Part Idea: Stored/Releasable Ball


It would be cool to have a part that can initially hold a ball and when triggered releases it.

Although it’s a hack from the available parts, I’ve been able to use this method to calculate 57+68 in 4 seconds.

I first set up a register of Ramps parallel to a register of Bits. I then set the Bits to one addend of the equation. I place balls in the back of the Ramps to represent the other addend.

I then flip the Ramps downward in succession to release the corresponding balls. After about 4 seconds, we have our answer.

Here is the video of the "computation"

I was thinking if there could be a modified Ramp part that could also hold a ball on setup and then when the active ball hits this Ramp, it also releases a stored ball in the opposite direction (if it has one). The tricky part would be timing because multiple released balls in quick succession could cause backups. However, it is an idea that provides lots of interesting concepts if it could be implemented somehow.

Ramp Hack Ideas

How timely! I was working on this as my second custom part project this weekend! I love the approach, I will keep you and everyone updated as things progress. But I would be even more excited and curious to see what designs other tinkerers come up with


I had an idea for a new piece that could store a ball in this way where essentially the stored ball would take the place of counterweight on a Ramp. There would be a small slope above the counterweight that rotated on an axle to allow the stored ball out but when the ball returned back, it would exit down the slope instead. It didn’t take long before I realized it had a major flaw… this Ramp was basically useless after the stored ball is released because it no longer has its counterweight.

Perhaps a version of a Ramp where the stored ball is in the middle so its weight doesn’t impact the functioning of the Ramp whether it has a stored ball or not. I’m envisioning a slope that the stored ball is prevented from rolling down due to a small flap that falls flat once the Ramp is tilted. This way, when the Ramp tilts back to its resting position, the flap that was holding the stored ball in place is now flat so the stored ball can roll down its slope as well.


This is brilliant and better than my initial idea for some sort of “grip” that gets opened up by the incoming ball. I’ll start some prototyping in the morning and keep you updated


Two issues with a stoed ball piece.

  1. If its release of the stored ball is triggered by another ball, then you have all the issues of more han one ball moving through your machine at once.

  2. If an empty stroed ball piece can capture a ball then yor machine just stopped like is was an interceptor


OK, I had another idea for this concept that is simpler in terms of mechanics and part design. The idea basically takes the exiting Ramp, adds a small perch for the stored ball below the center white peg (to keep balance in the center) and adds a small slope that is a mirror image of the Ramp’s main slope for this stored ball to roll down.

I tried to keep the stored ball in the center so as not to throw off counterweight issues when there is no stored ball on this modified Ramp. The Ramp would still be harder to tilt since it would be trying to lift this extra weight, however, it wouldn’t take much for the stored ball to fall off the perch, thus restoring the counterweight to normal. I tried to move the perch as close vertically to the middle to help offset this, but I still need the ball to clear the perch when the Ramp is tilted. I like this idea better than the first one because aside from the tilting of the Ramp, there are no moving parts on the piece, so it is much simpler.

Without actually testing this physically, I have no idea how feasible this idea even is. It could be that the active ball doesn’t have enough inertia to tilt the Ramp that has the extra weight of a stored ball. Or it could be that the active ball leaves the Ramp first, causing the stored ball to exit at an incorrect angle… so many things that could make this problematic, but hey, aren’t new ideas like this what this messageboard is for? :slight_smile:

  1. You are correct. There is always the potential for problems when you introduce multiple balls in the machine at once. I posited this idea in an earlier post and entertained both the problems but also the potential. This idea would not be viable in all situations. However, there may be some controlled situations where something like this could be useful. Since the Active ball and the Released ball exit the Ramp in opposite directions, you do have some control.

  2. It would be cool if an empty piece could capture a ball, but I didn’t entertain that idea with this concept. You are correct that it would act as an interceptor, but if another ball had been released prior, the program can still be running and this newly captured ball could still be released. But even so, there could be value in capturing a ball to be released on a future manual start to the program (ex. turn-based programs, etc.). However, as I mentioned earlier, my concept simply acts as a normal Ramp and will additionally release a stored ball if one was placed prior to the start of the program.


I found a way to capture a ball, and later trigger its release using another, using only parts in the box:


My 3rd iteration of this idea I was toying around was similar to my 2nd iteration, but moved the perch for the stored ball to be above the center peg rather than below it. Moving the center of gravity to be above the peg would ensure that the active ball would be able to trigger the Ramp and cause the stored ball to exit as well.

However, I never would have thought of using a pre-weighted gear bit as you have done here. And this looks like it works really well. And it means using existing parts… major bonus!