Wheels

[knightmoves]

Yeah - dusty wheels are more prone to skidding. An occasional wipe down with a baby wipe seemed to keep them clean enough.

[brian9640]

A bit of a side note for people who do use Banebots: how do you all keep your wheels clean? Mine tend to get a lot of dust really quickly. Thankfully this hasn't seemed to affect performance significantly (at least last year) but with the aspect of turning this year, I do think it'll be more of an issue.

It definitely impacts performance(made my car run slower somehow idk). Mine would get dirty after every couple runs so during practice, I'd use isopropyl wipes (70%? Can't remember) to wipe every wheel between 3-5 runs. The week leading up to competitions I'd wipe them every 2 runs.

I highly recommend do not use isopropyl or other liquids to clean the wheels at a tournament. Rule 6.i will require approval of the Event Supervisor before isopropyl wipes can be used. Failure to have approval first can result in a competition penalty. The supervisor can prevent the use of these wipes during the competition. While this may seem a very harsh penalty, Rule 6.i is in place to protect school floors. I run Scrambler at a school invitational where I'm required to use only one type of tape. This school is very protective of their gym floor. I would be required at this invitational to protect the gym floor.

Again I recommend not using a liquid to clean wheels. As a good friend said "Do not make an event supervisor think!!!" Anytime a team chooses a method or design that may not be within the rules, you risk the penalties. If you are going to push the rules, make sure the gains are worth the possible penalty.

[pumptato-cat]

Isopropyl wipes will not damage or leave residue on the floor. It doesn't take that long for the wheels to dry, at least not in my experience. Note that I never suggested to wipe wheels during a tournament. I usually wiped the wheels the night before major competitions, but never during.
If you do use them during competition and obtain the ES's approval, wiping before setting up the launcher usually allows the wheels to dry in time. If not, wiping with a towel afterwards doesn't take much time.
As for the "gains" being worth it, I'd say reduced skid and near-perfect braking would be worth the risk. If an ES decided that a student wiping the wheels before the tournament would be worth punishment, they're just a crappy ES. Not sure what else to say on that subject. Either way, I've done this for 4 years and never had an issue.

[Godspeed]

A bit of a side note for people who do use Banebots: how do you all keep your wheels clean? Mine tend to get a lot of dust really quickly. Thankfully this hasn't seemed to affect performance significantly (at least last year) but with the aspect of turning this year, I do think it'll be more of an issue.

It definitely impacts performance(made my car run slower somehow idk). Mine would get dirty after every couple runs so during practice, I'd use isopropyl wipes (70%? Can't remember) to wipe every wheel between 3-5 runs. The week leading up to competitions I'd wipe them every 2 runs.

Ahh alright thank you!! That's really helpful, I'll try something like that.

[brian9640]

Isopropyl wipes will not damage or leave residue on the floor. It doesn't take that long for the wheels to dry, at least not in my experience. Note that I never suggested to wipe wheels during a tournament. I usually wiped the wheels the night before major competitions, but never during.
If you do use them during competition and obtain the ES's approval, wiping before setting up the launcher usually allows the wheels to dry in time. If not, wiping with a towel afterwards doesn't take much time.
As for the "gains" being worth it, I'd say reduced skid and near-perfect braking would be worth the risk. If an ES decided that a student wiping the wheels before the tournament would be worth punishment, they're just a crappy ES. Not sure what else to say on that subject. Either way, I've done this for 4 years and never had an issue.

I'm providing a warning only. It only takes one ES to ruin your day. And yes isopropyl can damage some floors. You idea to use the wipes the night before is very valid. My goal was to point out a rule that most students have not read.

Also there is no advantage of the wipes versus tape. My students have placed top at states and nationals for over 10 years using tape to remove the dirt from the wheels. Tape can be used during the competition to clean the wheels between the 1st and 2nd runs. The wipes either with water or isopropyl used during the competition risk a penalty.

Another item that is not being discussed is team should clean the track before running the vehicle. Just because you cleaned the wheels the night before will not help if the track is dirty. Using a dry swifter to clean the track will help. Especially around where your vehicle will be braking. Remember the students competing before you will be walking on the track and leaving dirt behind. Rule 6.i puts the responsible of cleaning the track on the students.

[Banana2020]

Balloons. They slipped a lot, though. I switched to rubber bands later on but I don't know how useful that'd be at higher speeds. I've also heard of some people using silicon molding or something for the car treads but I don't have a lot of information on that.
My car last year had an average run time of 4.5sec. I guess I gave up speed for accuracy, and I'm not sure if my rubber band/balloon method would hold up at <2.5sec.

Rubber bands definitely work quite well, my average run time this year is around 1.96ish seconds, and the rubber still barely skids with rubber padded wingnut brake(I do use spring but this was when I was testing stuff out). The only issue I have with them is the sheer amount of dust accumulation.

[pumptato-cat]

Oooh, I never experimented with deacceleration(didn't have the time :c) but that sounds very nice. Yeah, I had to wipe the rubber bands a ton, even after cleaning the floor before every practice session. How did you use a spring? I had a lot of ideas to use one last year but wasn't sure how to add it to my design(don't worry! I won't use this information against anyone. Not doing vehicle events any more).

[poonda]

How did you use a spring?

you've probably seen the most popular way before: putting a compression spring between the wingnut and the nut that it stops against
you can also use an extension spring connected to the wingnut to get the same effect without the inconsistency issues from the first method
https://youtu.be/BYeS65N4AQc?t=7 (heres both shown on ladue's 2021 gravity vehicle)

theres a bunch of other ways but those two are the most popular and work pretty well

[stomkins1]

Other options for wheels:
1. Pololu wheels or 3D print and purchase the silicone tire pair: https://www.pololu.com/product/3410 The tires are about 7mm wide and can work on 3D printed wheels up to about 11cm in diameter. I prefer 3D printed wheels so the axle hole diameter can be matched to the axle. Clean with alcohol wipes. These are what the Unphayzed kits use and are quite durable.
2. Silicone Luggage Wheel Protectors on 3D printed wheels. Amazon: $4/8 or Temu $1/8. Not as durable as the Pololu tires, but much wider (13mm) contact area for better traction. The wheels I print are 11mm wide with a 1mm radius on the outer edges; square corners will tear through these tires. Maximum wheel diameter is about 7.6cm. Order extras as you'll probably receive some with defects and they may wear out.