LegoLord1880

Or making it run off intake vacuum like the windshield wipers on old cars. THAT would be cool!

By water jacket, i mean places to mount the radiator against the block. they dont actually hold water lol. I'm gonna try making that engine again as an I2. oh, and you really do need a radiator submerged in water. An air tank will have WAY less surface area and will also lower the pressure in the air line

It looks like you already did lol. Go ahead! :) I've found it works best if you have multiple "water jackets" around the cylinder for more cooling. Sometime I'll have to borrow my dad's thermal imaging camera to see how big a difference water cooling makes

That's INSANE! I've never seen crankpin failure like that before! One time I had a piston weld to a cylinder wall though, and I keep both on a shelf as a kind of "trophy". Btw I've been trying to get into Discord to use TBLE but the stupid account verification is messed up somehow :p. I like your idea with lubing the crankpin. I just thought of a (complicated) way of doing that with my cooling system off the one pump actually. I'd have the air coming off the secondary radiator go into a sealed jar filled with water, and run a separate line out of the jar that would carry water. There is a really good picture of this in Sariel's "Unofficial lego technic builder's guide" book. Then I would tee off the water line and send one hose to the water injector and point the other at the crankpin to lubricate it.

Engine1ear has actually done that on his "life sized Lego vacuum engine" video on yt. I think its a great idea to have sleeves, but tolerances would be a major issue in getting it right, especially with how inconsistent 3d prints can be. This was actually my SECOND liquid cooling system design. The original has two radiators and works way better. With that system, plain air is pumped through one radiator submerged in a glass of ice and brine. Then the second radiator is pressed against the block. The water in the cup is what absorbs heat, the ice is to make the water colder (absorb MORE heat), and there is salt in the water to make the ice melt faster (to make the water colder, to absorb more heat. it all works together nicely). So basically, air goes through the primary radiator to be cooled, then through the secondary radiator to cool the block and fill the "water jacket" with cold air. Like I said, this cooling system works WAY better than the one in my new high performance engine( mostly because of the ice water + salt mix, and because it emits cooled air instead of drawing heat from inside the cylinder). I ran this by my dad who's worked in the HVAC industry for 25+ years, and he said it would work reasonably well as long as there is still solid ice in the glass. I'm fine with that, since these Lego engines probably don't produce much heat tbh. But it still is cool to say I invented the Water Cooled Lego engine! So why did I I use an inferior cooling system? Because I also wanted to use water injection and only have 1 pneumatic pump lol.

That's a good thought, and I can see where you're coming from, but lego engines really need liquid lubrication, just like real engines. Because of how leaky the seams between bricks are, we can't allow more leaks than necessary. The optimal engine does use air as a cushion to some extent though. When building a vacuum engine, you actually have to stretch the cylinder walls away from the piston a little so the engine can turn more freely. Then on the power stroke when the valve opens, the vacuum pulls the cylinder walls against the piston to make a seal, and THEN the piston is sucked up. When the valve closes, the cylinder walls relax, break the seal, and allow more free movement. We are dealing with around .0015 inches though, so the seal doesn't really "break", but there is a noticeable difference running an engine without cylinder stretching. This is partly why vacuum engines tend to not run as well on positive pressure. Also, like in gas and Diesel engines, the lubricant can be used to make the seal. The lubricant can "fill in" pitting or rougher surfaces to create seals, on top of making everything run smoother.

:D That's a great idea, I'll have to try it sometime! It does look like it'd draw quite a bit of power though. Since we're both lego engine innovators, I think Id better give an update on what i did and the new designs i have: The engine I did this one is a "high performance" 4x4 svs engine. Keep in mind I didn't use ANY performance designs like lightened pistons, cranks, or flywheels. Just a standard svs that I got up to 4000 rpm. You can see the mostly watertight oil pan in the picture, and the fill port where I put water in for lubrication. I use water because it makes less mess than vegetable oils, plus it doesn't leave residues, and it's thin enough to work well at high speed. The engine has splash lubrication for the bottom end, where the crankshaft dips into the water and flings it onto the lower cylinder walls. The seran wrap gasket isn't perfectly watertight though, so I have to run the engine in a 9x13 glass pan borrowed from my mom. My engine also has the water cooling system I devised, and here's where things get a little complicated. I use a pnuematic pump submerged in a glass of ice cold water to pump water through a small radiator I made. The radiator is pressed against the engine block, allowing the cold water inside to absorb minute amounts of heat from the engine. And here is the last of the 3 innovations on this engine: water injection. Water coming out of the radiator is injected into the engine's intake, which lubricates the top end. Then, the water either drips past the piston and slightly refills the oil pan, or gets sucked into the wet-dry vacuum on the power stroke. All the water action happens intermittently (bc of the manual pump), and the engine speeds up like its on nitrous when I pump water into the intake. It all works pretty well! I would love to see this stuff get put to use in other, more realistic engines (I'm talking to you, engine1ear! 🙂). I'll get some pictures uploaded and put in a link in a minute. Water Cooled Engine pics: https://drive.google.com/drive/folders/1U7hSHggFk5SBkjLve5Ibm4_0fHKgKr5v

Lately I've been working with poppet valve vacuum engines, which are interesting because of how much room for innovation there is. Today I built and tested a 3 valve head for one of my engines. It has one exhaust (fresh air) valve, and two intake (power) valves. I took tips for the head from the Cat D32 4 valve engine. The 3 valve head will make the engine run at around 1500 rpm, about 50% better than with its stock 2 valve head. Surprisingly, it's has about the same torque. I think this is because the engine has two intake valves to open. Any comments or suggestions for improvements will be greatly appreciated. I would also love to see someone use this to model International Harvester's gas-start Diesel engine, which was used in the Farmall MD tractor from 1941 to 1954. Pictures: https://bricksafe.com/pages/LegoLord1880/vvt-vacuum-engine/technic-starter-motor-prototype/kohler-k241-vacuum-engine-model/3-valve-vacuum-engine Inspiration: https://www.dieselworldmag.com/diesel-tractors/tractor-talk-1941-farmall-md-diesel-first-of-the-breed/

Hmmm. Seems like it could work, but I don't want to do anything that could permanently stick the pieces together. Maybe I'll try more plastic wrap, and between each layer. Previously I had used only a double layer on the baseplate in the bottom of the oil pan.

Recently I'e been doing some vacuum engine experiments. My engines always get more performance from using lubrication, but I'm wary of using olive oil, since it left a really gross residue on some of my pieces. Eventually I realized water would work just as well, but would need to be applied often because of how things it is. I came up with a splash lubrication system, which uses a sealed crankcase filled with water that is splashed up onto the cylinder walls when the piston goes down. It works great, but the water leaks out from between the bricks and constantly needs to be topped off. I've been using saran wrap between the layers of bricks, but I guess that's not enough. Does anyone have tips on how to seal the crankcase? Also, I would appreciate it if anyone has a water pump design to use for the water cooling system I developed. It needs to be able to pump water through a pneumatic hose.

I've been doing some experiments with my vacuum engines, and I'm trying out a splash lubrication system, using water instead of oil. An oil dipper on the end of the connecting rod and flings it against the cylinder wall as the piston goes up, and the piston is lubricated as it goes down. The only problem is, water leaks out and gets EVERYWHERE. I've been using cellophane wrap as a gasket for the baseplate it the bottom of the oil pan, and I've already accepted that I can't make shaft seals, but am I doing something wrong? Or is it just impossible to seal lego parts? Also, I would greatly appreciate it if anyone has a water pump mechanism I can use for this or my water cooling system.

Behold! My newest Lego build: a model vacuum engine. This is my best attempt at an engine with a flathead design. This engine has an 8x8 piston with a 3 stud stroke, and runs at a laughable 500 RPM. It features: -Custom heavy duty crankshaft -Removable head -Removable Valve and cam gear covers -Removable oil pan -Fake carburetor -Super heavy flywheel. Link to picture( I will add more later) https://bricksafe.com/pages/LegoLord1880/vvt-vacuum-engine/technic-starter-motor-prototype/kohler-k241-vacuum-engine-model Link for more info on the real engine https://www.tractordata.com/lawn-tractors/000/2/2/226-cub-cadet-100-engine.html

Did the video on bricksafe not work? Also, I could put on a video of it hooked up to my new vvt vacuum engine.

Here is a link to a video on bricksafe of my starter motor mechanism. It uses a semi stationary 8t gear to make a worm gear "crawl" along an axle until it engages a 24t gear at the end, which would be attached to a vacuum engine crankshaft. When it starts, the worm gear is kicked out of the way, similar to a real bendix gear starter. Has anything like this ever been done before? I'd be interested to know. Please credit me if you use or improve on this design. https://bricksafe.com/pages/LegoLord1880/vvt-vacuum-engine/technic-starter-motor-prototype

I've always wanted to build a reversable vacuum engine, but I could never shrink down a valve gear mechanism. I also thought it would be nice to have VVT for higher speeds. Eventually I thought of using a differential to do both jobs. The engine's crankshaft drives one of the differential's outputs to spin the case. The other differential output is held in place by a worm gear. Spinning the output to turn the differential case makes a 2:1 reduction, so I attached a chain from the 24t end of the differential to a 12t spur gear to get the ratio back to 1:1. This engine runs very smooth. I can advance or delay the valve timing in small increments by turning the worm gear, or reverse the engine by advancing the timing by 180 degrees. I hope someone puts this mechanism to use! https://bricksafe.com/pages/LegoLord1880/vvt-vacuum-engine

The thing is I don't want to use lubrication anymore. I've had some bad experiences with olive oil leaving a residue that would gum up my pieces. If I remember right my dad still has some silicone oil that he used to put on his guns to prevent rust. Or maybe I can devise some kind of air cooling system...

How do I keep this from happening again? I thought using 40t gears as cranks would make them act like a counterweight.

So, last night I was testing out a new vacuum engine design. It was an inline 2 cylinder, with 4x4 pistons and 3 stud stroke, and had a new base and supercharger design. The supercharger had only one rotor(most have two) in an effort to save more parts and to not use up all the engine's power. I was running the engine at full throttle with a tiny Shark household vacuum and was measuring the RPM's with my tachometer. It redlined at about 2350 RPM, then slowed to 1800, and slowed even more to 1000, idled a few seconds around 650, and died. I tried turning the flywheel to restart the engine but it was stuck. After taking the engine apart, I discovered one of the pistons was stuck to the cylinder wall. It took a few blows against the Lego table to separate the components. There was a gouge in the piston, and an orange smear on the cylinder wall from one of the plates which I made the piston from. I'm pretty sure the two parts were joined by a sonic weld from the engine's vibrations and some heat from friction. Well, at least the new supercharger worked. Has this happened the anyone else before? What might have caused this, and was it really a sonic weld? I'm Interested to hear your feedback! Here's a link to some pictures on Bricksafe: https://bricksafe.com/pages/LegoLord1880/vacuum-engine-sonic-weld

Sorry, I fixed the permissions so everyone can see the picture.

They didn't put in that little tab because it would interfere with the shift forks.

https://drive.google.com/file/d/1Rplc_ztfolJY_4FcBVGWGT810qldf8Wb/view?usp=drive_link Here's a picture of one of my latest innovations: a working hit-and-miss Lego engine. I took my single side valve engine design and modified the valve to use a cam, and made a special governor mechanism. When the engine speeds beyond a set RPM, the governor pulls away the intake cam and the engine coasts until the governor closes again. This pushes the cam back into place, allowing the cycle to repeat. I designed the valve so the 1x4 panel piece closes off the vacuum hose while allowing the cylinder to breathe freely. Under no load, the engine fires about once every 5-6 rotations. Under a slight load, it can fire every rotation like a normal 2 stroke vacuum engine. Out of all the vacuum engines I've built in the past 5 years, this one sounds the best BY FAR.

I've tried that mechanism before but it takes up a lot of parts and space. It also can't keep the stick from coming out of gear. I think I'll adapt the mechanism from the Rebrickable link I posted. Thanks

I would go for that, but I only have one old style 2L driving ring and only 2 gray 16t transmission gears. Also, I don't like how they can hold position between neutral or in gear. I guess Lego's parts designers 35 years ago didn't think we'd expect so much from these pieces of plastic. Another reason I don't go with the old style is so I don't need a billion old style extensions to use 20t, 24t, or 12t transmission gears. The thing with shifting a four speed fast is the up-right-up motion from second to third gear ends up being a diagonal motion, and I accidentally engage second and third at the same time. That or I move the stick too far on that first "up" motion and it goes into 1st gear. An instant downshift like that is a good way to break stuff, especially since I usually put reverse gears in the top-left position.

Ok, I fixed the permissions so anyone with the link can see the picture. I think your setup would work, but it's not compact enough for my liking. Wear between the driving ring and shock absorber raises some concern. Nice username!

By the way, here is one of my shift linkage setups on a 4 speed manual. The 2 sides are symmetrical, with pieces removed for visibility. https://drive.google.com/file/d/1RSKHSAS-QLBC1ZzhbdCo6_61f7QC1Omu/view?usp=drive_link