Questions about high gloss enamel paint jobs.

[banzai]

Recently I've found myself in the uncomfortable position of having to play with Tamiya Enamels to get a durable glossy base coat of black for use with Alclad 2. I've not really used enamels before except for light panel lining so due to inexperience with the paint, I thought I'd throw my questions out there to you guys.

This is my own fault... Airbrushed on a good light and then wet coat and got a really pretty mirror gloss finish. Knowing how sticky this stuff is, I immediately put a clean plastic bucket over the pieces so no dust would spoil the paint job. Everything was fine but I couldn't resist... About 5 hours later I thought the surface should be dry enough for me to at least inspect the parts. I lifted the bucket off to examine the parts... GREAT GLOSS! Then I saw a very small hair and some small specks of dust in the air slowly drift and LAND ON THE PART! ARRRGH.

So now I have a tiny (less than 1mm) hair and 1-2 specks of dust embedded on the surface of the enamel. I was thinking I'd sand it off, but... Its enamel! Takes forever to dry. How should I proceed for a mirror like finish with just the gloss? (No clear, this is to be used as a base for Alclad, and it needs to bond directly to the black enamel.) So now, questions...

1) Should I wait for the enamel to fully cure and then wet sand with 2000, then work through the compounds to restore the shine? If so... Then how long do you think that should be? I've had enamel washes take about a month, sometimes 2 months to fully harden! Should I wait that long?

2) Or should I strip the paint and start over? Don't mind doing it, they aren't really big parts. If I do strip... Dot 3 brake fluid okay, or just soak in thinner?

3) Last question... Does anyone use some kind of drying cabinet with glass doors and stuff so that this kind of rubbish doesn't happen? Any recommendations? I understand this is kind of a niche thing but I'm sure you guys doing gloss finishes on cars have run in to this problem before.

Thanks in advance!

[banzai]

Heh nvm I stripped the paint with mineral spirits and laid down some new paint. I quite like the gloss you get from enamel but the dust man... Its like a dust magnet. Even with this new coat I couldn't avoid at least 1 or 2 small specks of dust. How do those guys doing car competitions do it?

I'm just going to wait to sand now. As long as possible, perhaps 2 weeks.

[banzai]

Okay the enamel is dry enough that it isn't going to be collecting any more dust, so I thought I'd post up a picture, and another question!

This is the enamel version.



Superrr shinnny I like. I'll probably start laying down the Alclad Chrome on this over the coming weekend.


And since I was already stripping the paint off the 2nd sword blade, I thought I'd do a version using Mr. Color, black undercoat and then shoot some Mr. Color clear over that. Want to see how the Alclad would react to 2 different kinds of paint. Here's where I ran in to some problems.


Lacquer version, WITH CLEAR.




Normally I use Future to seal my stuff but Ray suggested I try a hobby-centric clear instead. I decided to try it since I have a bottle of Mr. Color clear in my supply that I wanted to experiment with. Weird things are happening here with this 2nd sword blade. Using Mr. Color Clear (no. 46) over Gaia Ultimate black.

Shot 2 layers of black, one light mist, another heavier, about 20 mins in between coats. So far so good, satin like finish, very good coverage. Little bit of orange peel but I was experimenting so didn't bother. Didn't really pursue a high shine with the black, I figured the clear would take care of that.

Then I started with a layer of Mr. Color Clear. First thing I noticed, the stuff is VERY thick in the bottle, had to thin it quite a lot. First test on paper without thinning enough and it started to spiderweb. So thinned some more, and mist-coated. It looked a little flat but that's ok I thought, just a light initial coating. Waited another 30 mins or so.

Here's where the weirdness starts. I mixed up a thinner batch of Mr. Color Clear, and started laying on a very wet coat. It was going on smoothly, very nice and shiny without problems. After the coat was done I stopped to have a look... Thinner was drying yes, but still shiny. Great... Pegged the piece and stuck a plastic box over it to make sure no dust lands on it. I go back after another 30 mins to check and that happened... Its like all the thinner cleared away and evaporated all the clear as well. I can see the orange peel on the black but shouldn't the clear also gloss up the orange peel as well? Now it seems like the clear isn't doing anything. Its like I'm shooting air at it. Its like the clear evaporated away with the thinner!

then I tried another experiment, dripping some thinned clear on the piece of paper I used to test spray patterns when I was doing the black... It goes on fine, clear... Then the thinner starts to evaporate but it leaves... Nothing. Like there's no clear at all.

So I tried again, stripped paint, this time stripped off the primer too and did it on bare plastic (Plastic was polished first with compound.) SAME RESULT. I keep getting this satin finish instead of gloss. Can anyone help? Any advice on getting mirror shine coats with lacquer? Could it be my thinning ratio, psi... Or a bad batch of clear? I have no idea what's causing this.

Sorry I am long winded. Old farts tend to be long winded. Also apologize for the crappy photos... I'm still not sure how to use this camera phone that well. Color temperature is all messed up.

Oh sorry forgot to mention also... Using Mr. Color Self Levelling thinner. Light coat goes on at about 15-18 psi. Increased to about 20-22 psi for the wet coats.

[neofushion]

Well, Gaia Ultimate Black is more of a coverage paint than a gloss black paint and chances are, you thinned your clear coats a bit too much. If you are really really aiming for a gloss black finish, try sanding your pieces with higher grit sand paper (before and after priming). And if you can really really afford it, Alclad does carry their own gloss black as well.
There are a few vids on youtube to show how to achieve a glossy black finish as well.

www.youtube.com/watch?v=jOJvjCqXgqU

[banzai]

Cheers, checking out the video. Also going to do a test with unthinned clear. Its very suspicious to me that the clear isn't glossing up even when I just drip the stuff, so I want to see if I thin less and use a higher psi, if I'll get a better result. Worst case I'll strip, re-prime and drop some black enamel on it again. This is all for experimentation.

I did not know that about Gaia Ultimate black... Good to know!

[banzai]

Its the paint.

You were right about the Ultimate black... Its totally for base coverage. Stripped, re-primed, and while waiting for the primer to dry I tried going over some sprue with a proper gloss black. Shiny and wet, very sexy. I'm willing to bet you were right about over thinning the clear as well, although I seem to have trouble with that. Hard to see the consistency of milk when its transparent. Have to go with my guy feelings, or pull out the measuring cup and start writing down ratios. I've never really used clear before aside from Future... And that stuff I usually just spray without the need for thinner.

[neofushion]

You're welcome. Maybe try using a spoon to get the ratio you want. If you really really want to go for an ultimate glossy and super reflective alclad II finish: Plastic - 500 grit - 1000 grit then prime, wet sand - 2,000 grit, gloss black - clear. Wait for 48 hours (if you can) , apply compound from coarse, fine to finish then apply alclad.

There are other variationsto the above steps as well......

[banzai]

Yeah I went with the compound for the enamel version. It turned out beautifully though. I've been letting the enamel cure for about 2 days now but I'm going to leave it for at least a week before I give it any compound. A bit wary of how long it takes enamel to cure and harden completely. In the meantime though I'll be messing with lacquer for the other blade, probably playing with how to get the perfect mirror shine with Mr. Color/Gaia paint. Besides I have the rest of the model to paint. That should be plenty of time for the enamel to cure before I put down any alclad 2 on it. Well... If I can be patient enough!

I'll start taking pictures of the WIP soon. About time I contributed to the forum.

[Rayloke]

I guess the initial problem u had is due to too much thinning. Or, mebbe not.

Before stuff like leveling thinner, retarder, compound etc was introduced to modeling, enamel was the favorite paint for hi gloss, due to it slow drying time and as a result, its ability to level itself nicely. However, the long drying time at the same time create some problems too.

Many like to use lacquer for hi gloss now is mainly due to its relatively fast driying time; probably 3~5days to fully cure.

However, fast drying nature also means u might not have sufficient time before the solution become too thick to move n level itself. Hence, retarder's used.

Besides that, just like your case, the fast curing nature of lacquer makes it need to be thinned a lot more compared to enamel and acrylic for air brushing. As a result, with a higher ratio in thinner, it means the lacquer clear is much lesser in volume for the same amount of solution. To me, actually, is more of a good thing than a bad thing. The most important thing is, after cured, the layer of gloss is very thin, not possible to "cover" up any imperfection also means it will not cover up details on the model.with every layer being thin, the modeler has the flexibility to control the thickness; layer by layer.

Imagine if one layer of clear already cover up the orange peel on your black base, those who are painting on their cars, the key hole, wiper water dispenser etc, they would shed tears....

Normally when i was dealing with clear n hi gloss i tend to thin the solution slightly more dilute than it's used for wet coat.

I will do a few layer of mist coat, just a few minutes in between them (Can do a few parts together, start with part #1, #2 n continue until say, part #10, then go back to part #1 again.) I do this because the first few layer is mist coat which means chances of tear-ing is lesser, also give me a chance to warm up, to work with a more challenging/demanding control over-thinned solution.

Besides that, higher thinner ratio oso helps the layer of mist-coated clear attack onto the base color better. A stronger hold.

after a few layers of mist, normally by this time, the solution i have in the cup is starting to get thicker n suitable for some heavy wet coat.

Hope this helps


P/S: If u want, u can always bring the necessary stuff to icw, and we can on the spot experiment together.

[banzai]

That sounds like a good idea, Ray. I think I'll take you up on that next week Saturday.

In the meantime, 2nd blade has been re-primed. Found some small imperfections in the surface (I'm guessing it was all the paint stripping I did.) so I started brushing over with some Surfacer 500. I couldn't leave well enough alone though... I didn't like the design for the area near the hilt of the blade so I constructed something erm... "Different" with some epoxy. I'll post photos soon once the primer is dried and sanded down.

[Rayloke]

ah... next saturday i ll not be in.... QingMing festival......

[banzai]

Ish arright, in a fornight then. Time is not my enemy.

Edit - In the meantime I thought I'd share my recent results with some other parts that were prepared with black enamel and Alclad. These are much smaller parts, so the camera had to zoom in quite a bit. I do believe I'm getting the hang of it now though. Small part so I'm afraid the photo's a bit grainy.

Set against my other addiction, for a reflection reference.

Shinnnnnnyyy!


And this one set against a rather scruffy pair of metal tweezers for comparison. (Sorry I really should keep my tools cleaner. )



All in all I'm quite satisfied with how the Alclad went on... If well prepared I do believe the chrome will create a near flawless chrome surface that you could shave in! These pieces were not really polished before applying the Alclad, and I used about 15 drops of the stuff to get this. A few things I learned...

1) I don't think the manufacturers of Alclad were entirely accurate in their instructions. Well, I didn't follow them based on some advice I saw in a video online. Manufacturer advises 12-15 psi... I shot this at around 8.

2) Manufacturer doesn't mention exactly how light you have to be on the airbrush trigger either... You totally have to pull back the minimum amount when dropping paint on this. At such a low psi, the paint stream is totally invisible and you literally have to "feel" the paint going on the piece. At first you think nothing's happening, and then miraculously, you see the chrome start to appear! Tis most exciting, and I was damn nervous I was going to waste the stuff when I started shooting it.

3) Less is definitely more. I overdid it on one piece (I'll try to upload that tomorrow for your reference) when my finger was getting a little tired and I dropping ever so slightly too much paint on... You will immediately see it start to cloud up and be less reflective. 1 coat creates a very dark chrome. 2 coats I find, is ideal.

4) It will revel EVERY flaw in your paint job. Every single flaw, down to specks and uneven paint jobs that you can't even spot when you've got your gloss coat near perfect. Its a rather humbling experience but its also DAMN cool when you see the part start to chrome up like magic in front of your eyes! I'm grinning like an idiot now.

5) Cleaning up the AB after use is a pain. Don't ever let this stuff dry on your AB... It dries almost the same damn colour as your cup. Clean up immediately! IMMEDIATELY! And when painting, make sure you backflush the brush between coats, as I noticed the metal particles settle extremely fast. Backflush lightly before applying each coat. The particles are really fine too, it took at least 3 clean flushes before the AB was totally clear of the stuff.

I can't wait till the sword cures enough for me to try it on a polished surface now! Alclad is great stuff, When it cures I'm going to try and see how durable it is against some very light buffing. Then we'll compare those results - enamel prep vs lacquer prep. (Once I get my lacquer gloss paint-fu in order with Ray!)