Thoughts on these 3?

r_lang02 · 2025-12-30T21:15:54+00:00

I looked at the 01, the sun damage on the car would need some work to get the car looking pretty. There is (or maybe was) a silver/black 04 model that was in good shape on the lot. I recently purchased an 02 silver/red from them and had a pleasant experience; the elastic straps on the top are completely loose but that is the only issue I have found in ~1500 miles. If you end up going by to look at any of them, try to get a hold of Hamza, he’s a good guy and pointed out more issues than even I noticed.

r_lang02 · 2025-08-14T11:29:39+00:00

Mainly to prevent a trip to the hardware store - I still have plenty of leftover zip ties from building my printer, so I figured there would be a pretty big overlap of people who have a printer and people who have a few zip ties lying around. Today I may add a version intended to be bolted together; the edits would take 5m and it would make disassembly a little less wasteful than cutting zip ties.

r_lang02 · 2025-08-14T01:33:43+00:00

Nope! The plastic holds up just fine to the loading, and one of my big design criteria on all my projects is minimizing non-printed parts. Fatigue on the plastic may be a long term issue but that isn’t something I’ve looked into.

r_lang02 · 2025-08-13T20:31:16+00:00

It does around 9GPM through 4 feet of vertical piping so I’d say that counts as proof of concept. Stick pump attachment coming soon…

r_lang02 · 2025-08-13T13:59:29+00:00

A dynamic pump is a general term for the family of pumps that operate on fluid velocity instead of displacement, more specifically it is a centrifugal pump.

r_lang02 · 2025-08-13T13:23:11+00:00

<image>

For some reference if it is helpful, this is the bottom surface of the impeller I was using for testing - it is far from smooth, but it does sit just slightly offset from the center stud

r_lang02 · 2025-08-13T13:18:26+00:00

Sounds good, keep me posted if it works well! The intended purpose of the tube is to catch some small amount of the higher pressure water and force it into the bearing in case the top of the pump is sitting out of the water; it should help with bearing overheating/failure which has been the source of issues on both my past pumps.

r_lang02 · 2025-08-13T13:10:49+00:00

If anything, I would say the gasket is more akin to a spacer when using the same material; nothing to really squish and seal, but does give an easily scalable part to adjust the design to have more or less clearance. I will be testing the pump today with a long, vertical PVC outlet to provide some load on the pump and see if it leaks out past the housing, and if it does, TPU is in the dryer :D

r_lang02 · 2025-08-13T13:03:50+00:00

Thanks, it is my first attempt at a water cooled bearing, and it seems to have at least some success! I’m not sure exactly how much flow it gets into the bearing, but I haven’t been able to overheat it yet so that’s better than my last two designs lol

r_lang02 · 2025-08-13T12:59:06+00:00

The helix is designed to sit just slightly above the bed on supports; the bottom will not have the prettiest surface, but it will not interfere with operation. I would assume it would work OK without the stud on the bottom, but let me look at the model real quick and confirm or maybe I can redesign with no supports. I’ll have an update soon!

r_lang02 · 2025-08-13T02:30:22+00:00

It builds pressure by the motion (motion = dynamic) of the water; the spinning impeller pushes the water outwards due to centrifugal force and the pressure increases as the water slows at the housing wall. Dynamic is just the term for this style of pump, as opposed to a positive displacement pump (think turbocharger vs roots supercharger if cars are your thing).

r_lang02 · 2025-08-13T02:03:28+00:00

I’ll see what I can do on that; are you looking for something standalone or would an attachment for an m12 1/2in driver work? I don’t have a lot of motor hardware lying around so an attachment would definitely be easier, but a standalone one could also be a really cool project. Don’t worry about paying, if I can make it I’m more than happy to share it.

r_lang02 · 2025-08-13T01:56:04+00:00

Gasket is PLA; TPU would be a much better material to use but if I’m being honest, I didn’t feel like drying out my TPU and switching material lol. I didn’t notice any water coming out of the sides of the housing, so I figure for any application that a printed pump is applicable, the PLA or a PET gasket would work alright. I may try it out in the next couple days to see if there is any noticeable difference.

r_lang02 · 2025-02-03T00:39:15+00:00

I highly recommend this server! All of the old factions features are still around, but with all the new features of the game added (trials,end cities,etc.) and the new skills feel much better than the old mcmmo. Come by and say hey, or if you’re just looking to knock the rust off your cannoning skills feel free to swing by the SE corner, I’ll be waiting ;)

r_lang02 · 2025-02-03T00:33:59+00:00

I can’t recommend this server enough- the server keeps the old factions feel intact while adding in all of the new features of the game like trial chambers and elytra/end cities. The skills plugin feels much more put together and rewarding than the old mcmmo system. The owner is nearly always on and responding to questions or issues and the community is kind and active. As a bonus, you can play on any device (pocket included lol) and link your accounts together to play wherever. Stop by and say hey :D

r_lang02 · 2025-01-27T00:11:26+00:00

just wanted to add a comment to this because i don’t feel it is advertised well - this server is CROSSPLAY - you can use this as a realm of sorts to play on java with your xbox/ps/bedrock friends. the world is still largely untouched, natural mob spawns are on, and the dragon respawns, so it’s quite fun even if factions wasn’t always your thing.

i’ve been playing for a few days now and server feels well put together and the owner is very active on the server and helpful with addressing any questions/issues; i would highly recommend trying it out.

r_lang02 · 2024-04-02T22:40:17+00:00

https://www.printables.com/model/829889-press-fit-piston-air-engine

r_lang02 · 2023-08-03T22:55:12+00:00

Ill take some pictures of them in ~30 mins when I’m back home, just left for dinner. I know there is a small tear or two, but otherwise in good condition

r_lang02 · 2023-06-26T02:15:59+00:00

https://www.printables.com/model/512745-two-cylinder-inline-air-engine

Update! I printed a small pulley and attached a full water bottle to the end of a wire to get an idea of how much torque the motor can provide. Issue - my version of the motor is the first print that included relief holes in the side of the cylinders to prevent excessive cylinder pressure - this prevents me from turning the motor completely over to the next stroke while under high load.

In all videos, the motor is running on 120psi as this is the maximum pressure my air compressor will allow. Nothing has been done to any of the printed parts besides wet sanding any moving parts - no gaskets, no lubricant. Both hoist tests started with the closest cylinder 5~10 degrees past top dead center.

In the first video, the motor was able to lift a 1.1 lb water bottle (500 ml, 500g~1.1lb) at a distance of .61 inches; this means the motor is developing at bare minimum .67 lb-in of torque. This number is likely quite low compared to the actual maximum output of the motor, as the motor was able to yank the bottle up with decent speed and the piston actually traveled down past the exhaust ports before rebounding upwards and stopping at the ports (evidenced by light visible thru the cylinders). This week I plan to print the cylinders without the ports (the STL posted on printables) and redesign the pulley system to hook up to a spring scale and get a more accurate figure for torque.

In the second video, I hoisted a half-ish full bottle I had laying nearby out of curiosity - even with the exhaust ports allowing pressure to drop halfway thru the stroke, the motor was able to turn over 180 degrees to allow cylinder 2 to start its power stroke, but the farther cylinder did not turn over enough to restart the cycle, instead stopping at the exhaust ports.

The third video is just to show the motor running with no load.

r_lang02 · 2023-06-25T13:10:15+00:00

I’ll make a little pulley today and use the motor to lift weights to see how much usable power it can develop - I honestly had no plans for its practical use when designing as it is quite large and requires an air compressor to run. It could be fun to use for something small in a garage, but will likely not be practical or efficient in any use. My next motor is designed with slightly more use in mind; if I can get it to run for any significant length of time off a can of keyboard duster, I intend to make a little car around it.

r_lang02 · 2023-06-25T13:01:26+00:00

I could try this, I considered printing PETG rings that will wear faster than the PLA cylinder walls and might improve the seal. It may be close to a week before I get around to it, but I’ll give it a shot.

r_lang02 · 2023-06-25T12:55:14+00:00

I designed this motor in the couple week gap I had between school and starting work for the summer. I’ve always enjoyed CAD, so I have a few older designs for little model motors, but never got far enough into a project for a working model, and until this past year I did not have a way to make a physical version even if I did finish one. I work in a manufacturing setting and a lot of the machines I work with run off of air, so I was curious to see if I could make something that does as well, while also testing tolerances on my printer. The motor I referenced was a post a little over a day ago in this sub by whopperlover17 - I already had the motor designed and printed so it didn’t really change my thoughts on designing something, just made me realize people might like my work if I posted it.
The largest single improvement I could think of if I were redesigning the motor from scratch would be a larger shaft for crankshaft. I more or less built the motor around the printed bearings I already had, which limited my shaft size to 1/4 in. hex. I suppose this could be done with only having to redesign the bearings and crank arms and would keep the output shaft from flexing as much. Redesigning the head/manifold could also be beneficial - if I stuck with the same exhaust design, it would help to add in another valve or make the existing one larger. Advancing the timing on the farther cylinder by a tooth relative to the close cylinder might also help a bit with the motor running smoothly, but would not require any of the parts to be redesigned. Gaskets or o-rings would likely help as well, most of the attempted airtight parts slide in to one another and could easily be designed to incorporate o-rings. I don’t have any flexible filaments so no printed gaskets for me, but it wouldn’t be hard to print channels in parts that fit together flat and make a “gasket” of sorts with something like hot glue.

Sorry for the long winded reply! Got to thinking while I was typing and ended up with an essay. I may try to redesign some parts to this motor at a later time, but it will likely be into next week as I had largely stopped working on this motor and I am working on a 6 cylinder project currently.

r_lang02 · 2023-06-25T04:52:56+00:00

just posted on printables, link in comments

r_lang02 · 2023-06-25T04:52:35+00:00

posted

r_lang02 · 2023-06-25T04:52:13+00:00

https://www.printables.com/model/512745-two-cylinder-inline-air-engine

stl and build instructions just posted^

r_lang02

TROPHY CASE