 I just made these two propellers if you want to see it was in a recent video and a few people have asked about this spiral shape that I used Go over that real quick. All right, so what is the point of these fancy? Spirally things I made why don't I just use flat propeller blades or like what I usually do which is just like bend a piece of metal to like approximate this shape well when you actually get a good spiral it has An effect that I'm going to attempt to demonstrate right now All right, so the spiral Turn would be turning through the water right now. Let's pretend. This is some of the water. Let's put it here And as it rotates Notice that it moves the water up all at the same rate So Get that view So as this turns it's moving the water all at the same speed right now by propeller blades We're not a really good spiral shape. It would move the water, you know at different at different rates Now why is that important? Oh? And if you need fancy terms when it's all moving at the same rate you end up with laminar flow And if it's not moving all the same rate you end up with turbulent flow So anyway, what are these laminar laminar flow in turbulent flows? With what's important about them? Okay, so in laminar flow You have all the water being pushed back at the same rate So it all kind of kind of stays straight and going in the right direction, right? Now with turbulent flow if you've got if you have the water moving at different rates This there's going to be this part of water is going to end up having a low pressure zone right there Because it's moving slower than this part so this part is going to end up curling in to fill in some of that space And you're going to end up with a whole bunch of little eddy currents are called a whole bunch of little tiny tornadoes So we end up Wasting a lot of energy from your propeller stirring up the water Which is not that useful if you're trying to go somewhere. All right. How is that? Did you understand what I was talking about? talk All right, my esteemed assistant here wanted me to show what would happen with a flat propeller blade So let's do that. All right. Here's my pivot point and this would be turning like this, right? So let's put our water here and see what happens so you can see the The part further away from the center is moving much faster than the middle And so you end up getting water tumbling around like this instead of just going So you end up wasting a bunch of energy now another thing about these These specific spiral shapes the ones I specifically made is that I didn't make them I didn't keep the same pitch the whole way up. So I glued a bunch of pieces of wood together and The space The space from this one to this one. Oh Back myself into a bad grammatical corner. Okay As I glued them together I increased the distance here by a couple millimeters on every one So this one's one distance. This one's a couple more millimeters more This one's a couple millimeters further and further and further so instead of just going up in a straight spiral It ends up curving a little bit. I'm exaggerating with my hand, but it makes like a foil shape now Another benefit of that that I wasn't thinking about at the time was that allows me to make To make different pitch propeller blades Since this varies in pitch I can pick any spot along here and get a different pitch propeller blade Now next time I make these I'm gonna make it keep going like all the way down until it gets to like ridiculously high pitch And up here, I'm gonna make it keep going lower and lower until if the pitch is almost flat So that way I can pick anywhere along this whole curve to pick different pitches to make To make all kinds of pitch propellers And that's great stop, what is this baby doing? Yeah, I still want that dude the silver paint is pretty nice