Gap Consistency

[kylg]

Like pretty much all roller coasters, mine has multiple gaps but consistency is an issue. How do you guys collect the ball after a gap and keep it consistent enough so that it can go on the next ramp the same way each time you run the entire coaster?

[vehicleguy]

Honestly, it just takes a lot of practice and trial and error. I can't give you a perfect answer because I don't know what your jump looks like, but try experimenting with adjusting the stiffness of the landing, angle of the jump, etc. What are the problems with the gaps? Does the marble bounce when it lands or is there anything else that happens?

[kylg]

There is a varying degree of power at the end of a gap. I have a track at the end that diverts the ball to the 2nd gap but in order for this to happen, the ball must get up the track. Sometimes due to this variance in velocity, it doesn't make it up there and doesn't get to the 2nd gap.

[hippo9]

Also, I would suggest "funneling" in the ball to increase catch consistency.
Something like this:
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/ \
/ \

EDIT: Click reply with quote to see it with better formatting.

[Crtomir]

Try airsoft ammo (plastic balls) with bent PVC pipes. You cut the PVC pipes in half longways to avoid having an enclosed tube. Then you heat it gently over a heat gun. When the PVC begins to soften, you bend it. That can be your launch track, but you have to have the vehicle (airsoft ammo ball) start at the same spot on the PVC pipe every time, so build a starting gate out of balsa or something and glue it to the PVC tube so the ball rolls from the same spot every time. The airsoft ammo is light weight and will not shake your roller coaster device. Remember, vibration is BAD. You lose both energy and consistency with vibration.

[kylg]

how did you cut the pipe lengthwise? Also, dont bb's have cast marks on them that make them roll inconsistently to some degree?

[IvanGe]

how did you cut the pipe lengthwise? Also, dont bb's have cast marks on them that make them roll inconsistently to some degree?

I used scroll saws to cut my pvc pipes.

[hippo9]

You could probably just feed it through a circular saw, but I'm not sure how well that would work.

[Crtomir]

how did you cut the pipe lengthwise? Also, dont bb's have cast marks on them that make them roll inconsistently to some degree?

I used scroll saws to cut my pvc pipes.

Yes, we used a scroll saw mainly. I think some teams use a bandsaw or tablesaw. A circular saw wouldn't work and be dangerous.

Metal BBs were not so good, but airsoft BBs seemed to be better. I was skeptical at first, but out kids tried them and wanted to use them.

[kylg]

So you found that plastic bb's were better for you? Did they come perfectly round or did you have to sand them.