Plastics and metals respraying

[spetom]

Hypothetical noob question:

Lets say I take a bike where the fairings as well as metal tank are all in red colour, there are stickers + decals and its all been lacquered. The plastics on some of the fairings are damaged and cracked. The wheels are in an Red colour also.

Let's I would like to do the following:

-Repair the plastics
-Paint the fairings, the wheels and the tank all white

Question is how do I strip the plastics and the metals?

Would I have to undercoat the metal parts with zinc before repainting?

[c_dug]

I may be wrong but I believe I have read on hear before that if there is a layer of paint there is no need to use any sort of primer.

By a layer I mean after sanding, not just paint over the original paint.

There are a few experienced bodywork/painting people on the forums, usually with conflicting opinions, I'm sure they will be along for an argument in a little while
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[Shaft]

OK, I'll bite

For stripping, you've got three options.

1/ Sanding
2/ Paint stripper
3/ Media blasting

Starting in reverse order, media blasting (sand, plastic, glass, walnut etc) is a specialist task, so you'll have to pay someone to do it, unless you want to buy all the kit (not very cost effective).

It's also a bit harsh and, if you use the wrong media or get a bit heavy handed with it, you'll knacker everything beyond repair.

I'm not a big fan of chemical stripping, unless you absolutely have to get back to the base material; it's messy and you have to make sure you get every last trace off, otherwise your new paint will be ruined.

Also, some plastics won't tolerate it, so test a part of the panel that can't be seen and if it starts melting, wash it off quick!

Rather annoyingly, not every piece of plastic is always the same type, so you might test it on a side panel and have no problems, then you slap it on your fairing and get into a great, globby (and expensive) mess.

So, it's rubbing down, either by hand or machine; if you're doing it by hand, invest in a decent rubbing block, or go down the machine route and get yourself a random orbit sander (about 20 quid-ish from Screwfix/Machine Mart) and save yourself a lot of time, although you'll still have to resort to elbow grease, if you've got nadgery little corners to get into.

Wheels I would get blasted, probably by the bloke that was going to powder coat them.

As for the primer question, in your example you've chosen red covered by white; red is notoriously difficult to cover and white is notoriously bad at covering, especially if you're using aerosols, so I would use a light grey or yellow primer, to kill the red and provide a better base for the white.

In any case, if you get down to bare metal, then you should prime that area and, if you end up with a patchwork of colours, you might be as well to prime it anyway, just to give you an even base colour.

There you are, that's my tuppence

(puts on nomex suit and waits to be flamed)
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[owl10]

I was under the impression that white on red is quite a difficult colour change, as the red can leach through into the white?

Maybe wrong, though one thing i do know is that the finsh quality of the new paint will be directly dependant on the quality of the prep work.
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[spetom]

Thanks Shaft.

With the metal tank I reckon its less of a problem, I've resprayed metal before, manually stripped the paint with fine emery + water, I'm thinking chemical is probably a better way to get to the base as there is always a chance you slightly sand down the metal itself (but I've never tried this). Then primer, maybe zinc primer then paint.

It's the plastics I really have no idea about.

Likewise await flame.

[gray84]

treat the plastics the same way you paint the metal...
no need to strip all the old paint off you just need to flat it all down so its smooth and got no shine.. then prime up to give yourself a nice even solid base . paint and lacquer..
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Road bike - 2002 YAMAHA R6(SOLD) 2008 YAMAHA R1(SOLD) 2007 APRILIA SXV 550(SOLD) 2007 SUZUKI GSXR 600
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[ZRX61]

[tutton]

Let the paint flame wars commence!
if i were spraying a red onto a white panel, i'd tint my wet on wet primer red, and tint it white for white or just use grey for white.
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Past: '05 Peugeot XPS '99 Aprillia RS125 '94 FZR600R
Current: '02 ZX636 A1P '51 CCM R30

[stirlinggaz]

hi all,
been a while since i posted/replied to anything, but i've done a fair bit of re-spraying & offer my opinions/experiences.
there are are a couple of pros on here & can give you some good advice. (such as ZRX61-who may suggest some products which are hard to source in the UK, but well worth listening to & TUTTON, whos also good for advice etc)
anyhow, assuming your not a pro & dont have access to the tools & products that are available to them, heres what i do, with reasonable results.
wet & dry everything. (theres a few on-line guides available, which i have found invaluable)
get good products & get as many different grades as possible of wet & dry.
wheels - give to powder coaters & they will shot/media blast them & powdercoat them in your chosen colour. far easiest option & sometimes cheaper than DIY (30 quid a wheel?), & pretty fast turnaround.
though i have used nitromors on wheels & painted them pretty successfully myself, but its all in the prepping & it can be pretty messy & time consuming but once painted & clearcoated a few times, it seems to be fairly tough.
plastics - wet & dry, grey primer, basecoat (colour) & then lacquer. & polish, im presuming you have a compressor & gun?
if not, well worth getting a small home compressor & half decent guns.
i use a small compressor, which is perfectly adequate for fairings etc, though the bigger the compressor the better, obviously,lol
i use a cheap gun, with slightly bigger nozzle for filler primers, hvlp gravity fed gun for tanks,bigger panels etc. & a small gravity fed gun for touch ups etc.
never had any issues with old colour leeching through.................though sealer has been suggested to me before.....
i have just re-sprayed some plastics white, which were previously red (mito panels) & i just rubbed them as flat as possible, using decent wet & dry, then gave them a good few coats of filler primer (beige?)& then painted as normal (& i've done this a few times) clearcoated a few times, added decals, then clearcoated again.
guess im not saying anything thats not been said before, so i'll stop rambling on,lol
post the pics? before, during & after?
im always interested to see other peoples attempts at re-spraying.
good luck,
cheers,
GAZ

[tutton]

Dont do custom work like zx does but work in a bodyshop as a painter. some pics below all are pre-polishing straight out of booth.

First pic being a repair done to bumper then blended out and laquered.

Second pic being my bike fairings after i crashed and repaired them, front nosecone in ford frozen white same with sides and tail

Third pic being rear hugger, same colour on front hugger, and tank, Custom mixed colour.
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Past: '05 Peugeot XPS '99 Aprillia RS125 '94 FZR600R
Current: '02 ZX636 A1P '51 CCM R30

[stirlinggaz]

looking good.......................
particularly like the mettalic paint.
my results are not quite as good/professional looking, but for jobs done in my spare room look ok,lol
(new pc but will upload a few before/during/after pics of my most recent attempts, once i've set it up properly)
coincidently, im just about to do my r30 & another mito, (both needing damage repair & full re-sprays, a so i'll do a "start to finish" post if anyones interested.
cheers,
GAZ