Pneumatic 'steam' engine for L-gauge

[Sokratesz]

I'm trying to build a pneumatic engine for L-gage using the wheel base from the Emerald Night. It's still a prototype but the construction is fairly simple with two pneumatic switches being thrown at a quarter offset to move the pistons:

(it's difficult to see but the two pistons have a quarter offset)

The problem seems to be the timing of the switches. Yesterday evening I had it nailed perfectly and it actually rolled across the floor at a decent pace (me following with the pump :) But I changed it a bit since and I can't seem to get the timing right, I always need to give it a little push here or there to keep it running.

Any tips on making that go smoother? Initially I wanted to build it with the small cylinders but their working range is less than 3 studs so they won't make the full circle :/

Ideally I'd want to make it a little smaller with a loc around it and run it (probably not very fast, but hey) off of a 100% lego compressor to be carried behind it.

- Sok.

[Alasdair Ryan]

I don't have any train stuff so i can't help you a lot,but perhaps if you use sariel's flashing light system,but instead of lights it could power your pistons.

Trafficators

[Burf2000]

Hey there

I made this, if I can help please let me know, I coud scan in some pictures for you

[Sokratesz]

Ah yeah you used the 24t gears, I guess the 16-t ones have too much leeway.

I was tempted to make the switch system more direct but that would severely reduce the chances of building a believable loc around it :) I'll fiddle with it some more. Do you have a pic of the exact transmission you used?

- Sok.

Edited October 30, 2011 by Sokratesz

[Burf2000]

Ah yeah you used the 24t gears, I guess the 16-t ones have too much leeway.

I was tempted to make the switch system more direct but that would severely reduce the chances of building a believable loc around it :) I'll fiddle with it some more. Do you have a pic of the exact transmission you used?

- Sok.

As I remember, there is a 24t cog on one axe that then links to another 24t cog which drives the switches. I can take any pictues you want mate, feel free to drop me a email if thats easier

[Sokratesz]

Ah okay, I guess it's just a matter of timing it all correctly. I'm still tempted to try and build a version with small cylinders just because it will look so much nicer.

- Sok.