Spraying Bumpers.

[Beaker]

Well I will be wanting to spray some plastic bumpers soon, and I would like to have a go myself and learn whilst Dan is doing welding on my police car.

Just wondering if anyone could put together a how to along with materials needed for me, being a novice I don't know.

We have a compressor, and a spray gun. Just need to purchase a mask. Oh and we don't have that much space either :(

[Jack]

When it comes to painting and trying to do a proper job, it's all in the preparation. Sanding, primering, sanding some more and then a little bit more sanding is the order of the day.

I would suggest taking the bumpers off and mounting on a stand of some sort. If your area is dusty, consider making a painting "booth" with plastic sheeting hanging from the ceiling.

Huge books have been written on painting cars so you're unlikely to get complete information from the forum.

One last thing - primer, colour, laquer - don't forget the laquer - this is what gives the paint job depth and shine (and separates the excellent paint jobs from the reasonable ones!).

[B18 GPC]

Just a note :

KKWs plastic bits were very dull. Out of wondering... erm.. Curiosity i sprayed the blastic bits in clear laquer.. they now look the dogs.. Just a tip , if you ant be botered with too much work .

Also , i have some gunn things that are good for holding the can you pull the trigger and it sprays , ive found my spraying has improoved since i got these.

[Miracle maestro]

A lesson I quickly learned when I started spraying was to make sure no moisture ends up in the gun.
You'd be surprised how much damp there is about -even on the driest days.
Always drain the compressor well before spraying, and give the pipework a good blow through, and last but most important of all fit a good water trap filter in the airline between the compressor and spray gun.

When spraying start with the edges first, because these need most paint. Then lightly spray the entire item several times with light coats always doing the edges first and finishing with the flat work.

Just a couple of tips that I had to learn the hard way.

have fun ;)
Darren.

[Maria]

Flat whole bumper with approx P180 (dry) disc (or paper if you don't have a DA sander and don't mind losing the skin on your fingers). Get into the crevices round the rubbing strip with sandpaper. Flat harder if there are any light scratches. Make sure the edges of any more sanded areas are "feathered", ie blended into the surrounding area rather than a hard edge. If there are any deep scratches, fill with normal body filler and sand down with 180s then 320s (dry). Again, feather the edges of any filler into the surrounding area.

Give the whole panel a good rub with some panel wipe / degreaser, and make sure you wipe it off again thoroughly as any residue can "solvent pop" through the paint. If you have a tack rag, use that to remove any remaining dirt and dust.

A good-quality aerosol of plastic primer will be very useful at this point, and save a lot of time and effort. One light coat will do. As soon as it's dry, you can apply some high-build primer. If you don't want to spend ages flatting out irregularities in the finish, mix with slightly more thinners (eg 50% rather than 30%) than you would normally which will make the primer go on smoother. Spray the edges of the bumper first, as you can go over any overspray on the bumper face afterwards. If you do the face first, the overspray from the edges will show.

If the finish isn't smooth enough after the priming, as a guide coat, spray a very, very light coat of black aerosol over the bumper once the primer is dry. Use 400 paper, wet, to rub down the primer until the black paint has disappeared. You will see the black go speckly as the low points are highlighted. Keep the paper and bumper very wet, and be careful sanding higher areas in case you sand through the primer.

Next, thoroughly degrease and tack the panel again. Again, starting from the edges, apply either solid colour or base coat. After solid colour, sand any runs or imperfections with 2000 wet paper, and buff with G3 rubbing compound. If you wish, you can lightly scuff the whole thing and buff up again.

For base coat, de-nib any high spots, runs or dust specks with the 2000s, and lightly key the whole surface with the 2000s or a piece of red scotchbrite. Panel wipe and tack. Apply the lacquer (edges first!), de-nib any imperfections, very, very lightly scuff the panel with the 2000s or scotch, and use G3 with a buffer or by hand (depending on how confident you are about staying away from the higher moulded areas of the bumper and not buffing through!) until it's lovely and shiny!

Good luck, and post pictures!

[ChrisM]

What a fantastic post, Maria :thumbup: One for the FAQ, methinks...

You know, I may even be tempted to give my spare one a go after reading that...

[Maria]

Bumpers seem to be my speciality at the moment! I did Rich G's, and then our race car's (not to mention the rest of the flippin' thing!).

For those who haven't been in the events forum, a pic is here (http://maisie.accelerator.org/BrandsHatch/photos/photo7.html) (scuse the fly on the front wing! :o ).

[ChrisM]

We went to see the previous owner of TFC yesterday, and he commented how much better the bumpers look! :thumbup:

WBM is looking *very* nice also :cool: