But what we're going to do is we're going to do a couple shots and we're going to get a couple different views of this area and the business end of the piston.
Well, one of the business ends. All this is one business end. It's all business end.
Anyway, here we go. So what we do is, because it's on single, it's going to close, it's going to do a shot and then it's going to open and then it's going to stop and wait for me to hit run again.
That's why it's called a single shot. We just don't have it set up for multi-shot.
We don't have an ejector plate. Yeah, we have a door open because the plastic is stanky.
So we're just going to send it.
Now it's going to go the other way.
Now comes the fun part of having to fish it out.
You guys got it? Oh, that actually wasn't that bad.
Except it's supposed to stick to the other part.
So this is what we say. We have to run a couple shots before it actually works properly.
There you go. We made a thing. Hey!
It's a little warm. Also like that air bubble though.
So there's a little bit of a color difference between these two.
I'm not sure if that'll come through or not. But that's essentially going to come down to the plastic itself.
It has been heated up and cooled multiple times. It's a little bit, like, not denatured but overheated.
So what happens is every single time you heat up a plastic,
you basically burn more of the carbon, right?
So when you burn carbon, like, it's charcoal basically.
So it goes more dark as it goes more black.
You basically want to heat it up, shoot it, and then be done, right?
If you were to take that, re-grind it, use it again, it would come out darker.
It's more noticeable on clear parts because, like, there's literally,
like, you can just see there's a change in, like, transparency.
So what did happen was it clamped.
The gate opened, the piston, like, loaded it itself,
and then released to actually shoot the shot. And then it waited for a bit for the plastic to cool,
and then it pulled the mold away, which is what it's doing now.
And the reason why it's sticking to the wrong side of the mold
is we were a bit impatient, and we didn't really wait for the mold
to get out to temperature, and we just kind of ran it. In theory, you can't run it unless this whole effect sensor's active,
so until we close that, we can't run it again. You never want to stick your finger in between the plates,
which is why we have tools. Trim removal tools for a car.
That's what they sent us. It's still not lighter.
It's still pretty dark, so that still means we have old plastic in there
that hasn't been kind of pushed through. Let's do one from here, where you can actually see the piston being loaded up.
Like I said, there's this big shock absorber-style spring,
and this Chungus motor that drives it. Robert will talk you through what he just talked to me through, because I was...
So, Robert, when I hit run, you're going to do your spiel.
So, here we go. I'm going to hit run. This is good, boys.
Look at it light as it moves. As it starts to move, you can see how slow the motor's moving with that piston.
That wouldn't be fast enough to inject the plastic just with the piston.
So you can see now the spring is compressing. What's actually happening is we're compressing the spring to build the amount of injection pressure,
and then in a minute you'll see that chain up top when that opens.
Then the spring actually releases all that built-up pressure,
and that's where you get the injection speed, because the motor doesn't move fast enough on its own to inject it just with the motor.
That little bit of chunky chunk. That's it, holding the injection, the hold pressure for a long period of time.
So it's kind of going a little bit forward, going a little bit back
to tune the hold pressure to be just correct.
And if you look on this side... Yeah, it came out on the right side.
Almost perfect shot.
Okay, someone take it out.
The reason why Robert said the motor's not fast enough
is because the plastic cools really quickly when it hits the mold.
So you have a very limited time for it to flow around the whole cavity.
So you need to go fast, but not too fast.
There's a very defined time it needs to go in,
and that's kind of why you build up the pressure. They just whack it all at once, then they're like slowly eking it in.
Because imagine hot plastic touching a cold surface.
It'll start hardening that surface, and then the actual flow will just stop.
And then if it doesn't fill the whole mold, you'll get gaps.
So imagine it not going all the way around. So on this part, you can imagine the plastic traveling through here, along here,
and then splitting, and going all the way around and coming back here.
If it was too slow, you would only get maybe that amount.
So when it splits, it'll slowly solidify, solidify, solidify, then stop.
And then it's like, oh well, you've just gone and fudged up because that's not what you wanted.
So you have to shoot it fast enough so that by the time it actually meets up again,
it is still molten.
It's not exactly the right word because it's not technically molten.
So right now, we're changing the mold out, so you probably want to get this on camera.
So this thing, it's held on by some clamps on either side.
But you just have to loosen off, and you kind of stop them.
That might be warm. It's not too bad. Is it not too bad?
It's not too bad. Don't touch this part. You can also remove the shroud.
So you can see how this part was made.
Oh my goodness. There's some shrinkage here.
Yes. Plastic shrinks when it cools.
Okay. That part made that. Now you can imagine if you can visualize what this is going to make.
So everywhere where there is a gap, there is going to be plastic.
So you're going to have this same little, we call it a sprue.
Basically, sprues go up and down, and then runners go side to side.
So this is a sprue. That's a runner. And then this is the actual part.
So what you would do is you would break this off eventually.
And that would be your part. The full square one.
Because I cut this one.
But that would be your actual part. And you would actually just get rid of that or re-grind it and use it again.
But we have the sprue coming down and we have the two runners that split into the four cavities.
And all we care about is that ring part.
So we'll end up cutting this off.
I wonder if we should get some sort of chop chop boy to re-chop this up to make more re-grind for that.
It's probably not worth it at the volume we have yet.
I know. But when have we ever done something because it made sense?
To insert this mold back in, you have to essentially more or less line up the pins.
But because it's a very tight fit, the last little bit of the insertion you actually have to do with the clamp itself.
I don't know if pasty is the right word.
They literally suggested it. Oh, okay.
Run it!
Well, I mean, it's sort of like automatic ejection. Except it's attached to the wall of fame.
In all fairness, despite the ejection, the actual part itself is getting better and better.
Yeah, the rings look great. It's not sticking to the mold side, which means it's getting deformed.
Yeah, that's what I was pretty much about to say.
Hey!
The new injection molding machine that we bought. Yes.
Inside is a 3D printed mold that makes rings. So, Robert designed a mold that we stuck on the SLA machine in high temp resin.
We milled out a pocket of a mold, and that's now sitting over there.
And now we can inject as many plastic parts as we want.
Except we're trying to figure out how it works properly because we're having issues.
Pretty crap. We're having issues. Oh, that's crap plastic.
That's polypropylene. So, it's like this plastic you can get.
It's just the least toxic, right? If we were doing ABS in here, it would stink like pretty bad.
Like with hotbox ourselves with VOC, you know what I'm saying? So, we kind of just dialed it back with like cheap plastic, but it is crap.
Okay. Okay, so if we wanted to do like a special one-off handle in some weird plastic or something.
Potentially. Yeah. Yeah.
This is basically the $70,000 optical inspection machine that can measure down to like micro and micron level.
Bye! Bye, 4.5.
Bye, 4.5.