Scuffed Balls

Has anyone else had issues with refs issuing DQ’s for scuffed balls?
We had a tournament this weekend where this came up. We talked them out of it, but they said we would probably be DQ’d at State if we had the same problem.
We have flywheels, like many others, and they will eventually start picking away at the skin of the ball. However, the foam is never dented or cut or anything like that.
The event organizers were great and worked through it, but we are concerned about State, and hopefully, World’s.
Here is a pic of “damage” after a match. One issue is that we score fairly high in matches, 200’s to low 300’s, and are probably shooting more balls than average.
Also, this type of ruling seems hard to determine since the team before you could have damaged the ball and then you scuffed the outer membrane off.

I gave them this thread, at the bottom, to review Karthik’s answer:

That’s not very bad at all. Our other teams that have flywheels scuff the balls so much that they have to vacuum the tiles every 20 minutes.

We can score 220 or so in a match (by ourselves) but our flywheel has never ripped any pieces off of a ball. Pretty sure there is a rule about damaging game elements? I know that if I was the event partner I wouldn’t be happy to have the balls wrecked by the end of the day.

Well if you want to avoid scuffed balls then don’t use your field for a practice field as a tournament. Your balls will get destroyed and your tiles will literally become green (yes literally).

Speaking of what happens to balls on practice fields . . .

Tournament: Dream It. Do It. Northern Minnesota VEX Robotics Tournament in Bemidji
Max Score: 213
OPR: 123.24
Average Team Score: 147.2
Number of matches where team score exceeded 220: 0

In the first picture, I’m seeing ball dust, but there is a larger chunk there.

In the two jpgs posted by Highwayman, something ripped the chunks out. Karthik was clear in his post

ya its the same at our school we have 3 more teams and the have to do the same.

Yeah I was told about this case personally we don’t really know their intentions because if the team that did this did it on accident using their robot you would think that it would happen again to them at that competition.

We joked that maybe someone wanted to sample the density of the ball lol

Remember the practice field at Bellarmine…

While I do agree with you that 220 seems large, like you said, my team has pulled off entire rebuilds in days. Granted, not great rebuilds(look at the sig), but rebuilds nonetheless. A week and a half, imo, would be more than enough time to tune the flywheel, grease the bearings, tweak the code, etc.

This could probably raise an average score by 40-50 points (not sure, don’t have experience scoring 140+ points per match, then improving).

I’m not saying its not enough time, but there would have to also be time left for school work. 8000A had states, and a scrimmage a week later, so they rebuilt an amazing robot in a day, and practiced driving it around for a scrimmage. So, a week and a half is a lot of time, but I assumed there was school, too.

You guys seemed to have missed the point. This post was about scuffing balls. The OP made it sound like the only way to score into the 200 and 300 point range was to do physical damage to the ball.

I said

I did not say we always score 220 or any such thing, I said WE CAN. For example, we have a standing programming skills score of 143 (and obviously that is only one minute). The only reason I included the scores in my original post was to show that we are not a team that only scores 35 points. The exact number is irrelevant. (though I was not lying, which @Fact Check seemed to be accusing me of) The real point is that you can score high numbers (whatever they may be) and NOT scuff the balls.

Also, just FYI, we have added high lift capability, so +50 points on top of flywheel tuning. We will hopefully be making a reveal video in a few weeks.

I’m sorry if I had misread your comment. Regardless, those scores are pretty good.

Though I was not a referee at that event, as a referee for other events and future events in florida, I would not issue a DQ after the match. There is simply no rule that would be considered match affecting. I would consider barring the robot prior to the match through <r2> part D through <r3> part A, meaning you would have some time to fix the problem. But, I also recall that they warned every team about this issue even before the drivers meeting because the teams I mentor also ran into that problem at the event.

However, as a spectator, I did see that balls that were horribly mangled up. There were some that had so many chunks taken away I thought someone tried making a golf ball. If every robot took 1 chunk every match, combine that with 100 competitors across middle school and high school, combined with about 7-10 matches at states, I would ridicule the quality of game pieces by elimination rounds.

As a Vex U competitor though, I do applaud you for your high scores. The teams I mentor fear you guys. But by now you should realize omni wheels have that risk, especially when I recall that your sister team changed wheels for that event. Other teams have been scoring that same point range without the tiniest scratch because they don’t rely on omni wheels digging into the balls. Instead of fighting the rules, I would surprise everyone again at states with an even better design.

One thing that does bother me was the stiffness of the balls. The only balls that were terribly scuffed were the balls that were super stiff. But still, halfway through the season, we should already be designing around that

I’ve deleted two posts in this thread. One for name calling and one for quoting the name calling. I know everyone is passionate about their robots, but everyone needs to relax before posting.

Thanks Draco, I’m gonna post this to the official thread and see if we can get a read beyond the link I gave before as definitive for State. We aren’t ever taking chunks out of foam, even little ones, but it’s true the omni eventually will take some of the skin off of the ball. When we switch out the launch wheels, it’s for skills.

That’s not what I meant, there are lots of great designs to be seen besides flywheels for those scores.

I’m not trying to be rude, but it really looks like little chunks based on the picture you posted? It was my understanding that the foam on the field in the picture was a result of your robot? Perhaps I’m misunderstanding…

Just to clarify, we use a flywheel. You can score 200+ points with a flywheel and still not scuff balls. We have been through dozens of matches thus far and I still have yet to see any ball residue on the fields.

My main concern about this is that it changes the composition of the ball for other teams. If any particular teams flywheel changes the “skin” of the ball significantly, that could have adverse affects on other teams launching mechanisms which they have to no way to anticipate.

It’s ok, I don’t take it as rude. The specs you see are from the skin on the ball, not the foam. It is a very very thin coating that gets sheered.
My main concern with all of this, is understanding. In the tournaments that we have been to, at least 50%+ of the robots are omni-wheel launchers. This last one was the first time it’s been an issue and it was our fifth competition of the year. Since Karthik mentioned that they expect some damage, I’m hoping to have that defined well for our State competition. Not just for us, but for many bots we’ve seen. I just don’t see it with the present definition, but others see it differently.

We had an issue in Toss Up at states that an improper read of the rules, as confirmed later, caused one of our robots to miss the finals. So it’s just a matter of trying to have all of the info up front.

I think I have a few suggestions for teams using flywheels and wishing to cause minimal damage to balls. You’re flywheel should have a very uniform surface–I’d suggest using the 4-inch high-traction tires ( They provide the necessary traction to launch the balls while not digging into them. If you are wanting to use the 5-inch wheels, remove the tread. The best way to do this is to put the wheel on a lathe and sand it. I know that teams use omni-wheels and the 5-inch wheels because their non-uniform surface grabs the balls well, but wheels with the 4-inch high traction tires work just as well and theoretically make shots more consistent. More uniform surface = more uniform shots. If you are using a single flywheel, make the hood (the piece the ball rolls against) as uniform a surface as possible as well. Another thing that I’ve seen teams doing is using zip-ties to stop tires from “inflating.” If you’re going to do this but don’t want to tear up balls, one thing you can do is drill holes through the sides of the tires and run zip-ties through those holes. This keeps the zip-ties off the surface of your flywheel where they tear up the balls.