Pneumatic air compressor

[Tobaganner]

I recently dusted off my lego collection, and have started rebuilding stuff, I came across a pneumatic set, and started researching what could be done with them, I found a channel called nicjasno who makes and sells lego pneumatic engines, I am thinking about making one, but before that I would like to buy an air compressor for it, could anyone recommend any cheap air compressors that would be good for lego, I would like a small battery operated one (for a car), and a regular (portable) one, I am also interested for some building instructions for a lego pneumatic engine, 6 and 8 cylinder instructions please (I dont care if it is inline, boxer, or v).

[Milan]

Hello Tobaganner and welcome to Eurobricks!

Ales, the guy who produces those engines is a member here, by the same name...nicjasno. Maybe he will jump in and provide an answer.

About the instructions, there are few of free ones on YT with links to the galleries, or step by step videos, both 6 or 8 cylinders. 

[nicjasno]

As compressors go, You want a big air tank, or high pressure. I use a hobby compressor with a 50l air tank and a pressure of about 7.5 bars. You could go much smaller like airsoft air tanks, which have a much higher pressure.

I am thinking of improving the efficiency of the engines by designing an expansion engine, where the air goes into the first cylinder, and after expanding and doing work is passed onto the next cylinder, which of course has to be bigger, to do the same amount of work with less pressure. This would decrease the pressure needed and allow for the air tanks to last much longer. But it greatly complicates engine design, since it'll require at least 2 switches per cylinder and a more intricate timing mechanism, unless i use non-lego switches that are designed like steam engine valves.

Edited August 25, 2017 by nicjasno

[knotian]

nicjasno

That sounds like a typical triple expansion marine engine. They were beautiful things and are still available for the small boat and modeller audience. That would be a sweet model.

Ed

[nicjasno]

That's the idea. Since pneumatic engines and steam engines are exactly the same.

[Tobaganner]

Thanks for all the responses, do these air compressors look good? battery operated: http://www.homedepot.com/p/Ryobi-18-Volt-ONE-Power-Inflator-Tool-Only-P737/206159256

wall powered: https://www.farmandfleet.com/products/357736-porter-cable-oil-free-pancake-compressor.html?feedsource=3&gclid=CjwKCAjwxJnNBRAMEiwA8X_-QXDUm2wLe1xjYhT7xZNMI_kUGlGzvMPU3zqUGoaZPnZv3ZCWAjj8jBoCqs0QAvD_BwE 

https://www.searsoutlet.com//d/product_details.jsp?pid=184581&uid=33717591&storeZip=01040&sid=IDx20110411x000008&scid=scplp33717591&sc_intid=33717591&gclid=CjwKCAjwxJnNBRAMEiwA8X_-QbwlhV1scUDdYJXMP2U1BfQQ5lydC-oXOJKNnRIhecTUZGX4xr7LTBoCeREQAvD_BwE

which one of the wall powered ones should I get?

[nicjasno]

Mine is very close to this. Also with a 13 galon air tank and this one has actually a higher output psi rating and is even cheaper than mine was.

http://www.homedepot.com/p/Campbell-Hausfeld-13-Gal-125-Max-PSI-PortableElectric-Air-Compressor-DC130000/301079716

Edited August 30, 2017 by nicjasno

[Tobaganner]

Thank you for the answer, I found a YouTube by the name of OOOONeoGamerOOOO who I'm pretty sure is taking credit for your engines and showing people how to make then, check out his/her YouTube channel just in case

[nicjasno]

I know his chanel. I can't do anything about it. But i don't see him taking credit for designing the engines. So i guess it's ok-ish.

[Tobaganner]

ok

if I build something like your mustang and put the battery powered air compressor I was talking about in it do you think it will run well? will it have enough air? Also, when you build the charger, will you post instructions for it on LPEpower, and if so, will the mustang instructions price drop, I would like to use it for the suspension

Oh, and will you make a boxer LPE?

[nicjasno]

The E30 instructions will be free on LPEpower.

Using onboard compressors is dumb. I'd rather have the car electrically powered then. Much more efficient.

 

[Tobaganner]

ok, thanks

What tubing do you use for your LPEs?

And would it be a bad idea to use a pneumatic cylinder v2 2x11 for an lpe

Edited August 31, 2017 by Tobaganner

[ThatOneBuilder]

I think it would be too long and have too little power... The mid sized ones are perfect imo

[nicjasno]

The big cylinders are too big indeed, unless you need a high torque engine. In this case you'd also design the crank with more throw, to make use of the full extension of the big cylinder,

Such an engine would be very slow though. The expansion engine will probably use a small cylinder for the high pressure, the normal cylinder for medium pressure and 2 normal cylinders for the low pressure sections. I do need to see what the exact volume(piston surface area) differences between the cylinders need to be though.

 

Edited August 31, 2017 by nicjasno

[ThatOneBuilder]

I remember watching about those engines... They are very interesting.

Even though the engine with long cylinders would have torque,it would not look as good as one with smaller cylinders..

I think it's a good compromise to use smaller cylinders as they look much better...

(I don't think any of this made sense )

[Tobaganner]

ok, is it fine to use the long pistons in a rally car for suspension though?

[Tobaganner]

I would like to build a subaru impreza wrx sti, would a 4 cylinder engine be enough for it (I would make it the size of your mustang) It will be used mainly off road

[nicjasno]

26 minutes ago, Tobaganner said:

ok, is it fine to use the long pistons in a rally car for suspension though?

Or Baja truck. Absolutely.

5 minutes ago, Tobaganner said:

I would like to build a subaru impreza wrx sti, would a 4 cylinder engine be enough for it (I would make it the size of your mustang) It will be used mainly off road

This is starting to get off topic. But as long as the car is light enough, yes. The mustang is too heavy. The challenger will be much lighter, yet a bit bigger.

Weight is the bigest enemy of your lego models.

[Tobaganner]

ok, thanks

[ThatOneBuilder]

I think the thread has been solved..Maybe it's time to close it?

Anyways weight isn't a problem with xl motors but with lp engines.. yes

[nicjasno]

11 hours ago, ThatOneBuilder said:

 

Anyways weight isn't a problem with xl motors but with lp engines.. yes

Weight is always a problem.

[ThatOneBuilder]

5 hours ago, nicjasno said:

Weight is always a problem.

Oh. Well I'm a noob at this, I make manual... I thought xls has enough torque...

[nicjasno]

LPEs have more torque and power than lego motors.

The less weight you have, the easier any given motor will be able to propell the vehicle. And the less strain will be put on the drivetrain.

[Tobaganner]

how do I close the topic?

[Aventador2004]

3 hours ago, Tobaganner said:

how do I close the topic?

You can't, only admins can.