Vertical Expansion Clarification

I am planning on building a horizontal expansion mechanism but we are kinda confused

Rule SG5 states “Any extensions or combinations of extensions above 18” must fit within a vertical cylinder 2” in diameter.”

Our team has no pneumatics so we plan on using our flywheel to shoot a bunch of small gears (1.75 inch dia) with string attached. Basically, we will be using gears as ammo and we want to build like a magazine of them so we can aim before every string shot. BUT, the gears are going over the vertical ceiling when we launch them cuz of the angle

Does the rule mean that all of the gears must initially be contained in a cylinder 2 inch wide? (like a pringles can)
Or can the gears just be stored however we want?

Also, if that is allowed, why hasn’t someone built a blocking wall yet? Can my team make a wall that initially fits within 2’’ radius cylinder but expands up and out past the 2’’ width to block other peoples’ string shooters?

I don’t understand what’s your intention on shooting strings of gears out.
Is it for the endgame?


It seems to me that you meant horizontal expansion.
Vertical expansion is when you go up, so the “robot must fit inside of a tube” rule should not concern you assuming you only expand during the endgame.

However, I would like to answer a question of yours.

This actually has been done. It was one of 67101C’s (9 Motor Gang) tests for an expansion method before settling on a string launcher like you have yourself. Here is a short video of a test of the wall.

And to partially add another answer to you question of why you haven’t seen many blocking walls yet, it’s because it’s practically over engineering. String launchers can cover just as much space and if not: more.

Work smarter, not harder.
-Scrooge McDuck


I think what he means is a wall to block expansion which could be an interesting concept, so try to figure it out yourself! Make a prototype, test it, and refine it to the point where you can block expansions reliably!


There are no vertical expansion limits during the Endgame. (SG5d)

Sry I should have been more clear, I meant shooting string for horizontal expansion, but the flywheel is angled upwards, so we are considering the possibility that the gears might go over the vertical ceiling.

Since our gears are kinda going over the vertical ceiling when launches out, do they have to be stored in a 2’’ cylinder volume on our robot? ( The gears themself can fit, just we don’t want to build a tube to contain them)

I think the rule is that they have to be able to theoretically be able to fit in the 2" cylinder volume.
In other words, you should have the ability to fit it into the 2" cylinder volume, but it doesn’t have to be stored in a 2" cylinder.

Be mindful of the recent Q&A - the volume must be perpendicular to the floor tiles. Referees can check by using a 2" PVC pipe (specification somewhere …)


There is no vertical expansion limit in the endgame.


the game manual suggests using one of the roller pvc pipes as a way to check, giving the specifications of


Oh well, this kind of solves the whole issue, doesn’t it?

so that means we DONT have to worry about this whole 2’’ cylinder thing to store our gears?

Correct, unless you are trying to do something before the last 10 seconds.