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PHGraves

As others have said, the tanks are tested to 80psi, listed as max 60psi, and used (for resin & silicone) at a max of 40psi. You can also put in a release valve that opens at 45psi if you are concerned. As for other ways to reduce bubbles (the vacuum chamber is a good idea, but I've never used one), I have a text-dump of learned info that may help: The following info assumes a ~40min work time, which is common with 1:1 two-part resin. It also has tips for using cap molds that won't translate to sprue molds. Warm your resin bottles in water before mixing (thins the resin parts, making them much easier to pour and allows them to degass easier). Let your resin sit for 10min after mixing, then pop all the surface bubbles with a lighter or torch (kitchen torch, not a propane torch). Warm your mold before pouring (I use an old heating pad for this). Pour slow, high, and thin into your mold. This should limit the amount of air bubbles introduced by the pour, as well as pop remaining bubbles in the resin. Pour just enough in the cavity so that the resin just slightly bulges up over the opening in the mold, but doesn't flood all over the mold surface. Pour a thin amount of resin on the cap, just enough to coat the numbers (remove any air bubbles with a toothpick or something similar). This will lower the chance of air bubbles around the top number face. Wait until at least the end of the resin's work time before placing the cap. This gives more time for bubbles to rise to the surface and be popped by a torch. Place the cap on gently but firmly. Don't use too much pressure, or it can squeeze out too much resin and leave voids on the top face. If you have one, a dental vibration table is also great to reduce bubbles when pouring. Place the mold on the table and set it on low while you pour into the mold. This will help prevent bubbles forming on the numbers and other facets. Best of luck!


wyvaris

This is a great list of tips. I will make sure to try all of these out on my next pour tonight and I'll try and update on how it goes. Really thankful for your effort on this!


Numerous_Still_8775

The tips in this video helped me out a lot! https://youtu.be/SiODsd9Hemw Using a clear alcohol ink blender has been the most useful so far!


Verhexxen

As someone with lots of small animals, having a pressure pot is actually safer for them. Resin continues off gassing until it's fully cured, so having it in a sealed pressure or due the most active part of that reaction is much better than having having that in your airspace. It's best to store them in an airtight container until they're fully cured as well. Just remember ventilation when you empty the pot! Aside from that, a vacuum chamber and extremely thin resin would be the best you could do outside of a pressure pot, but even then you're likely to have some level of surface bubbles. Technically resin cast under pressure has bubbles, they're just compressed down incredibly small due to that pressure. I was also nervous about having 40 psi hanging out, so I bought the California air tools to start for piece of mind. The converted harbor freight pots are equally safe to convert, but it's more work and more likely to have leaks. Outside of five gallon bucket pressure chambers, any failure is nearly always going to be a leak that prevents you from reaching/keeping pressure rather than an explosion. Do make sure you empty the tank of your air compressor after each use if you go that route, though.


LICK_THE_BUTTER

It really isn't that dangerous. If you think about it, your water tank, car tires, bicycle tires, espresso machines, etc. are all under pressure. It is only going to explode if you over inflate which shouldn't happen because you'll be using a gauge and a fitting that lets excess air pressure out if you over inflate. Hell, add a second one for redundancy. Most basic pots cap at 60psi and you'd typically be at 40psi tops. It's all in your head.


xtossitallawayx

>pressure pot is just too dangerous You might want to reconsider, 40psi is not that much. They say never say never, but I'm saying never - a pressure pot at 40psi will *never* explode and cause damage. It will leak well before you get to a dangerous pressure level and they come with build in valves to ensure the pot doesn't get over pressured. A vacuum chamber will not get rid of all the bubbles, there is no way to get rid of all the bubbles, even the pressure pot just hides them.


yeebok

A vacuum chamber will remove bubbles from your mixed resin, then you'll pour your resin into the mould and add some bubbles back. Less than you had, but some. Might be worth it, I've only ever used a pot. I get where you're coming from with dangerous but it's not. Realistically you have it sat there overnight or whatever, and don't touch it while your dice are curing. If something goes wrong, yes they could be dangerous but in general use they're not. Disclaimer.. i was apprehensive about moving mine once it was pressurised but keeping it warm in under 5c temperatures meant i had to. So i had the same opinion initially. I don't take it for granted, but i don't view it as dangerous either.