First off thanks for all the help guys. I did once cast some models in an opaque two part resin. A lot of this sounds reasonable similar. The only question I think I've forgotten is how do you all find the fumes? Will I want to leave the work space as soon as possible? right now my workspace is also my main gaming/living space so I May need to track down somewhere else to use for a bit. By the time I moved to Infinity I had made my peace with bases. I dislike them but they are what they are. I have a local player that does Clear Acrylic bases and I do think they look good in general. They may be a go to for some future army projects. I think Ideally I would prefer something more like a plain dark grey base a neutral plain marker people just don't generally think thats good.
I tend to do my casting in my backyard shed, with the doors open for ventilation. It has lights and power and an extraction fan should I need it. PU isn't anywhere near as stinky as the resins used for fibreglass (polyester) OR epoxy resins - but ventilation is still a good thing. Oh, and some resins pretty much REQUIRE the use of a respirator (especially many polyester ones since they often use MEK as a catalysing agent) anyway. MEK is better known as "liquid cancer."
You want good ventilation (either a fan in the window blowing the fumes OUT, or a fan in the door pulling clean air IN. Both would be better. Yes, this makes keeping dust off of things more challenging.). And a respirator, and safety glasses (if not a full face shield).
This video might prove informative, he goes through many of the pitfalls and details of a few varieties of resins on the market for water effects (i also recommend his channel in general, he doesn't do sci-fi but his advice is very very practical)
Interesting video. For 1-2 mm depths, try the water by Vallejo or Woodland Scenics (or, I guess, probably multiple art brands, if we figure the matching mediums).
Do it. Once entombed in resin they'll be tough enough for even the most hardcore army transports: Wanna be there when you dump your army out on the table like a three year old.
Make sure the whole area is water-tight before you pour. If there are any gaps, it will seep out and create a horrid mess. Did a lot of water effects on the @Warsenal piece I did for the Michigan GT. Loved working with the stuff. Definite make sure you build in lots of dry time. Woodland scenics has a number of tutorials on youtube for their various products that were very helpful.
So this isn't dead. My Lunacy continues. I played around with a very small pour into an old empty pop can to see what working with some of the two part resin was like. Since that first very small pour went well I strapped up an old Bottle cap as a more straight edged base (with some rough shod tape) and did a pour over an old Kaplan that was not being used. The Kaplan was a big 1.5" pour just to see what would happen. The result? Not great but lesson learned. I did a smaller 3 or 4 mm pour over the first layer in the can and gave it a blast of heat to see if that would clear out any last bubbles. Since it seemed to, I did another layer over the top of the kaplan about 3 or 4mm thick.. We'll see what the results are like tonight. Varuna models are on their way....
I wouldn't go any further without getting access to some kind of vacuum pump for degassing your mix. The second best thing would be if you could use a bucket spinner like you'd see at a paint store. The air you're seeing is being introduced by your mixing and handling and can't really be controlled. In industry this stuff is usually kept pressurized under a nitrogen blanket and mixed inline for this reason. Running a torch over it will pop the surface bubbles but won't touch the interior... you might see some small improvement by preheating everything to an high, even temperature: model, casting form, prepolymer, curative, but physically removing the air is gonna be the big deal.
For bubble-free clear castings both vacuum de-gassing of the resin and pressure pot post-pour to get the remaining bubbles out is recommended, but even then, perfect clarity can't be guaranteed (you also need a climate controlled environment because atmospheric humidity also screws with the mix).
The manual way is to do many small pours so you can get rid of the bubbles. Tedious, but works. I don't think anyone doing dioramas like this use vacuum. It could get messy quickly and spoil the parts that must remain "dry".
I don't doubt that a vacuum pump would help. But how much does a good vacuum pump cost? $150? Thats part of the point of a project like this right to experiment and try different wierd things to see what happens. A big uncontrolled pour like I started with the kaplan is definitely not the answer. But working on smaller pours and heating the resin quite possibly is one. I did a couple other pours last night to try some other things out and see what happens. One thing is my work space is about 11C at this time of year, which is certainly not the recommended temp range. Changing my mixing style, getting some warmer weather and the like could also be helpful. Expect an update tonight or tomorrow morning...
You could make it yourself, there's many guides on the internet, a quick Youtube search gave me a whole lot, including a $30 guide MacGyver would be proud of, and Instructables has many more, including a few hand pumped ones if you wanna go to the very basics. But in general the trick of pouring the resin from a height seems to help a lot for this, plus a tiny amount of remaining bubbles would not be bad for what you want, it would even look atmospheric. Disclaimer: I haven't done any of this (for now at least, i have on the unending project backlog to replicate something like this).
That video is pretty cool but the product is only marginally better than what Red Zealot managed. I could imagine slow/small pours working to make what Mob of Blondes posted, though. If your pours were light you'd be able to pop the bubbles with heat. So, I'll endorse that
Small pours will work. You can also use a pin to pull the bubbles to the surface of each layer before it cures. Get a space heater or something to get your work space up to about 20degC. I'd suggest an oil-filled radiator type, to avoid exposed hot coils anywhere near chemicals.
I'd personally rather avoid a custom build like this in part because I dont have a proper workshop, I haven't generally worked with tools/gear like this a whole lot and partly because I dont have much storage space for this sort of gear/tools. Based on some fiddling and testing. I think Im starting to get to a good point. You can see a second layer on the kaplan here (mostly) its better but not amazing. So I tried a few more things and did a big pour on an old Chandra. Its got about half the bubbles at a much finer size. (still not ideal but not bad for a single big pour without a whole lot of changes). Basic game plan for the next test model Pre-Warm resin parts in a warm water bath. Mix slower and gentler Long decanting pour into a thin open container Apply gentle heat to help degas Second decanting pour into a better pouring container. High/Long pour into a layer of ~3mm. Apply a gentle heat again to help accelerate degasing. Finally I've gotten my Varuna starter + A couple extra one offs. Trying to figure out what to do with my Zulu Cobra but thats ok... I did a repose of the MSR Croc man to trial the look of scuba-ing. I've got the posting just about right I think but I'll need to add the flippers on now and work out a head. Edit: @Section9 can vouch for Oil Heaters being rad. We already have one but the fire escape is in my workspace and it was poorly installed. Its DRAFTY. I'd need a second oil heater to warm it up above where it is now. And I can't justify the heating costs (~$170/Month)
That looks a lot better already! Should work, just mind your work temperatures. Like I said earlier, going up a little bit in temperature can cut your working time in half. Not necessarily a problem if you have a 2 hour pour time, but still something to be aware of. The tricky part is going to be sculpting the neck. A flat swimming pose means that you are looking 'up', what would be nearly straight overhead if standing. Well, that actually makes life easier. Caulk and spray insulation foam to patch the drafts!
I did try a batch of caulking and such but Im no handyman. You're reminder makes a good point. I really not ought to be ok with a room 10 degrees below normal livable. It might be time I bug the new landlord again
