engine1ear

Wow that just sent me down a rabbit hole haha. I just found out how they worked for the first time from a YT video, and that’s really cool and reminded me of one of Delton Adams’ LVEs.

Oh OK haha. It would be very cool to have an engine driven oil pump! Maybe one day someone could achieve a net zero power gain because all the power gained from the lowered friction would be used up powering the pump haha!

Hm, I agree with what LegoLord said earlier that a paristaltic pump probably uses up a lot of the engine's power to run and may even just prevent the engine from running altogether. For a first attempt, if it were me, I would settle for a drip-lube system, then let things progress from there.

You guys have me really wanting to try out a system that uses water, in my case I'm thinking for lubrication. I liked seeing that photo you shared on a YouTube community page, NFB. I've noticed that the big end of my connecting rod is wearing away at the crankpin. I knew this would happen since I didn't design that interface with any kind of lubricated or roller bearing, it's just dry. You can see the crankpin I'm talking about in this video. The problem that really makes me consider water lubrication is that as it wears out it creates plastic dust which I think is increasing the friction and slowing the engine down. I'll have to do more testing of this theory, but it might be worth some development along the lines of what you guys have been working on. Thanks for sharing all your ideas, y'all!

Oh, hopefully you can overcome the technology gremlins. It's a great community. LEGO vacuum engine building has had a renaissance in the last five years and the builders are mostly teenagers, so for the general EuroBricks audience I'll say join TBLE or other LEGO engine Discord servers if you don't mind being in a room of middle/high schoolers. No shade at all, of course. In fact the LVE community could really use some support from AFOLs with lots of experience in things like advanced building techniques as well as life advice and all the other positive outcomes that come from intergenerational encouragement. I've seen really wholesome interaction on TBLE over the years with the couple of AFOLs that have been active. And there's a lot of raw talent. Let's see it! Build and test, and even if it doesn't yield an obvious performance improvement, it doesn't mean you haven't learned something along the way! Going back to this. This week I discovered a LEGO engine innovator's video who came up with a really simple way to improve the seal of a LEGO engine head that is not messy at all. A piece of paper. It not only covers a bunch of gaps between bricks, but also gives the "combustion chamber" of the engine head a smoother surface for air to flow against. Certainly better than that surface littered with anti studs!

I believe the 3D printed sleeve I have is ABS because it appears the piston and cylinder are wearing at about the same rate. I'm not certain because it was printed for me when I was in University on a high end Ultimaker printer. But I'm pretty convinced it doesn't take any more than a Bambu labs level printer to get a workable surface finish. Then there's the idea of honing one of these sleeves with a ball hone very similar to how a real engine block is honed. I bought one of these hones intending to hone an SLS 3D printed cylinder sleeve, but the print turned out bad because of some trouble with the printer at work that day and I never printed another. I'd still like to do all that, but honestly the lower effort, the better. Print and go would be ideal for others to replicate. And that was the case with the sleeve I'm using pictured here. Now to find out if a Bambu printer can make a sleeve at that level of quality. If you're doing this, makes sure to set the seam alignment to random. TPU is also an interesting choice and I definitely want to try it. I learned from another engine builder's video this week that PLA is not a good choice because it doesn't wear similarly enough to ABS so one would be destroying the other over time, apparently. I was going to try for ABS with my printer to get that even wear. One more idea I've had is to try like a 30-45 degree print orientation just to get the layer lines something other than perpendicular to the direction of motion. Thanks for hearing me out guys, maybe you have some different ideas. That's really cool. I like how you positioned the "injector" right above where the engine sucks in the air. Perhaps, if you have a 4000+ rpm engine you could point it at the crankpin and run it full tilt to failure with and without the water injection system on. And THEN, you could compare the results to your splash lubrication system! That would make for such a cool YT video demonstrating the benefits of water cooling on LVEs - one I would LOVE to see! This is the type of connecting rod failure I mentioned in the previous post. Again, not my photo but from username stlxr on the TBLE Discord. Have you experienced this? As a side note I've never had such an interesting discussion about LVEs on EuroBricks before! Thanks LegoLord1880 for initiating, and thanks others for your replies!

Wow you actually went and made a radiator prototype! This is awesome man. Back in the days when I spent hours living in CAD world (I used LEGO Digital Designer) where LEGO didn't have gaps that could leak fluids, I made a radiator design that I was really proud of using ladder pieces to simulate the cooling fins. It's biggest flaw, as mentioned, it would have never held water haha. I went and dug up a photo. For LEGO radiators overall, it's too bad that ABS plastic is a thermal insulator (0.14-0.21 W/(m·K) thermal conductivity) as compared to say, aluminum (200+ W/(m·K) thermal conductivity) so we'd have a hard time really getting much heat transfer. It would be great to gain some data on the concrete benefits of cooling a LEGO vacuum engine. In general I think they run cool enough not to melt anything until you get to thousands of rpm, then particular places seem to show repeated failure (just from my observations of mostly other people's engine failures involving melted plastic over the years) in the crank-side of the connecting rod. I would call that the big end, but when your conrod is a Technic liftarm... So your choice of SVS engine means your cooling system might actually be mitigating this sort of damage/failure - nice! Regardless, I think there's a bright future ahead for innovations like those mentioned in this thread. Speaking of which, I really appreciate that so much! Definitely wear that badge with pride! Thanks so much for the updates on your innovations. This was really really cool to see, and I look forward to whatever you come up with next, whatever that may be! Feel free to reach out anytime! I've never thought about the contribution that the blow-by in a LEGO vacuum engine has on the whole system to reducing friction. Thank you for that interesting thought experiment! Cheers guys!

This is a really cool idea to have an active lubrication system for a LEGO air powered engine. At one point in my LEGO engine building I wanted crankshafts to be larger in diameter than just a LEGO axle so I made some roller bearings that I shared more about here. But to be more true to real internal combustion engines, it would be so awesome to have the bearings be plain oil lubricated. At one point I bought something of the sort because I wanted to seal the inside of a leaky engine head that didn't seal air well enough for the engine to run, but picturing the mess, I couldn't bring myself to use it. It might be expired by now. I'm excited to see a LEGO active lubrication system with an "oil pump"! A quick search in the Technic Builds and LEGO Engines Discord server showed the engine with the paristaltic oil pump made by user snagman in 2023 (not my creation). Hope this gives you some ideas!

This is awesome! I just talked about this idea with a friend last week and now here I find out it's been done!

Anyone down for 858 Auto Engines? I'd love to see a larger scale more detailed rendition. I'd be so over the moon.

Wow! Thanks so much for the feedback, y’all. My mind was pretty blown when the life preserver fit so perfectly on the worm gear. It still is! Clamping this engine head down is what I’ve used this bolt and nut combo for so far: https://youtube.com/shorts/hD9mpnR0UfM?feature=share

Yeah I was pretty excited when I found out. I actually learned this by emailing Matthias personally and when I asked about documentation, he sadly said that he didn't have any from that early 1985 engine. He does have one video on his YouTube channel of a LEGO engine powered by one of his wooden turbine fans. The earliest known documented one would now be Dan Hartman's that you can see here.

I've been doing some research on the history of LEGO air-powered engines of both the compressed air (LEGO pneumatics) and high-volume-low-pressure variety. I found it interesting that to build a LEGO air-powered engine before pneumatics parts were released in 1984, the piston and cylinder assembly had to utilize the close tolerance of the bricks and had inherent leaking problems. This type of engine, often known as a LEGO vacuum engine now, is quite popular still since it requires relatively few special parts. I've written a wiki page about it, but just for interest, the first known LEGO air-powered engine was made by the prolific YouTuber Matthias Wandel in about 1985. This is followed by Dan Hartman's first oscillating engine of 1986. I got to interview Erin, who built his first in 1994, without knowledge of other builders, and here's that video. Check the description for my wiki page.

Hey everyone! Quick note here: I just joined the Brickipedia Discord server and evidently there's no great ball contraption page on there. I asked the Wiki administrator there and he said he'd love to make a page for it and that they are looking to expand the articles on fan culture so they are less like just another Brickset. I've never made a module but watched a lot of videos and would love to see someone who is a GBC wealth of knowledge share that on the largest LEGO wiki site. Just a thought :D

Impressive!