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Hi guys. Have recently gotten interested in panel beating and have acquired an unused wheel arch panel from a mates garage. It had some nasty dents and scratches, I was originally oging to just remove dents and scratches, but seeing that I gotta spray gun etc I thought I might try my hand at a total respray. I removed most dents, bogged another dent that wouldnt go straight. Then I sompletely sanded the entire panel and primes it. After priming, I sanded one last time with 1200 grit wet n dry. I did a few gloss black coats (all the spraying was spray cans btw) then a few clear coats. I am happy how new the panel looks, BUT I am not happy with the surface. The surface is not like your average cars glass smooth surface, it is the surface of dried spray paint (you know what I mean). What I want to know is, how do you achieve that extremely smooth surface? should I sand the top coat one final time then degrease it all to remove the dust? or is it just the fact that proper sprayers use that gun where the paint is charged positively and the panel is negative or whatever that spraying setup is called? Thx guys, appreciate any answers.

Im assuming ur cans were acrylic? That being the case, yes, you need to cut back top coat with 600 to start, then 1200 and maybe 3000 to finish before using a cutting compound and polish. It'll look worse before it gets better. Where r u located?

If you say you put clear coat on last - I wouldn't wait until it is completely dry (Normally 1-2 weeks). I would fine sand the clear coat after 2-3 days when it is solid, but not completely dry - This makes it easier for both sanding and buffing/polishing the clear back to glass.

Ok, I will be adding ONE more coat right now, then once it has dried, will sand all the way to a real high grit (wwhatever the highest is in my garage, I think 1500 or 2000). I am located in Hornsby, Sydney. Thanks for your replies, and I have compounds and polishes, so will sand it all down, de grease again then polish it all up. thanks alot guys.

One other questions, where can I acquire proper spray gun paints, like the primer, clear top coat, and then specific colours? I know there a dulux type shop near my house, but would they have auto paints for spray guns? thanks alot guys.

Make sure you buy auto paints! I'm not sure in your location, but autobarn is a popular place in Brisbane to buy mixed and matched paints.

When sanding down, make sure you don't sand TOO much. Also be prepared to get scared when you see how ugly your clear coat will be at sanding. Remember, the hazy white colour will come out in the next phase: buffing.

Last clear coat done, waiting to sand, unfortunately/ fortunately the sun it RIGHT on my panel, so its drying fast... thanks for the rpely, autobarn is about 15 minutes from my house, autoone and repco are about 5 minutes away, so im in a good area, will check autobarn when I have a chance :D and I get what you mean about the white haze, I have seen it before when my mate thought it was a good idea to sand pat of his boot because he thought it would fix the scratch............................... Thanks alot, will come back on maybe tmorro or the next day and say how I went :D thanks for the help fellas.

So pretty much I sanded it very lightly then cleaned with water, then compounded it with meguiars, then used polish. It looks good, but not 'real'. It looks more like a plastic wheel arch with a bit of gloss that plastic bumpers etc have, it does not look like that glass surface, black miror like surface :( I think maybe I need to be using a spray gun right?

Nah you don't need a spray gun man... Make sure you don't sand it too early. I would wait AT LEAST 24 hours, but like troy said, no more than 3 days (Begins to harden too much).

Also again, agree with what Troy said, you need to sand it back enough to get rid of those bumpy orange peel parts (The parts which are a tad higher than the rest of the clear).

That said though - You don't want to sand PAST that flat bit, because all sanding after that, is sanding into good clear.

Make sure you use a good buffer as well. You can't really hand polish that hazy look out well, you do need a good quality buffer and also, just as importantly, a good buffing pad.

Edit: I've done great clears with the good quality can stuff. I have a air gun as well, but wouldn't use it unless its something good sized (IE: Bumper +). There are good quality cans these days are pretty awesome.

Edited by wilorichie

Ok, that is what I did wrong. I sanded it like one hour after applying the last clear coat :( I will give it another shot. I do have a buffer, its a rockwell one from supercheap, works well, and I got a foam cutting pad. I dont think what I used was degreaser, but I do not know, its just what I got when I needed to get a layer of wax I applied to my car a few months back, it is called grease and wax remover, got it from repco.

Thanks alot guys, All the info is REALLY useful, so thanks alot.

sorry to hijack, but if using a gun, do you still need to sand the paintwork after the clear is applied? it just seems weird to go to so much trouble getting a perfect prep/spray job done, only to sand it back again once finished??

Edited by adamskill

Ok, so here's wat i've worked out so far. (excuse the obvious being pointed out, a mate of mine yesterday was sanding back a layer of paint from a front bar with the dry 60 grit sandpaper for timber) so i'll try be thorough.

As much as the damage "doesnt look too bad" with some shiny paint left intact in places, be brutal. Its gomna be fixed, so dont try and preserve anything. Always easier to do a bigger area than blend a repair.

I usually start with 220 grit (wet n dry for all this, paper or sander in one hand, bucket and sponge in the other) for taking back paint, but for removing old bog or fibreglass, might go down as far as 80.

Take off a few layers of paint and see what you're up against, bog always binds better to bare metal too.

You can obviously mix bog correctly, fill and shape, its the sort of thing you'll wanna let dry overnight to be sure its set, everything takes time.

Fill holes with "metal fill" its a cross between fibreglass and bog. Harder to sand than bog, but so much stronger.

Once overfilled (always over compensate the shape you want) start sanding back with either 220 or 600, depending on the area being done, 220 for something the sander is going to have a lot of movement over, 600 for finer areas and corners.

Hopefully by now you have the shape you want, if not, repeat bog step above, only using 600-800 this time, being more particular to fine ripples or dips.

"Spray Putty" in a can is a godsend. Its a spray on, fine layer bog ideal for getting rid of stone chips or scratches. Allow about 5 hours for a generous coat of this crap to dry though, it can also undo a lot of hard work by "peeling" the whole layer off if u sand with too much pressure before set overnight.

Sand with 800 now, focusing on imperfections, air bubbles (you see these when the job is dry, so its important at this stage to keep washing down with water n sponge, and rag drying) and overall job finish. Ask yourself, is this ready for topcoat? By now it'll be looking pretty alright, but mulitcoloured. Base coat prime 2-3 coats now, and allow a few hours to dry.

Now that its all 1 colour, you're probably cursing at those spots you didnt feel or see earlier, so again make friends with the spray putty and sander. Get it right at this stage, or no amoutt of polish at the end will get you out of the shit you end up with.

Once happy, give a final coat in surface primer, allow to dry for a couple of hours, and give a light sand back with 1200 to smooth over. You're practically polishing it here, not removing paint, so focus on removing any scratches, and dont stay on the one spot too long. Wash with water and a sponge, allow to air dry, then use "prepwash" or similar to wash off remaining paint dust.

Happy with how it looked buffing with that shiny liquid? No dents, good shape? Buff dry, and check for pinprick holes from air bubbles.

Topcoat time.

Any acrylic in a can will do, but autobarn can mix any auto colour to a paint code, usually no more than 30 bucks.

3 even coats, allow a few hours to dry, then 1200 it smooth, wash with sponge and water, prepwash and allow to dry.

Clear coat is this process repeated, but dont touch with paper once sprayed.

48-72 hours is time required to dry for clear to be cut back.

Start with 600 to remove orange peel look, then 1200 to remove the 600's scratches, then 3000 to remove the 1200's scratches.

Finally buff with a cutting compound, and finish with a polish/wax.

This was originally a PM, but good info to share here. Feel free to add anything i left out or go into more detail. Hope this helps. :)

so, im doing bit of touchup (acrylic in spray can) on the rear bar, basically the colour used ended up being bit darker than car colour , havent applied any clear as yet

what can i do to make it lighter other than starting all over again?

My only thought, is that, this seems like alot, I mean ALOT of work to get a single panel finished, so is this the same sort of process used for an entire car respray? because if it is, I would never have thought they did all this :(

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