVLP spray gun LIKE THIS which is better than rattle cans - I find the paint is too thin from an aerosol.

[Simon_W]

[h4rri]

I use HVLP from a compressor fed gun and a couple of smart repair guns.

They are great but use a lot more paint and they are more difficult to control unless you are comfortable with them.

A lot of the issues I experienced were due to spraying on the drive though

I still prefer the control of a rattle can for smaller repairs. Less hassle mixing paint and cleaning gear afterwards too

[peteinchad]

Yep - the drive is not the best place - and why does every insect want to walk on the wet paint??

[Simon_W]

One of the problems for me is how to blend the paint across a panel. If you use masking tape you will always see the line, and if you don't then the overspray looks a mess and seems to get larger and larger.

A mate of mine is a modeller and does a lot of painting. I was explaining the problem to him, and he said that modellers use a piece of cardboard held away from the actual piece to act as a paint shield. So there's a kind of shadow effect at the edge of the sprayed area. As with camouflage, for example.

Something like this:



I've cut a large piece of cardboard out to match the shape of the wheelarch, and will space it off the bodywork with some foam pads. I've done some experimentation, and so far so good.

[peteinchad]

I tend to just "mist" it over any joins between paint - although the cardboard idea would work.

Best if you can finish the paint at a panel joint - but that is more time, more work and more paint.

[The procrastinator]

[mick_n3]

[Simon_W]

The method has worked really well on the wheel arches, where there's a natural crease to hide the paint change.

I've also been experimenting with a hole cut in a piece of cardboard and spraying through that to restrict the amount of overspray. So far, so good.