Spraypainting

[PUR157]

Hi guys,
I recently grabbed a cheapy 2nd hand spoiler from Yahoo Japan that I need to paint match to my car
Just looking for some advice on prep work...

What grade sandpaper do I use to strip back the current paint? (it's the OEM plastic ducktail spoiler for NAs)
and I assume I need to prime it before I go coating it with the body colour?

edit: just spent some time going thru "Patchy's Labour of Love"
is 800 grit the go? Just don't want to go making unnecessary gouges from sheer enthusiasm...
and what was that primer that you used that didn't end up reacting with the old paint, STM?

[StanTheMan]

currently I'm using

240 before filler primer

400- 600 before paint.

1000 between clear coats.

spoiler......I can't recall.....but it did eventually bubble in one little spot which makes me think that was a reaction.
We did use a clear flexible primer......

[Mr Morlock]

I would not disagree with Stan however there are always diy books in libraries with lots of accessible info about painting. Auto paint suppliers can also give advice. I would assume that you would be able to repaint the spoiler with matched spray cans and finish with clear coat.

[bensale]

Does the na8 white have a clear? I know the na6 doesn't.

I sprayed my windscreen frame, basically did what stan did but went to an 800 for the very last sand before painting. Multiple light coats are much better than one heavy one And yes, I have one little spot where the paint reacted too. Sanded it back and re painted but it came back... Not noticable unless you point it out though.

[Mr Morlock]

I would guess all the metallics use a clear coat but the solid colours such as white do not. There was a post on polish with a listing of paints and whether clear was used. If one buys a matched colour it will probably advise if clear is required.

[PUR157]

Thanks for the replies guys,
I've had a look at some panelbeating books at the library but just wanted some more current information

Just 'coz I'm a little OCD and alot thick...

What you're saying is...
240grit for getting rid of old paint
prime w/ flexy primer
400-600 to smooth out primer
paint

iirc from the TR3 polish thread that my white, (chaste white) isn't clear coated

[StanTheMan]

Correct my NA6 wasn't clear coated either But parts of it now are.
also the 240 grid is rough enough not follow the contour & hide bumps. On Larger panels I've been using 180 grid with a machine to remove my contaminated paint from the panels. Then go over it with 240 by hand. but also sand as many different directions as possible.

I guess between coats of paint I'd use about 1000 grid.

for a spoiler......I'm about to do mine......not sure if id go to that much trouble though. But on the other hand.....all my paint needs to come off.....every little bit of it. so 80 might be on the cards for the front lip.

[PUR157]

I see... thanks again!

Just looking at the sikaflex website now... any recommendations which one I need?
Would the multi-purpose one be enough?

I'll ask someone at Bunnings too but just in case I get a monkey...

[Mr Morlock]

Bunnings are a poor choice for info on automotive painting and prepping. In Melb there are quite a few auto paint suppliers ( assume Sydney w/be the same- often small businesses and these guys are helpful.

[fung9420]

depends on any paints or coats on the spoiler.
using a spray can? or spray gun with air compressor?

I had done 3cars recently. the 4th will be the mx5 NA just bought a month ago.
For arcrylic paint:
240 Dry sand a little
400 Wet sand
Primer -- Just enough will be fine. Do not put too thick coat.
400 Wet send again
wax or grase remover to clean the surface
spray a very thin coat on the surface
let it half dry
if u dont have very good tools
u better spray a few coat to build a very wet/smooth coat
wait to half dry between each coat

let it dry a day or 2 (depends on the weather)
remove the dust
put clear coat
very thin coats
also half dry between coats

after 2 or 3 coats let it dry an hour or 2.

i would do 3 to 6 coats for the job

let it completely dry a day or 2
sand the surface with 1200 -> 1500 -> 2000
Make sure u have completely smooth out the clear coat to receive best result

At last, Polish 2 or 3 times....

[PUR157]

Good point Mr M... I'll have a see what more I can dig up

Yikes...
Very in depth there Fung, thanks for that
Are you in the spraypainting trade??

I'm doing it just by cans, as I only really do these things as a hobby... I'm thinking the paint on there now is just the original paint
(Silver for NA MX5s... apparently came with clearcoat)

Should I be doing a clearcoat?

Also forgot to ask... how's the progress on (soon to be) Dijon STM?

[StanTheMan]

Good point Mr M... I'll have a see what more I can dig up

Yikes...
Very in depth there Fung, thanks for that
Are you in the spraypainting trade??

I'm doing it just by cans, as I only really do these things as a hobby... I'm thinking the paint on there now is just the original paint
(Silver for NA MX5s... apparently came with clearcoat)

Should I be doing a clearcoat?

Also forgot to ask... how's the progress on (soon to be) Dijon STM?

progress has stopped due to some other things......but I should be back into it in a week or so.

[green_comet]

I painted a spoiler only a few days ago, its a Mazdaspeed front lip for a BA Astina. I got it from overseas for my uncle, and painted it sparkle green to match his car. He is coming over in a couple hours to help fit it up.

This is it here, still needs to be 2000 wet sanded, and polished, but ill leave that for another day.







All I can say is make sure you keep it clean, use prepsol as much as you can.. one little dirty spot will show in the finished product.
I would also do a few clear coats over the top.

[RawSouth]

wow, thats a great job!

[green_comet]

Just finished fitting it up, and took a few pix...