Opinions on Vex Pro Belt vs Polyurethane Belt (poly belt)

Hey guys, what are some of your thoughts on poly belts vs vex pro belts for internal transport/serializing? We’re trying to get more thoughts on which one’s a better fit for this years game and our bot. Some general pro’s and con’s and/or personal experiences with them would be greatly appreciated. Open to other belt recommendations too!

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May I follow? We have used the orange McMaster belting several times but now have the Vex belt in our possession and would like to know if it’s a good alternative.

My team used Vex belt last year for cargo in an Everybot-style design and it worked perfectly and the weld never failed. Just make sure the compression is good enough.

I heard that some people had to replace a lot of the belts because of stretching issues, did you guys encounter that at all?

No we didn’t. We did wrap the weld with tape for a little bit more security but after removing it, the weld still seemed perfectly fine.

With the wide flat urethane belt, what do you use for pulleys? If purchased… where? If 3d printed do you have a cad file?

From what I’ve seen from first capital ri3d they will wrap it around a crowned roller (e.g. stealth wheels that are bigger in the middle) in order to keep it from slipping to the sides or you can add tape around a hexshaft as a “crown”. Then use a motor to spin whatever shaft is connected to your poly belt. There are some threads here and there on using poly belts that give a way better explanation, so feel free to search “poly belt”. I believe you can get the belt from McMaster.

We use 2.5"x1.25 colson wheels in the past. They are crowned and work great.

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This thread was the most helpful for me.

Do you know how much you overlapped the vex belt before welding? Also there is a glossy and flat side. Is there a difference in which should be on the roller?

About a 1/4" overlap. Spent a lot of time doing it with a candle and stove. Def be easier with a heat gun. I don’t really know the answer to your second question though.

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Did you add compliant wheels on the side? We are using 2" wide belt. The tracking is good without balls, but when we add balls the slightest misalignment generates enough pull move the belt off to the side. We are going to attempt several things. Lessen belt tension, build up crown with friction tape, make spool ends to prevent belt from walking.

For us, we used a crown with a small piece of nylon string wrapped in electrical tape, and it worked flawlessly for us so far. When the belt is pushed off, the crown immediately centers it back to the middle of the crown.

No just the colson wheels. We are using 1" belt and have not had any problems.