CmdrByron - thanks!

I don't think I would trust a cylinder design that relies on friction to hold that kind of load - for me it has to be either pins or a threaded bolt!

Here's my progress on the 5 ton plates. Having acquired some new polyurethane resin I got busy yesterday doing casts at a rate of one every hour or so (working between times) and I'm really happy with these casts... so much so that all my other ones are going in the bin.

I have ordered some RAL 1007 spray paint which should have arrived today (Amazon Prime) and once they're painted I will need to figure out how to get the warning triangles on them... I'll probably paint them the old fashioned way with masking tape and a brush!

I have cast eight in total and have enough resin left for another two, after which time I'll probably call it quits. Total material cost for all this is about £12 including the paint, so that works out quite a bit cheaper than the YCC ones.

Holy crap! I would sure like to learn how to make a mold like that. Is it made from plaster? I have never used resin before so I am totally clueless when it comes to molding model pieces.

Oh, be extremely careful working with isocyanates. That is really dangerous stuff if you inhale the vapors.

Truly amazing work Davie82.

Thank you guys - it's much appreciated. Paul I would love to "mass produce" these but it'll have to wait until I have more time to perfect the process and iron out the problems. As it is, I'm running into problems with painting because something in the resin is attacking the paint and causing it to rupture very slightly in places. And these are nowhere near YCC quality, which can't be stressed enough - this is very much a part of the hobby for me, and very much trial and error! But I am extremely pleased with how these turned out myself, especially after finishing them up.

Here are a couple of pics showing the finished plates and a closeup of the surface anomaly caused by the resin reacting with the paint. The only thing I haven't done is varnish the warning triangles to give them a protective layer.




Don, the mould is made from RTV silicone and is the simplest form of mould possible: one piece. The counterweight parts are completely flat on one plane, e.g. no protrusions (relief detail is OK), so they can be cast in a one piece mold from the bottom up. I just fixed the custom made plate to the bottom of a small box I made from styrene, and filled it with silicone. That's all it takes for a mould like this; after that, it's a simple case of pour resin and demould, rinse and repeat! The silicone is cheap and takes about 6 hours to cure, but the drawback is it will degrade with each cast because the resin cures by exothermic reaction. Eventually the mould will become brittle because of repeated exposure to heat. My plan for future projects is to get some of the more expensive silicone (addition or "platinum" cure) which will last considerably longer.

I hadn't done any casting until about a year ago, and I learned pretty much everything by watching youtube videos. Jason (hummer13) was very helpful and has a lot of experience in that area, as do other model builders on this and other forums. Experience is the best teacher, and you learn by doing... truer words were never spoken!

Thanks Jason! No pressure casting yet - the resin I bought seems to be of very high quality and it doesn't take in much air when mixing, so hardly any bubbles at all in the final parts. But I'm using extremely small amounts for each cast, about 12g in total.

And yeah that silicone is expensive... mine cost me about £50 for 5L, just over a gallon, which is equivalent to around $75.

Thanks Diego - that's helpful to know. I think you're right that it's all down to mixing, and it's really hard to mix the resin properly when you have so little time. I have about 30 seconds to mix my resin and then another 30 seconds to pour it before it starts to set.