Hi - first time painting a PC, although the actual paint has gone on a charm thanks to all the guides I've managed to find. My problem, is, however, with clear coat.

I bought a spray paint of Glossy Clear Coat, problem is, I can either put it on in a sensible manner (like normal spray painting), wherby it comes out with a speckled slightly lumpy finish, or so thick that it runs, takes about 3-4 days to not mark on touch and collects an interesting array of grit. It's suppost to be touch dry in 40 minutes, and thourighly dry 3-5 hours, which is about what I get with the irritatingly speckly method, so I can only conclude that is the way to spray it.

However, I'm having no such problems with a Flat Clear Coat by the same manufacturer (Plastikote), though I'm using them on different paints - (again Plastikote) Purple and Silver, both metallic (and the silver rubs off even when dry), and niether have their types properly explained. I've been putting flat on silver parts to prevent the finish just rubbing off - though I'm yet to try gloss on it because I've run out through having to redo clear coat on so many parts (either due to specklyness or large lumps where the paint has collected), so I may find that a new gloss clear coat solves the problem, then again, I may not

Now, my question(s) would be, if indeed a new spray of Gloss Clear Coat yields the same problem for me, what should I do? What would be the tried and tested method of spraying something that takes so long to become tacky? Any sort of indication about how long I should leave between resprays for a single layer would be handy (if I'm even suppost to be doing them), because I'm just going on guesswork (which could easily be wrong given my current results). Another option could be that I sand the lumpy/speckled with some P1000 finish until flat(ish), and return the gloss finish with some sort of polish - in which case, what sort of polish would I be looking at using? This is something I didn't get from the guides I saw, so apologies if I've missed some massive 'how to clearcoat' thread somewhere

Thanks in advance for any help, and I'm looking forward to finishing my project so I can finally put a few pics of it up on here, I've got practically everything else dealt with except for this clearcoat problem, and it's really holding my project up. (I've got A level exams comming up over the next 3 weeks, and I'd hoped to have practically finished by now )

http://guides.pcapex.com/pimprig_pai...ror_finish.php is Insomniac's guide for a mirror finish on clear coat.

A lot of factors determine how paint lays down and adheres, unfortunately with spray cans your limited to how you can control them. Weather has a lot to do with it. Don't paint when it's too hot, too cold or too humid. So does the spray tip on the can, with a lot of spray bombs if you find a tip that sprays well you can simply pull it out on put it on another can. Be sure and turn it upside down and clear it between coats.

Dry speckled paint that flakes off can be caused by several things. If conditions are good for painting it's probably the distance from the surface. Too far away and the paint drys a bit in mid air and doesn't lay down well. Flat paints are always more forgiving of poor technique than gloss paints.

I generally lay down a light coat and let it get tacky, then come back with a heavier coat. Sand with 400 or 600 grit every three coats or so. Clean the parts and use a tack cloth just before you spray. Always try to keep the same distance from the surface. Avoid overspray...get some distance between the parts you're painting or paint them one at a time. Hang the parts up so you can shoot horizontally, shooting down will not only put the paint can at a bad angle but gives the surface a big area to catch anything in the air that settles.

A garage is a good place to paint. Hose the floor down before you paint to reduce airborn dust. And most important, prep the surface well before painting. Insomniac's guides are the best place to start. Read the instructions on the paint can and adjust the distance from what your spraying slightly for best results. Test your technique on a box or something first.

Cheers for the responce - it is certainly not the meterological ideal here, around 27 degrees C and 65% humidity, so evidently not the ideal conditions. My only problem with what you said is, well, what IS too hot and too humid?

I tried swapping the head from flat to the clear, so I guess it wasnt that, plus, it doesnt flake off at all, it adhears just fine, it's just... not flat (if you meant the silver, it isnt speckled, the shine just rubs off onto your fingers). I attached an image (although fairly blurry) which shows up what I'm saying in the reflection, the left hand one is the 'lumpy' finish, and the right the much smoother finish, resulting from the super thick coat. (if you'll pardon the dust - these 2 pieces have been lying around waiting for me to solve this problem). I'm pretty sure it shouldnt be comming out like that.

WRT gloss being less forgiving, is that because it shows the innacuracy more? Because the flat is comming up physically flat, rather than lumpy and just looking flat.

I'm going to assume it's technique that's letting me down (since realistically, It's going to have some bearing if it is or isn't). I'll give hanging them up vertically a try, since so far I've been spraying them flat on the ground, though I'm skeptical that this stuff would be drying in the air if it takes 1/4 an hour to become slighty resemblent of becoming tacky. One lead is that it came out of the spray can in lumps (resemblant of an antistatic foam cleaner, and has always done this), regardless of range, shaking, weather, or cap, so maybe it was a duff spray can.

I'll give the following a try, then - wet sand what I've already got down flat (and removing any gloss finish) with 600 grit, hang it up, put a light layer of gloss on (which may not completely cover the whole surface if it's like the old can - if it was, the only way I'd have got complete coverage would be to totally goop it, and clearcoat would run everywhere), wait 30-40 minutes for it to tack up, put a thicker coat on, wait for that to tack, another later, tack, another layer, give it a few days to dry, sand again, and repeat a good few times. Sound like a plan?

If it still comes out of the can lumpy, I'll guess I'll stick with what feels like the right way of doing it, just overdo it a few layers (if such a thing exists ), sand it flat and return the gloss finish with the compounds etc suggested and a cloth or something, since I sure don't have a man portable buffer.

Cheers again for the responce, it certainly clarifies that this shouldn't be happening - any ideas on where to actually get the (or similar) compounds listed on Insomniac's guide in the UK is much appreciated, cause naturally I don't usually shop for this stuff and don't know where to look.

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Hi Goldfish,

The materials you need should be the following. Insomniac tends to have a pretty nice hookup saying he does this stuff professionally. This is the stuff I use:

Krylon/Car Paint (Any spray paint really, it's more a matter of preference)
Sandpaper (600 grit is good, but try to get some 1500 for the clear coat)
Hand glaze and rubbing compound (I get the 3M stuff, you can find it at autoparts dealers. I don't know the names in the UK, but similar stores to the US Autozone and Pep Boys).

Now I know you've been doing this, but this is a good reference for anyone else wondering too.

Spray the clear coat on, thicker layers than color coats. Generally clear coat is self-flattening (I prefer to do it laying down unless I'm in a paintbooth, which isn't often). Between every layer it's best to sand it down, the first clear coat I'd do 600 or 800 grit, the next layers I'd simply use 1500 and just be patient. Even when it feels like you couldn't sand anymore, just do it a little while longer to make sure you get rid of that orange peel, because if it shows up before glossing, you'll definitely see it once you gloss it.

After the final coat of clear (I usually do 2 or 3 coats), sand it down nice and smooth again with 1500 and now you're ready to gloss it. Use the rubbing compound, just follow the directions on the button, rub it in doing circles and continually put more pressure down. Once you start pushing down hard you'll begin to see some shining results. After 2 layers of rubbing compound, give it a little while to settle and then put on the hand glaze in the same fashion.

The rubbing compound and hand glaze are what really show your results, but it's the sanding job which is the most important. Take your time, be patient. That's the BEST advice. Painting is something you get better at with experience and patience. Once you start rushing the job, it'll show in the end.

This is BIG advice now. Make sure you are wet sanding that clear coat. You don't want to cause deep scratches. The wet sanding helps prevent nasty messes, some of which can be damaging to your paint job. Sure it can get a little messy itself, it makes the final result better.

I don't know if Insomniac will get to this thread, but I went through this with him back in the day and I've created some pretty slick looking paint jobs with his help, so pay attention to his advice, he's not called the Paint Pimp for nothin

Thanks, at least I know what kind of shop to look in, though granted it was always going to be either an auto-shop or a DIY emporium, heh.

For some reason I bought a heatsink lapping kit a while back, which came with a bunch of sandpapers, P400 to 1000 in steps of 200 (came in alot of handy during painting), and then some which I don't recognise - 40/25/20/15/10 micron (though the actual sheets are unlabelled and I've since lost the guide so I have no idea which paper is supposed to be which), though according to what I'm reading now, those gradings don't make sense, since that would range from around P375 to P1800, whereas they're all definately finer than the P1000, so I may experiment with some of those, since I have no more heatsinks to lap .

Anyway, cheers for the advice - though I'll still try spraying vertically to see how it goes - if it starts dripping down and sagging I'll go back to flat. Also, I'll go ahunting for rubbing compounds and hand glaze tomorrow or the day after, since that sounds like what I'm going to need regardless of how dodgy my new spangly can of clear coat ends up being. Infact - I just tested it, comes out ALOT better than the old one - this time it does actually get flat with a realistically thick coat, damn you plastikote and your faulty spraypaints! *shakes fist*

Looks like someone will be clear coating things tomorrow, hehe. Thanks for all the advice and I'll be getting back to you with the results (Unless they're god awful). in the mean time, I have some interesting looking lumps to get out of this clear coat. Cheers again, both of you.

Oh, and you can create some very interesting scratches with a dry sheet of P80...

No prob. Yea you'll notice you'll see some things which will help make your next paint job better. Practice makes perfect in this portion of modding for sure. Also, clear coat tends to sand flat easier than color coats so you'll notice those bumps coming out.

As long as your color coats were flat and you didn't have too many drips or any drips at all, it doesn't really matter if there's drips in the clear coat, because if you get that flat to where you can't feel em, I'll doubt you'll see em once it's all polished. Have fun, I can't wait to see your results.

I work at a custom body and paint shop, www.rusttorods.com, shamless plug. Humidity definately is a factor, you want to have at least 25% to 35% humidity, if you dont have a hydrometer than a good bet is in a garage with an exhaust fan in the window. I use Dupont automotive with a Sata jet 90 HVLP gun, but if you dont have axcess to these, you cant to a paint supply store and they can put professional grade paint in a spray can for you and also tell you the exact specs for spraying the specific metal your using. Also for a high gloss finish youll want to wet sand with 1800 grit and hand buff with a meguirs scratch remover to a high finish. If you dont trust me check our web site, if you have more specific questions just ask, or ask the paint match person at your local auto paint supplier.

Low humidity isnt a problem here - what may be though is high humidty, it ranged from 96% (3 pm) to 51% (10 pm) around this area today. Lower limits are all well and good, but what I need are upper limits, if there even are any. Ideally I want what is possible, not just what is best.

And certainly, if I wasn't painting a case I picked up for 13 pounds (with vile PSU) I'd consider actually geting some profesional grade equipment and paints to paint it with, but all this stuff is strictly amature, so I'm quite happy with 6 pound-a-go spray paints and my fairly fine-ish unmarked sand paper - I don't intend to get the perfect pristine finish, just one that's nicer to look at than an empty wallet.

okay then I would go with an automotive paint supply store with the pro paint in a spray can, its definately better than plastikote and maybe a buck(pound) or two more a can but you can really tell the difference.

Goldfish,


about to go through the same as you.

was wondering if you had any luck.

currently using plastikote.

was wondering what you found (in uk) to polish the case up.

I'm afraid I never had any real luck with the platikote gloss clear coat stuff (the flat seemed to work fine, but always came out slightly yellowing (and flat, obviously)) - in the end I didn't use it at all. You could have better luck, if you still have the bit you cut out for your window (which I'm gussing you'll have done), have a test spray on that, see if you can fathom how it's suppost to work, heh, for all I know I was doing something retarded with it. I did eventually get the impression it might be the paint (colour) I was using, it seemed to be pretty much ok on a few random other bits of stuff I tested on, though obviously I didn't dwell on the bits that weren't part of my PC, heh.

Also, I did find the rubbing compounds etc at a small time local auto-thing store, sort of place boy racers would order stuff in from, heh, seats, rims, weird ass engine parts that I have no idea what are, that sort of thing.There's about 3 different shops like that near where I am, so I'm guessing they'll be pretty common in towns around the country, though I'm not sure if they generally have them, the first one I went to had them (which was the largest of the local ones).

Good luck to you, hope you have better luck than me (at least wrt the clear coat)

ok thx goldfish