ziggah
1
I’m making a steam engine which will be 100% 3D printed. Well, the boiler and the main valve won’t be, they’re going to be made from copper.
The rest of the engine will all be water cooled. Kinda like PC cooling, it will have a closed loop. What are your material recomendations? Just normal PLA? Polycarbonate? Or should I go fancier with carbon fibers?
2 Likes
Asuder
2
Sounds like a cool project!!
I don’t think that 3D printing is right for this project. For starters your are thinking of using hot steam, that could melt the plastic and even cause splits in the parts. I’m guessing that your engine will need a fair amount of pressure in the system to make it work. With the pressure, Heat, and the plastic it seems as though there is a lot of room for error. One other problem might be sealing the system.
Hope you can get your project working!
I don’t think anything other than metal and keeping safety in mind with proper research. Typically you would need to have a melting point way higher than pressurized steam could ever generate without detrimental effects to the material over time. If you had done your research, you would already know the material limitations of plastics, and watercooling a pressure vessel made of plastic is not possible.
ziggah
4
water cooling is possible. Why is cooling Pc’s possible, if you get water on circuits, they get ruined? Oh, yea, you put the water block over the component instead of directing the water straight on the electronics.
Again, the boiler would not be printed, and after it would be a valve, so the engine will be under only about 2 psi or .25 bar.
This here is a T section for steam. The steam goes through the big hole in the middle, and water goes in the hollow part BETWEEN the steam tube and the outside.
I’m afraid one engineering solution might not translate well into another (Something about thermal conductivity and warping), but never let it be said that it can’t be done by someone who is determined to do so. I hope that you can find plastics in your favor, and wish you best of luck and safety, even at 2 psi.
ziggah
6
I tryed blowing into a digital pressure gauge and got .179 Bar. Which according to google is 2.6 bar. True, It felt like I was going to get a stroke, but if the thing can withstand me blowing into it as hard as I can, it will most likley withstand the 2psi that I was planning, which is less than I can blow.
Har har. could have worded that better.
Anyways, A quick search on youtube showed that I wasn’t the first person to try this out. If their ABS can handle 2psi, so can mine, I guess. The problem is, they all used air compressors to power theirs. So I can’t tell if ABS will work.
Especially now that you mentined thermal conductivity. It obviously won’t conduct heat as well as metal. But another bit of info I left out is that the wall between water and steam pipes is 2mm, making the total pipe width of almost an inch.
Taking into account that steam is 100 deg C( unless superheated) the temperature differential is say 100 deg C for PLA, or 130 for ABS. That should be plenty of margin for stability of the print. With water cooling of the parts, this should work fine. Using ABS would allow for chemical welding of the parts, and somewhat address the sealing concerns that were brought up. Note: Even low pressure steam is dangerous. Safety first.
The thermal conductivity will come into play where the metal and plastic meet. You’ll need some sort of heat break, or an intermediate material that won’t transfer heat to the print. There are a lot of interesting concepts to look into!
Polycarbonate is ok for engineer,It is so strong with high strength.I suggest you could have trial PETG filament.
ziggah
9
Should correct myself:
and got .179 Bar. Which according to google is 2.6 PSI (not bar).
