Answered: VEX Round Up Weighted Bases

Assembling a Round Up game kit this past weekend, I noticed a couple potential discrepancies between the instructions and the actual parts in our kit.

  • The instructions state that the pipe on the weighted bases should form a “press fit” and “require a moderate amount of force to install.” I found the pipe to be rather loose on the top of the goal such that a robot could easily remove them when trying to lift rings off. I can solve the problem with a wrap or two of electrical tape around the white plastic stub - but question is, how much? Were they intended to be designed so that robots would not easily remove the pipes?

  • What is the tolerance on the weight of the bases? The instructions state a base weight of 9.8 pounds. I am reasonably sure the scale I was using was fairly accuarate. The highest weight I could achieve, after working to get the sand to settle quite a bit, was 9.25 pounds. I am pretty sure that even with working to get the sand to settle more, I will not get another half-pound of sand in each of the bases.

Thanks!

You should add enough tape so robots cannot remove the pipes. I believe this is mentioned in the field assembly drawings. Some bases have a naturally better press-fit than others.

We will do some investigation into sand tolerance, and post an appropriate weight variance spec. Maybe your sand isn’t as dense as our sand? When you weighed the goal, did it have the pipe and pipe-tip installed?

-John

Thanks John.

Regarding the tape, I just wanted I didn’t make the pipes too difficult to come off if there was some intent that a robot can remove them if they try.

I did not weigh the bases with the pipe/tip or plug installed. The instructions read (to me, at least) as if those are installed after the base weight reaches 9.8 pounds. I guess it is possible that the sand density is that much different. I just used a bag of play sand from a local hardware store. I also expect there may be varying degrees of moisture content left in dry sand.

After further investigation it has been determined that the weight of the Movable Weighted Bases will vary between 9-11 lbs. depending on the type of sand used, how densely it’s packed and the moisture content. Teams will need to design their robots to account for this variance.