I am meantime working on a D day diorama of the 29th US Infantry Division coming ashore at Omaha beach.

I will be including a landing craft.

I have never attempted water effects before and am a bit nervous as I intend to have the craft in water.

I have obtained two part polyurethane resin to use.

i have heard horror stories of this stuff melting models?

All advice welcome.

Cheers

Gerry

Hi Gerry. You´ll get loads of different answers on a questions like this and many of them will be of great help.
No matter what, you are best advised to take a few (thin)pieces from the kit that are not used ... even sprue and paint them as you would your model. Then mix a little of the resin and practise. You´ll see exactly how the resin reacts with the plastic in your kit as well as with the paint. You´ll also get some practise. You´ll find the comments left here will then mean much more as you have actaul experience. But most importantly, you will have more confidence for later with your model.
No matter how much read online on how to do this, practical experience cannot be bettered!

Hi again Gerry. You should also note the brand of polyurethane resin you are using ... you might get a more defined answer.

I agree with the guys above. Make some tests. In my pacific dio I will also pour some water soon. I'm using a Andrea resin - it is specially created for moddelers, so it won't melt plastic. Becouse of it, it is more expensive but in my opinion worth buying.

I think you should leave urethane resin aside for now and use some acrylic gel instead. Either way, tell us more about the resin you have and what you plan to do. Dont forget to research a lot and get some reference photos of teh type of sea you want to depict (real photos, other dioramas, etc).

2 ways your model could "melt" from the resin:
1.) the chemical attacks the paint and plastic
or
2.) heat generated during curing could melt the plastic

So obviously testing is the best way to go. Curing resin will most likely generate heat, if this is a problem, pour in thinner sections.
If you want to make deep water (more than 1/4 inch) I'd say a combination of resin and acrylic gel medium is the best way to go. Use the resin to build the depth and the gel to add texture.

I've used clear epoxy resin (gedeo crystal resin) on my plastic figures and they went on fine. The figures were painted were primed with surfacer, airbrusthed with tamiya acrylics, brush painted with valejo acrylics and gunze flat coat as the final layer, this finish did not react with the epoxy resin.