A Sticky Lesson

In the last year or so we’ve increased our 15mm range by leaps and bounds, both vehicles and buildings. We’re now casting more and more pieces in resin and learning new lessons about the material, one of which I think it could be very handy to pass on.

B15-300

At the centre of our Salute stand was the 15mm colony base, a model with which I was extremely pleased. The display model was only finished in the last days leading up to the show. What’s not obvious from the photos is that the top surface of the building modules are a little shiny and somewhat sticky. I’d made the mistake of leaving the model in its box in direct sunlight for several hours and it had got a bit warm – the day was not all that hot, maybe low to mid 20s centrigrade, although the temperature in the corner where the colony base sat probably got into the 30s in the sunshine. This somehow affected the resin and made it ooze through the layers of primer, paint and varnish. The garage module, which I’d painted as a separate piece, suffered really badly, and the paint came off in one or two places when I touched it.

I’d also had a similar problem before when priming some advanced buildings – it was a chilly evening at the workshop so I used a small fan heater to help them dry. This ended up making them ‘sweat’ and some of the primer (Halford’s car primer, which usually sticks to anything) came off.

So the lesson is – don’t let your resin get hot! And especially don’t let resin items sit in direct sunlight for any length of time. They could end up sweating and oozing, even through multiple layers of paint and varnish.

E6912_240701_00_PP_300Wx300HThe situation isn’t necessarily fatal, though. In the case of the colony base I gave it a coat of undiluted PVA glue. This dries clear, if a little shiny, so it had to be revarnished, but it looks ok. Obviously the PVA is quite gloopy and is like putting a very thick coat of varnish on, but it did dry clear and, in the end, it’s better than having a sticky, ruined, unusable model. I used a PVA from a DIY store (Wickes) designed for mixing into plaster and also sealing dusty walls, it’s probably a slightly different formulation from the type you buy in hobby shops and so better suited to stopping seepage.