Let me tell you about the weirdest device I've ever been given to test in the name of miniature wargames. The Saltgator looks like a French press designed for Robocop, an irregular hexagonal cylinder with a syringe plunger at one end and a glass viewing window along one face. It's billed as a 'desktop safe' device for melting plastic and injecting it into moulds, primarily marketed at anglers making soft fishing lures - but you better believe I'm going to ignore the manufacturer specifications and try to use it to make wargames terrain.
I was offered a free review sample of the Saltgator by the manufacturer, and it was too weird to turn down. I did offer them fair warning: "You're marketing it as creating soft rubbery plastic, and that's really not much use for miniature wargames". They sent me the unit anyhow. In my research to try and figure out if this strange device could be any use to Wargamer's readers, I discovered a whole separate world of DIY nerdery.
The review unit came with two bottles of white goopy liquid. This is plastisol, and it's what the Saltgator is designed to work with. Chemically, this liquid is packed with floating particles of the plastic PVC. PVC is a thermoplastic - heating it up enough starts a 'curing' reaction, causing it to solidify as it cools down.
Plastisol starts liquid, so compared to the polystyrene that Warhammer 40k figures or airfix kits are made from, you can inject it at fairly low temperatures. That means it will work in moulds you could make on a home 3D printer. And it can be recycled - chop it up, reheat it, and it's good for another go. You can find more detail - and a lot of answers to other customer questions - on the Saltgator Kickstarter page.
I could see potential for the Saltgator as a tool for DIY wargaming. I don't think there is, currently, an ideal tool for 3D printing model bases, movement trays, dungeon tiles, or area terrain. Printing them with an FDM printer is slow and loses detail, printing them in resin is brittle, comparatively expensive, and has a lot of clean-up. But injecting them into custom moulds?
That might beat any of the 3D printers for detail, strength, and speed. That would be no use for one-off tasks, but a potential life saver if (for example) you're making a massive trench layout and need to create scores of copies of each component. Potentially, this is a very useful tool for dedicated Warhammer terrain makers.
Except that the plastisol available to consumers is really soft - the primary customers for it are anglers using it to make lures. There's a whole DIY scene of creators using metal moulds and plastisol (heated up in microwaves) to create fake wiggly fish and worms, adding pigments to get the colors and reflectiveness just right, even sticking on fake eyes for that lifelike appearance.
The firmer end of commercial plastisol - the kind used to make lures for saltwater fishing - might work for very thin terrain pieces like ponds and roads that benefit from a little flex. It'd need to be painted with flexible paint, though, not regular acrylic paints for miniatures. And that firm plastisol isn't easy to find on the UK market.
So I started to investigate another thermoplastic that's already easily available. You might have seen reusable thermoplastic granules in craft stores. Heat them to sixty degrees in boiling water and they will merge together and become a workable mass that you can shape by hand. It cures hard, and can be painted or cut. Though sold under a variety of names, this material is all polycaprolactone, aka PCL.
I got in touch with my contact at Saltgator, Nathan. What were the key properties for a material to work inside the Saltgator? Working temperature and viscosity - how runny the fluid is - he said. Too thick and the pressure of depressing the syringe might damage the heating chamber. The idea of hot plastic splurging out the sides of a split cylinder did not appeal to me.
PCL has a bunch of uses - it doesn't interact with the human body so it's very useful in medicine - but none of those uses involve melting it. None of the specification sheets I could find gave any information on how viscous it is when liquid. But after much searching, I found a research paper investigating how PCL copes with heat strain, which had measured its viscosity at different temperatures. I sent it to Nathan.
I got his response this morning, a couple of hours before I wrote this article. The Saltgator is rated to pump out materials with a viscosity of 1,000-5,000 Pa·s, about the consistency of maple syrup, at temperatures of up to 410 °F (210 °C). At 320°F, PCL has a viscosity below 4,000 Pa·s. My experiment is green to go.
Will it work? Will it blow up in my face? Will I end up like a Temu version of the Warhammer 40k Primarch Ferrus Manus, my hands encased in a layer of molten plastic? I'll write more once the results of my test are back in. Join the Wargamer Discord community if you want to be the first to hear of my triumphant success, or miserable defeat!