- Hey guys, today I'm gonna
(soft music) take you through vacuum
chambers and pressure pots. What are they, how do they work, and when do you use which one? Now if you already have
both of these tools and you're pretty familiar
and comfortable using them, I got to shoot you straight. This isn't the video for you. If you have no idea what
these two things are, you know that they probably get air out of your molds and your castings but you don't know where to start, you're in the right spot. So here's what I'm gonna do. I'm gonna take you through both. I'm gonna take you through how
they work, the common uses, and just give you a basic
starter understanding. The key thing to keep in mind
here is that these are tools, and there's a lot of uses and a lot of nuance to them as well. That's why we're starting basic and we'll continue to put out videos giving you all the tips and tricks, all the nuances of
what, and when, and how, and everything you need to know to be successful from 100 to 500 level. But today, let's keep it simple. So how can I keep this
simple for you guys? Well, it doesn't get
much easier than this. Vacuum chamber, air out. Pressure pot, air in. Now that's not enough explanation, so I recognize that. But that's essentially how
these two things function. A vacuum chamber takes your material and pulls the air out of it
by pulling an actual vacuum here within this metal container, and a pressure pot using an air compressor with this inlet attached actually puts a ton of air into this, pressing against your
mold or your material and shrinking the air. So air out, air in but shrinking the air. Air out, air in. Did you get air out, air in? In and out, in and out, out and in. Let's start with the vacuum chamber. So a vacuum chamber uses
this pump right here to actually force air out of this chamber and subsequently out of the material. If you've mixed up a bunch
of silicone let's say, you've introduced a lot of air. Well... (motor whirs) Flipping that switch
actually kicks this chamber into high gear of getting all
the air out through this hose. That is gonna naturally
pull all the small bubbles that are within your
silicone to the surface and actually have them pop and release. So would you use a resin with this? Well, you can, but there's
a couple of factors to why you probably
normally wouldn't do that. Number one is resins often
have a shorter open time. That means that the time it's gonna take to get all that air out, by that end point your
resins gonna be firing off, and it's gonna get hard, and you're not gonna be able to use it. So not helpful when it comes
to resins most of the time. You can still get a lot of air out of your resins before you pour, but you're gonna be pouring it again which means introducing air into the mold again, not helpful. Silicones however naturally
evacuate pretty well. So using a vacuum chamber like
this gets 99% of the air out. Pouring it into the mold and then letting it naturally evacuate will get the other one. That means bubble-free
molds are pretty easy. That's the vacuum chamber. That's why we that. Now the pressure pot. This adds air, compresses
everything that's in there, and shrinks all the air to... Well, it's actually impossible to see with the naked human eye. So why would we do that? Well, we wanna do that for rigid resins, things that have a short
open time where you want that clear, beautiful
glass-like finish part but you don't have time
to get all the air out through something that's
gonna take awhile. You need to just real
quick hammer it to nothing. This is perfect, all that compressed air, that intense pressure,
shrinks those air bubbles. The rigid resin actually
fires off, becomes hard, and then they're never coming back. It's locked in like that. If you put let's say a silicone in here and tried to use a pressure
pot to cast with a silicone, well, that rubber's gonna shrink and that air is gonna go away. But the minute you open this thing back up and the atmospheric pressure
comes back to normal, that air bubble may come back because that rubber is flexible. That's why we want all the air out of it completely
with this vacuum chamber instead of trying to crunch
it down with the pressure pot. All right, so let's talk
really briefly operation just to get you started. With the vacuum chamber like this, like I said you're gonna have a pump that's actually gonna pull the air out. So that's gonna take your
normal 120, 110 power to operate, no big deal. From there, you're gonna have these two levers here and this gauge. What you're going to do is
actually close this valve that lets air in before
you turn on your motor. Once you turn on that motor, (motor whirs) you're gonna see the
air start to evacuate. That's right here, this. And when you're ready to let air back in, (air hisses) just open the valve. (squeaks) (bubbles pops) Now some pro tips when it comes
to using a vacuum chamber. Number one is make sure that
the container that you're using is at least twice as big as the material that you have inside. That material needs room to
rise up and get the air out. If you have a small container
that's filled to the brim, it's gonna go everywhere. Pro tip number two is making
sure that you have a good seal on the rim of your vacuum chamber. If the seals off a little bit, you're never gonna pull a vacuum and it's gonna be really,
really frustrating. Take your time, make
sure the lid's on center. Pro tip number three is
letting the material rise up and then fold over on top of itself. That's when you know
that about 90% of the air is out of the material. After that, a couple minutes
of runtime on this guy will get the rest of it out. And the last and the
fourth pro tip for you is if you're degassing and your material's getting really close to the top of your container, don't panic and don't freak out. All you have to do is use this valve, let a little bit of air in. It'll automatically drop back down, and then reclose it and let it
start to pull a vacuum again. So here's the basics of
how to use a pressure pot. You're gonna take the lid off and turn your air compressor on. Go ahead and put your
casted part inside of there, put the lid back on, and tighten it down as hard as you can. At that point, hopefully
your air compressor's up to a good PSI. You can attach the hose and introduce air slowly
up to about 40 PSI. That's what we recommend
here at Alumilite. But never go over what your
manufacturer recommends for your pressure pot. Keep that casting inside this pressure pot through the open time all the way to the demold
time for your product. Then release the air slowly. It's gonna be a little
bit loud, so don't panic. Release the air slowly. And then once it's
completely down to zero, take the lid off and remove your part. Now when it comes to a
pressure pot like this, this one was actually a paint sprayer that we converted to be a pressure pot. There's how-to videos on
that that you can find, but the key thing is to
be safe and be smart. If you don't feel comfortable
doing this, don't. There are pressure pots that you can buy from other companies out there that are ready to go for this use exactly. (squeaks) (bubble pops) Here's a couple of pro tips for you when it comes to the pressure pot. First thing is this air inlet right here. If you have a bunch of pressurized air entering into your pressure pod, this is gonna shoot a lot really quickly. And if you're not careful and go slow, you can actually splash
out some of the resins that's inside your casting. So be mindful, go slow, and be aware of where this
is entering your tank. Another pro tip for you is
actually test fit your mold before you start pouring. If you have a mold that's maybe close and you think you're good to go, there's nothing worse
than pouring that mold and then trying to get
into the pressure pot, and learning it doesn't fit. Test fit first, then you're good to go. Now another pro tip for you is actually to pour some silicone into the base of your pressure tank. Believe it or not, these are usually rounded bottoms,
it's actually concave. So pouring silicone in
gives you a flat surface and a surface that no resin sticks to. It's a great way to make this a very clean machine
that's perfectly level. The last pro tip for you when it comes to using a pressure pot is to fill your mold
up 3/4 of the way full, then transfer it into the pressure pot and finish the last pour. There's nothing worse
than having a full casting and then trying to get it into the pressure pot
without spilling anything. It's not a good way to go, don't do that. So there you go. That's a real quick intro for a vacuum chamber and a pressure pot. When do you use which
and how to get started? If you have more questions
which I'm sure you do, then leave a comment or reach out to us. We're gonna continue to do
videos on both of these tools to give you the nuances,
and the different times, and all the different
exceptions to when you would, and how you would, and what materials, and which one is which, there's a lot. Don't get overwhelmed, start simple, and go from there. Until next time guys, we'll see you soon.
