I come to you extremely discouraged. Recently returned to the hobby as a casual builder after several years away, so please take it easy on me if you can.
I was just in the process of weathering a model and as I was doing so, the model began to quite literally crumble in my hands. Pieces that were previously solid plastic began to bend and fall apart in my hands, breaking and snapping at points that were not even seams. It was almost liked it melted, thick pieces were suddenly malleable, bending and crumbling in my hands.
The kit is a Bandai AT-AT. My process was the following
Primed with Stynelrez.
Painted with Tamiya Acrylics.
Gloss coated with Vallejo gloss coat.
Wash/sludge bath with Ammo by Mig.
I let the wash sit for thirty minutes and began to wipe it off with a rag and cotton swaps. It was while doing this that pieces began to bend and crumble.
It’s almost like something compromised the structural integrity of the plastic.
I have absolutely no idea what happened here and am extremely disappointed that weeks of work essentially just disintegrated in my hands.
Can anyone walk me through what happened here so I can prohibit a disaster like this in the future?
Well since it was primed then that would be the only product that actually contacts the plastic. Never heard of that primer before but it doesn’t look like it should cause an issue. Did you thin the primer with anything before applying it?
Nothing stands out there but I had something similar after stripping paint off a little 1/144 dc-3 by soaking it in testors ELO. After a few hours I pulled it out of the bath and it just kinda fell apart like you described.
I’ve found several quite old Reddit threads on /r/modelmakers alluding to the fact that enamel thinner and the thinner contained within enamel washes can weaken, crack, and disintegrate the plastic used in Bandai kits. Threads here, here, here, and here.
This kit was heavily primed, painted with multiple coats, and sealed with a final gloss coat. Would have assumed this ultimately would have been enough to protect the kit from whatever in the enamels is damaging to the plastic. Seems not.
Perhaps someone in future might learn from this thread.
Weeks of work down the tube, extremely disappointing return to the hobby.
This forum remains an essential resource and continue to appreciate its wealth of knowledge.
I’m thinking it’s your thinner? I looked up Ammo and saw it’s enamel based, what were you using to thin it? Acetone can be used and is a strong enamel thinner but may have detrimental effect on plastic if used in a slurry and left to sit. But that’s a total WAG, very odd - Please let us know if you figure this out.
Take a look at my above post. Apparently Bandai kits, for whatever reason, are extremely weak to enamel thinners and the thinners contained within enamel washes.
This is apparently a very large issue within the Gunpla community which is quite a bit larger than the Star Wars kit building community, which is where my enthusiasm in the hobby primarily lies.
The Gov is correct about the plastic that Bandai now uses. It is succeptible to enamel thinner. Sometimes it is fine, sometimes it crumbles. Priming does not seem to help, according to many who have experienced this problem. Sorry I have no workaraound. I have heard of water-based oil paints, which might help. My sympathies go to your AT-AT. The Empereor will not be pleased.
Yes their enamel washes are pretty hot,I’ve had them eat away the stubs that road wheels attach to on Dragon kits,break apart styrene Magic Tracks it definitely attacks the glue joints as well as fragile plastic.I found that you cant slop it on and work it in too hard,just a little at a time helps,it’s hot stuff.
Ahhh if they changed the plastic then my guesses are way off since all the kits I have built were older ones. Still don’t get how it works through a “heavy” coat of primer, a base coat of acrylic and a final glos coat though. That is a pile of layers to eat through and still impact the plastic. Guess I stick to acrylics for future projects.
I’ve only used Ammo by Mig washes previously which are enamel washes.
Enamel washes are different than oilwashes, correct? If the issue with Bandai kits is their weakness to enamel thinners, than theoretically an oil wash should be no issue, right?
I’ve got a tube of Abteilung 502 ABT510 Starship Filth lying around. If I’m understanding correctly, this is an oil rather than enamel paint. Could I mix the Abteilung 502 paint with some mineral spirits to create an oil wash?
If the problem was caused by your enamel wash, I highly recommend Flory products for washes. Those are all water/clay based washes, so there are no solvents needed. I ended up trying those because every other wash I tried took an extreme amount of preparation/care to use, and even then you weren’t guaranteed that they weren’t going to end up trashing weeks or months of your work. Flory doesn’t require all that brain damage to get good results with no risk to your paint work or plastic. Its just another trouble-free tool to add to your arsenal that allows you to fight smarter rather than harder.
I think I had read about Flory washes once years ago but never used them. I’ll look into them now, thank you for the recommendation.
I’m thinking my oil wash theory might also not work with Bandai kits. Found another resource that described applying white spirits to a Bandai kit and the model crumbled and disintegrated, exactly as happened to me with enamle washes.
Yup. An oil wash using mineral spirits or white spirits is going to do the same thing as an enamel wash, because mineral spirits is essentially the main ingredient in most enamel paints. Mineral spirits has a similar effect on things like latex gloves and clear Lexan plastic…Lexan will actually shatter after soaking in mineral spirits.
Flory is great stuff. I just slop it on with a big brush, wait about 30 minutes for it to dry, then wipe off the excess with a damp sponge or other similar tool. The amount of staining on the paint can be controlled by the type of clearcoat you use. The flatter the clearcoat, the more staining will occur.
Not sure where you are located, but if you’re in the US, High Altitude Hobbies in Leadville, CO is a Flory distributor that sells on-line.
I was reading up on Flory washes and was literally just about to ask if there was a US distributor. Thank you for that!
So the process is essentially
Prime.
Paint.
Gloss coat to seal.
Apply Flory wash.
Wipe off Flory wash after roughly 30 minutes.
Can a dry rag/cotton swabs be used to wipe off the Flory wash or should something damp always be used to remove it?
Also want to just take a moment to thank everyone who has responded. As disappointing as today was, it was awesome to be able to stop by this forum for the first time in roughly three years and receive so much assistance.
I feel like I’ve learned a tremendous amount from this thread alone.
Think there’s a good chance I’ll be settling on a Flory product for a full wash/sludge bath on my next Bandai kit.
I suppose one of my final questions is what about things like streaking grime, running rust, rain stains etc.?
Would something like an Oilbrusher from Ammo by Mig be an option in this case since the amount of oil paint and thinner needed to create these effects is so minimal?
From what I can tell, it looks like Flory products are more suited to something like a full wash/sludge bath rather than creating streaking effects.
You’ll need your removal tool to be damp, and remember that the type of clearcoat you use will determine how much of it stays behind on the surface of your model. If you use a gloss clearcoat, the wash will remain in the panel lines, but none will remain on the other surfaces. Semi-gloss clearcoat will result in a little more of it remaining on the surface after wiping. A flat clearcoat will result in the greatest amount of it remaining after wiping. If you want a more stained look to the flat surfaces, you use flatter clearcoats.
You also don’t need to worry about how long it sits on your model if you end up having something else come up and you forget to wipe it off. It can literally sit on your model for months and you’ll still be able to remove the excess just as easily as you would have if you had wiped it off 30 minutes after applying it.
