Plastic Model Kit Thread.

I have an iwata. It's a great airbrush and very easy to use. I can't paint with a brush worth a damn when it comes to large areas. I learn something new every day from those forums and have a long ways to go. I tend to do as much as I can and make things as real as possible. Although am not modeling right now, I am getting as much info/pics on my Dad's ship when he was in the Navy and will give it to him. Modeling is very addictive!

 

I'm loving it so far, I have quite a lot to learn-Most will be through first hand experience and YouTube though. My dad had a '69 Road Runner that was orange when he went to high school, this one of the main reasons why I picked this model.

I've been wondering if I can somehow sand the paint even though it has two coats of clearcoat just to give it that smoothness that I'm looking for.

I honestly don't know the difference between wet sanding and just sanding the body while it's dry. Will it ruin the paint by wet sanding?

 

I've always used this with great results...

$30 Micro-Mesh 9 Sanding Sheet Introductory Woodworkers Kit with a 2" by 3" Foam Sanding Block

http://www.amazon.com/MICRO-MESH-SANDING-SHEETS-INTRODUCTORY/dp/B000H6HIK2

 

That's just what I need! Thanks for the link.

 

No problem. It's a little scary the first time because you will scuff the hell out of the clear coat. But then as you work your way through the grits it gets glossier and glossier and at the last grit it's nice and smooth. I like to finish with a little plastic polish or turtle wax.

 

Should I wet sand the clear coat, or do you think that will ruin it? I also noticed other builders use polish, pretty neat idea.

 

I've never wet sanded. I've always used the micro mesh polishing kit. You can wet sand with a fine grit and polish it out but you will need at least 6 or so coats of clear. The kit is pretty fool proof. Wet sanding and polishing you need to be very careful on raised areas as you can take off too much clear or even the base coat if you're not careful.

 

Just finished clear coat #5, here it is right after I put the last coat on. 3 coats of grey primer, 3 coats of Hemi Orange.. You can see the bumps in the picture right now; hopefully that will go away after I sand it in a day or two. I put on two extra coats of clear just for that reason^^

 

Are you warming up your spray cans before you use them? I will usually get a bowl of very warm, almost hot water and put the spray can in it for a couple minutes. That warms the paint up and helps it atomize better. Helps to eliminate the bumps.

I typically use an airbrush for painting my models, but the process is the same for the spray can. I primarily use Testors enamels, but if you use lacquers you don't have to be as careful about time between coats because it dries so fast.

The first step is a good primer coat. I typically use white on cars because it helps the colors "pop". Gray primers tend to dull the color down a little. If the body needs some more prepwork, I usually let that dry a day or two and then sand everything down with some 600 grit wet/dry sandpaper. Usually I'll wet sand this. The key to a good paint job is a good primer coat. Once I get a nice smooth primer finish on it, I start with the color coats. I either start putting these down within 15-20 of spraying the primer, or wait at least a day. If you spray in between those times, you run the risk of the solvents from the coat you are spraying eating through part of the primer coat into the softer, uncured paint underneath and "lifting" the paint up. You end up with something that looks like dinosaur hide.

With color coats, I usually start with a very, very light mist coat, which helps keep the paint from building up in creases and corners, and pulling away from edges. After that I usually wait 10-15 minutes and then put on another light coat. After that it is just keep repeating the light coat, wait 10-15 minute process until you are happy with the finish. The very last coat I usually will make a "wet" coat. With an airbrush, this usually means a touch more thinner in the paint and spray right up to the point the paint will want to run. It's tricky to do and it just takes practice. One of the other important things to remember is to try and get those hard to reach areas first, like head/taillight recesses, the inside of scoops, undersides of fenderwells, etc. The reason why is the surrounding areas will get a little more paint than normal because you are trying to get into all the nooks and crannys. If you already have paint around those areas, you'll end up with runs.

After that, I try and place the body somewhere I don't have to worry about dust or bumping into it and let it sit for a few days. It's hard to do, especially if you have stuff masked off, but don't touch it! The surface will be dry to the touch in under a day, but underneath the surface is still wet, and you can still leave fingerprints in the finish. If you are going to put a clear coat on it, I would recommend waiting at least a week, especially if you have to sand out any dust particles that may have landed on the surface.

I build mostly race cars, so I usually don't mess with clear coats until after I put the decals on, and even then I'm not looking for that "miles deep" shine. If you saw my Hudson Hornet earlier in this thread, it was painted using this method and there is no clear coat and has not been polished or sanded after the last color coat went on.

I know this was a little long, and a little late for the model you're working on now, but hopefully it will help you down the road.

 

My suggestion would be to remove it entirely and start over...I don't think that sanding will even that out... Thats a pretty big orange peel effect going on there and even if the clear was sanded smooth the blemishes will be visible... Oven cleaner and brake fluid works great as a paint remover (for enamels and laquers) - just gotta be careful. Once everything is removed, I would suggest a healthy dose of practice before spraying - that way, you know the correct distance from the model, speed, etc. For me spray cans are very troublesome, thats one reason why I got the airbrush. Once that is done, I would suggest waiting several hours between primer coats, but then a day or so before you add the paint. That way, it can completely cure. Same goes for the clear coats...

 

Yeah, you may want to start over on this project. It's happened to me before and I know it sucks. Everyone said just about what I was going to say but I can add a few more tips. Like already stated heating the paint can up helps a lot, but also try not too paint when it's too humid or it will be orange peel city. I will let you in on a little modeling world secret that works wonders. Get yourself a cheap food dehydrator. It works great to cure the paint quickly and "bake" in the finish. My general rule of thumb when using it was: 3 LIGHT COATS of primer, 3 coats of color which doesn't include the mist coat and they about 5 coats of clear (sounds like a lot but 2-3 of those will be lost when sanding/polishing. I would allow 24 hours in the dehydrator between the primer coats and base coats and then a few days after the clear. Hope this helps a little. Good luck!

 

What he said...

Also, make sure that your primer is smooth because any blemishes WILL show in the paint. Primer isn't necessary - never use it except on PE or resin... That said, Tamiya white primer is one of the best and really only necessary if you are painting bright colors like the orange or yellow (yellow is a bitch!)... Feel your pain!

 

Thanks for the advice guys. I'm going to strip the model and wait a day in-between the primer coat and the color coat. I'll also wait week before I put on the clear coat. I'll also make sure to let the spray cans sit in the warm/hot water before doing my coats this time. Sorry if I'm not clear with what I've written below, there is just a lot going through my head right now.


I just want to be clear on this subject: If the primer seems to look somewhat rough after waiting a day for it to dry, should I wet sand it to make it smooth and continue with the color coat? Same question with the color coat if that too comes out rough after waiting for it to dry for a week.. Should I wet sand that too before applying the clear coat?

I just want to be extra sure because I did notice the paint became progressively worse with the orange peel look after going from primer -> color coat -> clear coat. It almost seemed like a snowball effect..

 

No problem - I wish that I had help when I started up! If the primer is rough, then it needs to be sanded - either wet or dry (I have never wet sanded my models) - with a very, very fine grit. That's one thing the primer is for - not only to show what, if any, needs fixing (as in pinholes, seams, etc). Even though I don't use primer (with the exceptions I listed earlier), on occasion I will use the Tamiya white in place of paint if I am painting something like a rudder or panels or the like - its white and looks good...but I have over done it on occasion and had to sand (1000 grit and up) and redo. Like I said, I HATE using spray cans but still do anyway! I am at work now, so I can't look at the stuff I have.

Once you are comfortable with using the spray can for your color coat and the primer is smooth, you shouldn't need to sand the paint at all. However, if you have to, the do it very lightly or you may find the plastic showing!

I can't stress the importance of letting it cure before moving on. A great, and I mean great clear coat for shine is Future - you know the stuff used on floors...its acrylic (make sure the bottle says so) and is self leveling, meaning you can brush it on - just let it dry and don't touch it (or any paint) until then...I use it before decaling (because it is a gloss and therefore smooth, not "grainy" like flats are) and after if I am looking for a gloss coat. Otherwise, I use Humbrol's Satin Cote for most of my stuff (has to be sprayed on by airbrush).

 

One of the things that helps out with wet sanding is that as long as you keep rewetting the paper, it carries away the dust particles, which can actually be bigger than the grit of some of the finer papers. In the car world, some people will actually wet sand between every coat. That's a little much for me, I just sand when I need to. Be very careful around edges though! The paint is always thinner here and it is very easy to burn through it. You'll notice this when you go to sand your first primer coat.

 

I have 180 -> 600 grit right now, I'm going to see if the local auto shop has 1,000 and above. When I wet sand between primer -> color -> clear, is it a rule of thumb to wet sand the body in order of 1,000 grit -> 1,500 grit -> 3,000 grit, or do I just use 1,000 grit and move on?

I ask because I watched a video of some professional using three different pieces of sand paper, which I assume made the surface even more smooth instead of using just one piece of sand paper.

(Last question for the day I promise)

 

Damn, y'all car people are crazy! Sounds almost as big a pain as doing a natural metal finish!

 

Any autoparts store should carry the paper - I got some from autozone. I personally just use 1,000 (or maybe 1200 - whatever I can get my hands on) but then again I am not a car builder. The idea is for a smooth finish. Now when I am doing a natural metal finish, I will go progressively finer, but that is on the plastic itself and not primer/paint...thats because every little blemish shows when doing this style!

Still interested in the Panther?

 

Whoops. Sorry, I forgot to reply. Just sent you a message.

 

Thoroughly removed all the paint from before with some brake fluid.(That stuff works great!) Washed the body with some dish soap and hit it with a tack cloth and managed to get three nice coats of primer. It looks a lot better than before, heating up the spray can really does the trick. Now to wait until tomorrow.