BLACK !!!!

[paddy]

This is a problem i have had for years but never got to the bottom of...

I can spray any colour but Gloss Black.
I first ran in to trouble a couple of years ago trying to paint a RAF Hawk T1 ( which are all black in RAF service) The paint just seemed to fizz on the surface of the plastic and dry almost a crackle finish. I spent weeks messing around, stripping and re painting..I tried various aerosol cans and Tamiys paints. Nothing worked so i put it down to the plastic. some sort of impregnated release agent or something. some time later i tried to put a black finish on a Tamiya motorcycle and it was awful..not just orange peel, i mean a real reaction using Tamiya rattle cans on Tamiya plastic. I washed the parts, i got a perfect finish on an undercoat and allowed it to go off, the black went on well, a real wet gloss....but after an hour or so, back to a matt type rough finish. I have tried in Summer and winter, outside and indoors then suddenly i got a good finish using the same rattle can that didn't work on the bike..

Its a bit dusty but you can see the finish reflection is good and clear. This is straight from ther rattle can..


this is the hawk

And this is what i got today...incidentally this same can of paint went on perfectly as a high gloss undercoat for Alclad yesterday but it was on plastic that had been stripped of chrome so could be different type of plastic ?

Any thoughts ?

 

[jknaus]

Very weird. I couldnt even guess at the reason(s) for the inconsistent results. I might have a suggestion though to even the odds. My nemesis is gloss white. Cant spray it at all. But if I do a flat white base then a gloss white over coat it comes out well. Maybe the same for you? Flat black base then a gloss black top coat?
James

 

[paddy]

I use a dark grey primer /undercoat as that what the manufacturers suggest.I can get mirror finish with any other colour so i don't think its technique...

 

[Iron Mike]

That is very weird, Paddy. I love Tamiya's gloss black from the rattle can. I find that warming the can in hot tap water and applying very thin (mist) coats 20 minutes apart give me best results. Heating the can raises the air pressure and helps atomization. That orange peel you are getting is from too much paint at too low a pressure (my opinion). The first three coats I apply are kind of spotty, like I said it's a mist coat. The last two are pretty wet coats, shot from a distance of about 6 inches. If all else fails, wet sand the base coats and shoot again.

Smooth coats and a final polish are the keys. Best wishes! :drinks

 

[moon puppy]

I think James may have something there. do a flat base for the color then build up gloss coat clears to get the gloss.

I had the same problem with black, you can see that on the ol' Saber I've attempted a couple of times.

 

[Iron Mike]

You did not say what you are using for undercoat, Paddy. I've found the Tamiya Spray primers to provide the best results. B)

 

[paddy]

Thanks guys, it could be a pressure thing i suppose so warming the can is not a problem, i will try that.
I was using an auto motive undercoat for plastic. It did work on the car bonnet in the first picture however i suppose there is a possibility that i am not leaving the under coat long enough..and the undercoat is drying and contracting at a different rate to the top coat. Personally i think its a drying problem rather than a spraying problem as the wet coat always looks great, its an hour later it all goes pear shaped. Next job is black gloss so i will give the undercoat a lot longer to dry and then go with high pressure mist coats.
Cheers for your help

Mike, love that spun finish on the Airfilter, is that a kit finish or did you do that yourself ?

 

[matrixone]

I can't help with rattle can gloss black paint but if you were to airbrush it you might have better luck, what I do is thin the paint more than I usually do and spray wet on wet but you must be very careful to not over do it and get runs.
When I do what I described above I get a very glossy finish with no pebbling look to it.


Matrixone

 

[Iron Mike]

I'm thinking you're right about the primer and the paint fighting. I know Tamiya primer is expensive, but I have never had a failure when I've used it.

The air filter is an aftermarket turned aluminum piece, it's been so long since I built that one, I can't recall who made it.

 

[paddy]

Well its not good but its usable.Once the decals are on and i get a few clear coats on it i will be able to cut it back and get a finish.

I think the primer was the key :laugh: (get it ) the first coat went on and reacted badly but it seemed to seal in whatever is wrong and the second coat went on fine. I wonder if..as both this kit and the Hawk before are very old, 30years + if they use more release agent or if they somehow get release agent in the plastics make up ? You can definitly see the paint react on the surface of the plastic. I used Humbrol primer as i couldnt get Tamiya but it solved the problem anyway. Hope this helps someone
Cheers all

 

[moon puppy]

You do any sanding and polishing on this yet?

 

[paddy]

No Bob, not till i get a few clear coats on and its well hardened. Decals first.

 

[paddy]

Another epic fail on the Black then............. :laugh:

Room temp 72f can warmed in hot water....dry weather.

Gloss clear dried Matt but worse of all attacked the decals.

i give up with black :woohoo:

 

[moon puppy]

Man! what the world? what was the clear coat?

 

[paddy]

Yea,,,,,i just have to learn to avoid black

 

[matrixone]

Paddy,
Next time you need a gloss black finish try using either Testor's Model Master enamel or Xtracolor enamel paint. The key to getting a smooth pebble free paint job with these paints is to thin them more than usual and use medium to high P.S.I. and keep the airbrush moving while spraying or you might get runs in the paint. When spraying gloss black I do the opposite of what I usually do when airbrushing model paint and put the paint on thicker, with the slower drying time of the highly thinned gloss black the paint will even out nicely and not have a pebbly finish to it.
My experience with Xtracolor enamel paints is they tend to dry slower than most other paints do and need more drying time but do give me the smoothest finish.

Below is a Mercedes Benz German staff car built from the 1/72 scale Hasegawa kit and it was painted with Model Master gloss black with NO primer, in this pic the high gloss finish can be seen best on the fenders.

Matrixone

 

[paddy]

Thanks for that, it does seem to be a problem that others avoid so i need to stick at it

 

[Prop Duster]

Paddy :zen
[ol]
[li]don't give up,[/li]
[li]keep on trying,[/li]
[li]leave no stone un-turned,[/li]
[li]its darkest before the dawn,[/li]
[li]Rome wasn't built in a day,[/li]
[li]keep your nose the grind stone (ouch) [/li]

[/ol]

:laugh:
There that should take care of all the homily's and now you can restart your hunt for the elusive gloss black

Good Luck