Jump to content
YellowMarble

Marble High Speed Train

Recommended Posts

A row of steel 1/2 inch marbles speeds down a 200 feet long Lego train track!

At the end of the track there are a large number of bells. You'll see also a night train with glowing marbles.

Share this post


Link to post
Share on other sites

Hello,

just sitting in the office at a break I am not able to view youtube. I will try it when at home at the week end. But tell me, please, how fast are the marbles at the end of the track?

Regards

Hoody

Share this post


Link to post
Share on other sites

Oh, how cool! And the sequences in the dark - really great stuff. I need to get also some those glowing balls.

I figure out a speed of roughly 1 meter per second just before reaching the bells. Would you tell us the slope you have used (millimeter of height per meter of length)?

Share this post


Link to post
Share on other sites

In other words roughly 1,7° of angle. Do you ever think (or even estimate) friction losses? Or do you just try until you think there is enough slope to keep the balls rolling?

Share this post


Link to post
Share on other sites

It keeps rolling, regular 5/8 marbles has a low speed, a run takes more than 4 minutes. The 1/2 inch bearing balls are lots faster. I can also use 3/4 inch ball bearings, but they gone too fast and fly off track.

Share this post


Link to post
Share on other sites

That is in line with my assumptions and findings. The glas marbles are nonhomogenous and so loose energy (speed). The steel balls are nearly perfect spheres and so they gain more energy from the same height difference. And with the bigger diameter the geometry changes dramatically - reducing the maximum speed for a certain radius. I think that it is not really speed but the diameter. Just take a piece of paper a ruler and a compass (zirkel = de passer) and do a drawing of both geometris in a certain scale 1:1 or so.You will easily see that with the bigger diameter the angle of the sphere to rail contacts is smaller. This smaller angle has less lateral support than with the smaller diameter. It is exactly as with a banked curve (= to hoog bocht?). Less banking means less speed until things get critical.

Share this post


Link to post
Share on other sites

This is awesome.

That is in line with my assumptions and findings. The glas marbles are nonhomogenous and so loose energy (speed). The steel balls are nearly perfect spheres and so they gain more energy from the same height difference. And with the bigger diameter the geometry changes dramatically - reducing the maximum speed for a certain radius. I think that it is not really speed but the diameter. Just take a piece of paper a ruler and a compass (zirkel = de passer) and do a drawing of both geometris in a certain scale 1:1 or so.You will easily see that with the bigger diameter the angle of the sphere to rail contacts is smaller. This smaller angle has less lateral support than with the smaller diameter. It is exactly as with a banked curve (= to hoog bocht?). Less banking means less speed until things get critical.

I dont think it has to do with how spherical they are so much as the weight. I agree that banking is needed but i see how it could be difficult with that track.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×