# What's the best way to fix Resin model imperfections and paint Resin?



## ModelN00b (Aug 27, 2008)

I've heard Resin is prone to bubbles and imperfections. Hot water is supposedly good to reshape a bend. How does one deal with possible bubbles and dents? If there's a small thing you need to fill what exactly do you use? Do you just use plain sand paper on the possible bubbles?
What's the best way to pain Resin? Would I need to coat it with something first in order to use some paints effectively? 

I ask because I'm seriously considering the Resin Starcraft models since I'm more interested in the painting aspect of models then putting them together (one I'm looking at is one piece only lol).


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## Auroranut (Jan 12, 2008)

Be careful if you sand bubbly resin. All you usually end up doing is exposing more bubbles!! If the bubbles are large and close to the surface, I break them and fill with superglue and resin dust. I then prime with automotive primer and sand with 400-800 wet&dry depending on the surface detail. Once the primer is applied, I fill imperfections with auto spot putty. The primer will help to fill the smaller pinholes, and the putty will take care of the larger flaws.
I find that if I use the auto primer, I can use any type of paint on the kit- resin or styrene. It acts as a barrier coat between the model and the topcoats.
Resin's a funny thing. There's different types and each has its merits. Also, if the caster is using a vaccuum chamber, there are a lot less bubbles or voids in the castings. When the molding rubber is mixed, it tends to trap heaps of air that must be removed. It's the same with resin. The major casters tend to use the good equipment but the cost can be prohibitive to the smaller casters. That's one of the reasons a lot of the smaller run kits aren't as perfect as they could be. 
I hope this helps.

Chris.


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## the Dabbler (Feb 17, 2005)

If the bubbles are small, and a lot, you can use thinned-down putty and brush it on. Let dry and sand. ( Thin it with whatever thinner it needs for that type of putty.)
For painting you can use acrylic paint straight up on resin, or you can spray with primer and then use any kind of enamels. Resins don't "drink-up" enamels like they do acrylics unless they have a primer.


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## Jaruemalak (Jun 12, 2008)

The first thing you need to do with a resin kit is wash it really well with warm (not hot) water and soap. You need to scrub away any mold release that may have been used during manufacture. Not doing so can completely ruin an otherwise fantastic paint job... the paint may well NOT cure, remaining sticky.

I always fill small holes with auto putty. Larger holes and other imperfections may get treatment with Bondo, or epoxy putty. Then sand smooth, give another wash with warm water and dishsoap, then let dry and prime. I almost always use a white acrylic primer, although some people swear by a very thin, silver first primer, covered later by a thin white primer.


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## TAY666 (Jan 8, 2000)

I will second the part about washing a kit first.
Have had problems a couple of times with paint not sticking due to mold release.
Unfortunately it doesn't usually make itself apparent until you are somewhere down the line.









You can paint resin with whatever you want to paint it with.
Vinyl is the stuff that you have to watch out for. It doesn't like enamels. It's a chemical reaction kind of thing. Enamels won't cure on vinyl.

I would advise you primer anything you want to paint.
Be it resin, vinyl, or styrene.
Primer gives the paint something to grab on to.
And is imperitive when using acrylics. As they really have no tooth of their own, and don't stick well without something else there to help hold them.

Any putty you use on styrene, you can use on resin.
I've used testors tube putty for small bubbles in resin kits many times.
I also like Aves and MagicSculp.


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## xsavoie (Jun 29, 1999)

Is that acrylic primer.Any brand in particular.When cleaning the kit before painting,is the suggestion of using Ajax with water and a toothbrush a good one.


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## Jaruemalak (Jun 12, 2008)

Ajax with water and a toothbrush is fine. Just scrub it really well in clear water to rinse off all the Ajaz residue. And I always use acrylic primer, almost always white primer, unless it's a gun or something like that. Then I usually use gray primer.


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## starmanmm (Mar 19, 2000)

Me... been building resin kits for 3 years now.

I wash the kit in a degreaser (like castrol super clean. I leave in there for about an hour tops) and then once I scrub it with a tooth brush or hand brush... I re-wash again with regular water to make sure that all the degreaser is removed.

I let it dry over night.

Give it a dusting of auto primer/filler (the best I find for any resin kit). Any pinholes I find, I open them up a bit and I use aves to fill in all the holes and nicks I find.

Reprime and repeat the steps if necessary until I am happy with the final results and then do some painting.


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## Auroranut (Jan 12, 2008)

It's amazing how we all do things so differently!! As far as stripping the mold release from resin, all I do is clean the piece in general purpose thinners. If I stuff a paintjob, I strip with the GP too. I've been doing that for years, and have never had a problem. I sometimes find that if I scrub a porous piece, I can open up bubbles just beneath the surface and cause myself more headaches than neccessary so I use a soft toothbrush to get into tight areas.
The GP can be used on vinyl too. It takes the gloss off some vinyl without removing detail, and provides a little tooth for the primer. One of the best primers I've found for vinyl is auto bumper primer formulated for the plastic body parts found on late model cars. You can buy it in spraycans from your local spare parts stores.

Chris.


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## wolfman66 (Feb 18, 2006)

xsavoie said:


> Is that acrylic primer.Any brand in particular.When cleaning the kit before painting,is the suggestion of using Ajax with water and a toothbrush a good one.


Ya really want to go the extra mile in removing mold release off a kit before priming soak it in Degreaser scrub it down with old tooth brush and then rinse really good let it air dry over nite before priming.Also type of primer that use on all my kits is Krylon primer grey or the rust color.


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## mcdougall (Oct 28, 2007)

I've been using dish soap to wash my resin pieces in ....am I wrong? Please tell me if I am... because what I know about Resin could be written on a Kleenex. I've only been building Resin kits for less than a year now and I'm still cutting my teeth on these guys
Mcdee
PS, I didn't even wash my first kit and the paint comes off when you touch it...so I'll be re-doing that one for sure, It was the Babe the Creature is carrying in that after market kit.


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## Jaruemalak (Jun 12, 2008)

Dish soap will work fine. I usually give them a scrub down with 90% to 99% alcohol, just as a final degreaser, but it probably isn't necessary. When building, for small parts I use CA glue. Larger pieces (like attaching an arm or a leg) I usually drill out a hole on each piece and use a small piece of brass rod to pin them together, for added strength. Larger parts are usually glued with epoxy, at least in my case. Fill seams the same way you'd do to a styrene kit. And you can paint it the same way you'd do a styrene kit. 

Don't let it freak you out. Resin isn't all that much different than styrene.


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## mcdougall (Oct 28, 2007)

Thanks for the tips Jaruemalak...I'm working on the Pyhonkits Giant Forgotten Prisoner of Castel Mare and the body is pretty heavy and the Skeletal legs would have a hard time supporting the weight...I'm thinking of using a 1" screw through the back wall into the body to support it,I'll pre drill of course :thumbsup: Resin is ok, but I really do prefer Styrene for two basic reasons, more pieces to assemble and Weight. :wave:
Mcdee


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## TAY666 (Jan 8, 2000)

A screw should work just fine for that.
As you plan, pre-drilling is a must.
And I also advise putting the screw in by hand, don't use a power screwdriver or drill to do it.


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## Lou Dalmaso (Jul 13, 2004)

I've seen spray primers open up sub-surface bubbles, too.

You may think you've got them all only to see one or two tiny "sink holes" open in a supposedly solid surface.

just be zen about it


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## mcdougall (Oct 28, 2007)

TAY666 said:


> A screw should work just fine for that.
> As you plan, pre-drilling is a must.
> And I also advise putting the screw in by hand, don't use a power screwdriver or drill to do it.


Thanks Tay...I'll heed your advice :thumbsup:...and I wasn't going to use my cordless drill......honest I wasn't....well maybe just a little 
Mcdee
PS...But I Won't....honest


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## otto (Jan 1, 1970)

One thing to watch for, if a piece "bleeds" oily residue after washing , your in for trouble. Sometimes resin will do that if improperly mixed..a nightmare indeed! I've heard of remedys, but cant remeber exactly what they are...getting senile..seems like you have to sand out the affected area and coat with superglue of something like that. I've only had it happen to a piece or two, and ended up scrapping the parts..


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## Auroranut (Jan 12, 2008)

I had that happen to me once. I cast some aircraft wheels and they looked OK. I primed them with auto primer and one wheel dried glossy. I threw it in my parts box and a few monts later, as I was going through it looking for something, I found the wheel with a whole stack of parts literally welded to it!! It was like vinyl melt! I checked a model car that I had fitted one of my right hand drive dashboards to, and there was absolutely no problem. It had to be the mix. These days I leave the resin parts out for a few days to make sure they're fully cured and I haven't had a problem since. I also make sure I stir the mix thoroughly. I use Procast 50/50 and it goes off in a few minutes. When I first started using it, it even went off in the cup as I was mixing it!! I've learned to work fast, but I make sure I stir it well!! 
I've heard about putting "bleeding" parts out in the sun or under a heat lamp to force cure parts, but to my thinking, I think I'd remove the offending area and fill it, the same as I do when I encounter vinyl melt.

Chris.


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