SciFi Model Action

Modelers Questions Board => Modelers Questions Board => Topic started by: digitani on October 27, 2017, 07:53:02 pm

Title: Oh no! My clear coat has fibers in it!
Post by: digitani on October 27, 2017, 07:53:02 pm
Well, I think I messed up.  When I put the clear coat on my Enterprise primary hull, I can see all kinds of little fibers stuck in it.  I'm not sure what I did wrong.  Maybe they were there from the piece sitting around for a while before I coated it, or maybe it was my brush?  I don't know.  They seem too short to be from the brush.

Then I made things worse by taking a paper towel and trying to wipe it off after the clear coat was just put on.  Now tons of fibers from the paper towel.  So then I wet the paper towel, and that did help, but still fibers and now I've rubbed part of my paint job off.

So my big question is... what do I do now???  Red alert!
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on October 28, 2017, 02:26:10 am
Did you rub off the paint or did you rub off the clear coat?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on October 28, 2017, 09:02:18 am
A little of both.  I was trying to rub off the clear coat, but I could see that I had rubbed off some paint in the process.  Now, the upper saucer section has part of the paint rubbed off, and probably still some clear coat left that did not get rubbed off.  The lower saucer section did not get rubbed at all, so it still has clear coat and everything, but it has fibers trapped in the clear coat, so I kind of have two problems.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on October 28, 2017, 01:55:36 pm
For the upper part, if you have damaged the paint, you are unfortunately looking at repair or stripping and reworking, depending on how bad it is.  If you could provide a photograph of it, some of us might have some ideas for repair. 

For the lower part, i have gotten little fibers in my clear coat before.  YOu may be able to gently pick them out with a hobby knife.  Having the clear coat fully dry actually helps at this point because it contracts as it dries.  This leaves a fiber sized hole in the topcoat but you can put another clearcoat over it and fill in those defects.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on October 28, 2017, 01:57:32 pm
BTW, when I see fibers in my paint, it's usually tiny pieces of lint.  You can wipe the model down with a clean, lint-free cloth before topcoating to reduce the chances of this happening.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on November 08, 2017, 05:58:39 am
Thanks so much for your reply, starsiegeplayer!

I finally had time to take some pictures.  Now that the clear coat is dry, it looks different.  There is a milky/waxy area where I rubbed too much.  I can't quite tell what it is.  Maybe just the clear coat messed up or maybe I rubbed the paint off.

Any thoughts on how to save this?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on November 11, 2017, 11:47:54 pm
Thanks so much for your reply, starsiegeplayer!

I finally had time to take some pictures.  Now that the clear coat is dry, it looks different.  There is a milky/waxy area where I rubbed too much.  I can't quite tell what it is.  Maybe just the clear coat messed up or maybe I rubbed the paint off.

Any thoughts on how to save this?

Hi Digitani, sorry i didn't see your reply until today.  I think probably your clear coat is just messed up.  If you put some water over the milky area, and it looks the same as the rest, then all you are seeing is diffusion from damaged clearcoat (dry it off after). 

If the clearcoat is the only part damaged, then just get some fine wet-dry sandpaper from your local hardware store.   2000 grit would probably work but you might need 1000 grit also. Gently sand down the clearcoat to get it more uniform (you are not trying to take the clearcoat off). Then you can recoat it. 

However, with your parts still separate like you show, stripping and reworking is not a big deal at all.  I have had to do that once (http://scifimodelaction.com/sfmaforum/index.php?topic=4049.45). 

If you had to strip it, you could use a paint stripping liquid (he right stripping liquid will depend on what kind of paint you used) but honestly to rework like this I'd probably just wet sand down the base coat with 400 grit paper until it was uniform and then repaint it.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on December 29, 2017, 05:29:50 pm
Well, I finally got back to this.

starsiegeplayer, I put some water on it, and the milky area was still just as visible, so I guess that means I will need to strip and repaint.

I used Tamiya acrylic spray.  If I sand it down with 400 like you said before, won't I be wiping out some detail on my hull?

I saw that rubbing alcohol will remove acrylic paint.  Do you think that would work?  If I do that, then do I have to do something to remove the Future first?  Also, will it remove the primer too?  Do I have to re-prime?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on December 30, 2017, 11:00:41 pm
I used Tamiya acrylic spray.  If I sand it down with 400 like you said before, won't I be wiping out some detail on my hull?
Well, it depends on where the damage is.  From the photos you posted of the upper hull, the part is all smooth, so I think you are all set to wet sand there.  If there is some detail you can protect it a bit with masking tape. 
In my Excelsior build log, you can see where I put a bad thumbprint and recovered. http://scifimodelaction.com/sfmaforum/index.php?topic=4049.15

If you have fibers on the bottom hull, you can try scratching them out with a hobby knife.  If you keep the base coat intact, gentle wet sanding with 1000 or 2000 grit sandpaper will smooth out the remaining clearcoat enough to recoat it.


I saw that rubbing alcohol will remove acrylic paint.  Do you think that would work?  If I do that, then do I have to do something to remove the Future first?  Also, will it remove the primer too?  Do I have to re-prime?

Yes, the 91% isppropyl (rubbing) alcohol (from your neighborhood pharmacy) will definitely dissolve Tamiya paint if you need to go there. I had to do that on my excelsior primary hull.  It can take a few days and you may need to assist it with scotchbrite scrubby pads or an old toothbrush.  Cover the container containing the alchohol and parts or the alcohol smell may get to you.  I had to do this on that same build. http://scifimodelaction.com/sfmaforum/index.php?topic=4049.45


Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on December 30, 2017, 11:14:10 pm
Thanks for the reply!

I was just talking with someone else from the forums and they recommended using Super Clean or Purple Power to strip it all and restart.  Do you think that is the best/easiest route?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Galaxy_Stranger on December 31, 2017, 12:00:59 am
Thanks for the reply!

I was just talking with someone else from the forums and they recommended using Super Clean or Purple Power to strip it all and restart.  Do you think that is the best/easiest route?

It's sounding to me like it didn't cure enough before you tried to fix the dust/lint particles.  If it were me, I'd blow it away with magic purple stuff or whatever to start from scratch.  I'm also inclined to reserve products like Future for the final layer of finish to complete any shine.  It will wear off, so it's not a good foundation for putting things on top of long-term.  I can't find any other information about it other than it's some form of acrylic. 

With a "normal" clear finish, like Testers lacquer Glosscote etc., you'd let the finish cure and then lightly sand out the particles with a high-grit sandpaper until everything's gone.  Then you may need to re-apply the finish depending on how much damage is done.  Otherwise, you can go through a polishing process to level out the finish.

Interesting tidbits. (http://www.swannysmodels.com/TheCompleteFuture.html)
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on December 31, 2017, 12:22:20 am
Thanks for the reply!

I was just talking with someone else from the forums and they recommended using Super Clean or Purple Power to strip it all and restart.  Do you think that is the best/easiest route?

Well, you said you were using Tamiya "acrylic spray."  Were you using Tamiya Acrylic paints in an airbrush or were you using the Tamiya synthetic lacquer (which are acrylic lacquers) rattle cans?

Super Clean or Purple power will not strip the Tamiya Synthetic Lacquers but it will not do any harm.

Also.... what were you using for clear coat?  If you were using Future, simple household ammonia will strip Future.

Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on December 31, 2017, 10:34:50 am
I'm also inclined to reserve products like Future for the final layer of finish to complete any shine.  It will wear off, so it's not a good foundation for putting things on top of long-term.  I can't find any other information about it other than it's some form of acrylic. 

Oh, so then maybe I should not be using Future as the foundation for my decals at all.  I thought I had heard others  say that this had worked for them.

Well, you said you were using Tamiya "acrylic spray."  Were you using Tamiya Acrylic paints in an airbrush or were you using the Tamiya synthetic lacquer (which are acrylic lacquers) rattle cans?

I believe it is the synthetic acrylic lacquer:

https://www.tamiyausa.com/items/paints-finishes-60/spray-as-(aircraft)-61800/as-26-light-ghost-gray-86526

I did not realize until now that there was a difference.  I thought acrylic was acrylic.

Could I just strip off the Future and give it another coat of paint, then?

I could buy some ammonia, but could I just use rubbing alchohol like we talked about before?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Galaxy_Stranger on December 31, 2017, 05:09:20 pm
First - you weren't wrong.  People use Future as a base for decals.  The idea is that you want as smooth a finish as possible to avoid silvering, (trapped air underneath the decal).  Like many things in the modeling community, opinions are divided on such usage.  I'm not telling you nobody should be using it that way - it's just not NECESSARILY the most durable solution, and you run into problems like this.  There are a lot of people that don't believe it's an appropriate final clear finish either.

On the subject of silvering, using things like Future or any other clear finish isn't always necessary - it's just a sure-fire way to get a smooth surface on the off chance that your base coat is rough.  I find that, really, flat paints, (Testers flat enamels for example), are much easier to get silvering on - but that's really because you got over spray or something else went wrong; the paint dried before it hit the substrate and now the decal is being draped over a bunch of hills and valleys with trapped air underneath.

On Paints - OK.  This is a heavy subject.  You have to be careful when using different products and product lines.  For example, you go buy some Airbrush Cleaner.  Well, there is no such beast.  The question is - what substance are you cleaning out of the airbrush.  Most "airbrush cleaners" are really assuming you shoot water based acrylic paint.  If you use Testers enamels - you're going to need a completely different cleaner.

The "Acrylic" is really referring to the Pigment material.  In our case, we're really referring to water-based acrylic hobby paints such as Vallejo, Badger, etc.   
Abrasive solvents are used to clean these out of your airbrush, but they are added to alcohol and water and whatever to keep the stench down and make them more "pleasing" to use.

Any other paint is what is known as a "solvent" based paint.  Enamel paints are solvent based, such as Testors enamels.  You wouldn't use "airbrush cleaner"; you'd use Lacquer Thinner to clean these out and can even be used to thin enamels.  A cleaning agent made for water based acrylics would do awful things and gum up enamels.  Similarly, Lacquer based paints require solvents for thinning and cleaning.

Clear Finishes adhere to the same rules.  You have to know what your finish is made of in order to properly handle it in its various stages.  Testers & Tamiya spray finishes are Lacquer based.  Therefore must be cleaned out with a solvent like Lacquer Thinner.

Future Shine is some kind of water based POLYMER.  It's not necessarily going to act the same as water based acrylic paints.  You WILL be able to clean all water based acrylic paints, including Future, with solvents such as Lacquer Thinner.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on December 31, 2017, 07:38:52 pm
A diluted solution of ordinary household ammonia is what is normally used to strip Future off floors (it even says that on the label).  I don't know what it would do to the Tamiya synthetic lacquers but my guess is that it woudln't do anything.  This could be a very nice way of stripping off your clear coat and leaving the base coat intact.

Now that I know what kind of paint and clear coat you were using, it's likely that the base coat is fine.  You probably contaminated the clearcoat and that's why its still cloudy with water on top.

91% isopropyl alchohol will go after the future.  I know this because I spilled some on my bathroom floor and had to strip the Future off with ammonia, and then recoat it. 91% isopropyl alcohol will dissolve the Tamiya synthetic lacquers (this is shown in the build log link posted above).


 



Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on January 01, 2018, 11:36:51 am
Thank you guys so much!  I feel like I have a path forward now.  I'm going to use some windex with ammonia to strip off the future, then if there is still discoloration, I'm just going to apply another coat of paint.

Right now, its below freezing and outside is the only place I feel comfortable spray painting, so I may need to wait for it to warm up a bit.  Anyone know if you can spray that synthetic acrylic lacquer in below freezing temps?  I'm just guessing that its problematic.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on January 01, 2018, 05:58:55 pm
Success!!!

starsiegeplayer was exactly right!  All I had to do was squirt a little Windex, let it sit a few minutes, wipe, and no more milky mess.  (Actually, I'm not sure I even needed to wipe.)

No repainting necessary.  Turns out this was an extremely minor problem.  I just did not have the experience to know what to do.

Thanks so much to all of you for your help!

Any suggestions on what to use as a gloss coat under the decals going forward?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on January 03, 2018, 07:30:29 am
Well, like Galaxy said, your choice of clear coat before decals is largely a matter of personal preference.  I know several very good modelers who use future like you did.  It isnt solvent resistant, but it is strong enough to use as a floor coating. 

You could easily use the testors rattlecan lacquer glosscote clearcoat (which would probably be my first choice, personal preference).  MAybe you might want to stick with future on this build since you now have the feel for it. 

Theres a nice thread ekksewhere on the site about dull coatings over future. 
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on January 06, 2018, 08:14:47 pm
I went ahead and bought some Testor's lacquer clear gloss.  We'll see how that goes.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Galaxy_Stranger on October 05, 2018, 03:25:15 pm
(https://i.imgflip.com/24fovx.jpg)
Title: Re: Oh no! My clear coat has fibers in it!
Post by: starsiegeplayer on October 05, 2018, 09:57:26 pm
Aye!  How did she turn out?
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Decoman on October 06, 2018, 07:13:17 am
Presumably, the model was left with dust settling on it, before the gloss coat was applied.

I've noticed something similar when painting models with a brush.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Guns Akimbo on October 07, 2018, 08:50:42 am
Also keep in mind that if you spray with the piece in question lying on a surface such as a piece of newspaper, cardboard or the like, air pressure can kick up tiny particles of dust and fibers that will eventually settle onto the still-wet surface.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: greg on October 30, 2018, 09:31:24 pm
I recommend getting a brush like this (https://www.tamiya.com/japan/products/74078/index.html) to dust off your model before airbrushing. It's antistatic too, which helps. For the longest time I was using a makeup brush I'd bought at the department store. I was like, "Shop smart. Shop S-Mart." But then I realized it was discharging static electricity, actually causing dust particles to stick to it. This Tamiya brush is great to have.
Title: Re: Oh no! My clear coat has fibers in it!
Post by: digitani on January 01, 2019, 08:09:48 pm

Sorry I dropped this thread for so long.

Thank you all so much for your help and suggestions!

Galaxy_Stranger, you are hilarious!  I really got a kick out of your post. :-)

greg, thanks for that tip.  Maybe I need to get one of those.

I did go ahead and coat my saucer with Testor's gloss clear coat, and I think it turned out OK, but I got swept away with the cares of life and basically made no progress for the longest time.  I'll try to post a picture of how it turned out when I have a chance.  I'm about to start another thread now about a different question, however.

Thanks again, everybody!
Title: Re: Oh no! My clear coat has fibers in it!
Post by: Galaxy_Stranger on February 13, 2019, 12:06:39 am
One thing -

starsiegeplayer mentioned using Ammonia for cleaning Future.  Be advised - airbrushes DO NOT like Ammonia!  It takes the chrome right off!  I say this on the off-chance that you'd ever airbrush Future and then try to clean it out with Ammonia.

This is something I don't see a lot of comments on so I feel the need to spread the word around whenever it comes up.  Cleaning an airbrush out once with ammonia isn't going to do much, but if you just used ammonia to clean out your airbrush all the time - it WILL star taking the chrome off.  At that point, getting your airbrush stripped and chromed would cost  more than a high-end airbrush at MSRP.

I do see a lot of airbrush artists, etc. online filming tutorials and things with no chrome left inside their airbrush.  This is probably because most "airbrush cleaners" intended for the common water-based acrylic paints contain Ammonia.  For this reason, I never use those cleaners at all.   I usually use Lacquer Thinner to clean my airbrushes out because it's handy, but you can use Oder-less Mineral Spirits from the hardware store to do the same thing, (...and it's way cheaper!).

How quickly does ammonia strip off chrome?  Someone online told me he soaked his airbrush in ammonia for about a day and it was already discolored.  I'd give it about a week or so.