Video

In the tutorial video I used a flatplane. In this video it’s a crossplane tho :) The main difference is that the flatplane runs a lot smoother on lower rpm and can run slower in general, while the crossplane has a noticeably higher max rpm ^^

What dimension of the valve would you like to know :) The thread on the valve is size M6, so 6mm outer diameter

I do have a tutorial on my channel actually :D

Das habe ich selbst gedreht und dann einen Lego connector eingeklebt :)

Sadly no. You need bearings on that crankshaft. Otherwise it will bend and not work because the valves are not getting pressed properly and the crankshaft itself will also break or disassemble… As it’s not possible to integrate bearings on the standard LEGO crankshaft it’s not possible to use those parts sadly :(

In the tutorial for this engine i use a flatplane version :)

I know, thank you 😊

Technically speaking it’s a 180° V engine 😅

There is a tutorial on my channel :)

You can always spray some oil in the tubing or use a oiler in the air hose. The crankshaft can be oiled if you spray through the gaps between the blocks or just remove the bottom cover.

He said it was a cross plane in a reply

Flatplane runs smoother on low rpm and is easier to start, crossplane has a higher maximum rpm :) At least in case of this Lego engine

Thank you very much! ^^

I made that myself on a lathe and glued a Lego connector in the center :)

@@ShaunSchafGames43 thank you so much!

WOW! Post it on your channel and I’ll see it. I wanted to make a v12 of this too, but I don’t have the resources and tools, plus I also don’t have the time. I can’t wait if you post it, I wonder what it will sound like.

@@theofficialfluffy it'll take time cause it doesn't work😭 I'll try posting it

@@FurTh3r You already made it?

@@FurTh3r I subbed and turned notifications on

@@theofficialfluffy I hope I can do it, now you put pressure on me😂😂😂😂😂

AIR!

A 3D printed centrifugal clutch. Threw that together myself real quick. It was okay but not perfect.

Sadly the regular Lego one is not going to work :( It will bend way too much However the metal parts are optional. You can also print the entire crankshaft by using the parts of @VenturiLegoChannel However when I tried it it was not strong enough. But k printed mine in PLA, so it might be strong enough with stronger Filament like ABS

Won’t work with incompressible fluids however 😅

Heyo, I am really bad at answering comments these past vew months but your comment intrigued me. I have actually tried making a block with a tile instead of a brick before. That didn’t work tho, because the air volume was not big enough. I’m sure you know, but you need a little bit of an „air tank“ above the piston to capture compressed air. Without that the engine won’t work. But you may be right that I could decrease the volume of that „air tank“ to a minimum by filling the brick with epoxy… However I like your idea with the valve float. That has not come to my mind before and I was also wondering why the rpm seemed to stop so suddenly at 4,3k. That said, I made an engine using the „standard“ valves. Those valves use significant stiffer springs and my engine also topped out at around 4,3k rpm. However the engines from @LegoVenuriChannel seem to be able to rev a lot higher with those exact valves… But I might give both your theories a try next summer ^^

Thank you for the reply! This is going to be a long comment, sorry! You are absolutely correct about the needed volume of air above the cylinder. I must admit, I only tried it with one cylinder, and if I remember correctly, it only worked with a slightly leaky piston ring. It was just a suggestion for someone smarter than myself like you if possible, but it seems you've already tested it! I know for a fact, however, this design of filling the brick would work if we could design a one-way piston ring. If you've seen Tom Stratton's video on optimizing an air engine, you'll know what I mean. That type of seal would be so beneficial to these engines because they wouldn't have to work against the air pressure on the up stroke. Anyway, in the next part, I thought I'd try to give you all my advice from what I've gathered from making these engines: First of all, I've only experimented with the "normal" Schroeder valves that you mentioned. I've been able to get both a V4 and an opposed 4 cylinder engine up to just over 6000 rpm at about 70 psi. After 70 psi, the engines do not gain any significant rpm at all, similar to yours. The V8 that I made did not work very well at all. This was due to the axel bend in the crankshaft from the first bank of cylinders to the last using the flimsy lego crankshafts. Your V8 design is much better because of how compact it is and how sturdy the crank is. Nice Job! I would love to build a crank like yours, however I don't have a 3D printer, and I've been busy with college lately. Anyway, My V4 engine works great, except when I push it past 5000 rpm, then it starts to eat away at the connecting rods. My cylinders and valves are of my own design, with flexible epoxy covering the top half of the body of the valve. This way, I am able to adjust the length of this pin stick out, without any leaks or disassembly. The downside to this being the engine is 2 bricks high and a plate piece. Less compact. Some tips I have for you may be to oval-out the exhaust ports laterally, and drill them slightly lower. When I did extensive experimenting with one cylinder, I found that with air pressure pushing down on the top of this piston, it actually hits bottom dead center further down than you may think, especially with these engines being lego and slightly flexible especially at high pressures like we are trying to push them to! With my 4 cylinder engines, I've also optimized each cylinder to be the best they can be with a test stand I made, finding the best pin stickout length to achieve highest rpm. I'm sure you know how finicky and (usually) frustrating these engines are, so don't be too hard on yourself! I must give credit to you with your impressively low idle speed on these! I can't get mine to idle as low as yours. I would love to do some more building and experimenting with your compact valve design, we'll see... @@ShaunSchafGames43

Yeah that would actually be really helpful 😅😂 I’ll let you know once I figure that out xD

Only if you also installed a pressure controlling valve. If you just used the cartridge on it’s own, everything would blow up. Also a cartridge has very little volume of air inside. That means it would most likely run only for a couple of seconds…

I used a normal workshop air compressor with an integrated air tank :) You can get one at most normal hardware shops 😅

@@ShaunSchafGames43 I see thanks for the reply:)

Thank you very much :)

I ran the engine on 8 bar down to, I think it was ~1-2 bar… so about 116 psi down to ~15-30 psi

Die Ringe sind Ø4x1mm :) Im Video zeige ich die O-Ringe bei 52:50

@@ShaunSchafGames43 ja hatte bisher nicht genug Zeit um das ganze video ohne skippen zu schauen xD

Thank you very much! ^^