We used a lot of VexPro parts this year.
WCP 3 CIM SS WCD
We used them this year, and absolutely loved them. They were reliable, easy to assemble, and easy to mount and remove from the robot, which we had to do multiple times because of belts. They were light, strong, and in general out of the way of the rest of our robot. The only problem with them is that the flanges for the bearing on the main shaft both face the same way, so if the press fit fails, the shaft moves. So please flip the bearing on the back plate and include spacers the correct length so the flange can go on the outside. We fixed that this year by screwing bolts with washers over the flange on the inside, but for next year that would be a great fix. And, even though its not provisioned for it, there was an easy way to mount E4P encoders using just some 3d printed parts and the cutouts in the plate. The only issue we had was them not showing up until week 4.
1/2 Hex Shaft
Love it. Used it on our drive. Never failed once. 'Nuff said.
4" VersaWheels W & DT
We used both on our robot this year. We used the W's in the center, and DT's on the outsides. We have some mixed feelings about them. They wore down really fast, and we were replacing them once an event. They were noticeably loosing sideways grip the later in the event they got. By the end of Galileo finals, one of our DT's was starting to bubble, and another was cracked down the side where it meets the tread. But when fresh, they had tons of grip.
VersaPlanetaries
We used them for the first time this year, and overall we had a good experience with them. We originally had the 7:1 and 9:1 sets, but then they started cracking, and we moved to the smaller reductions. We had issues a few times with screws coming loose, but mostly we just have to make sure to loctite better. One suggestion is to fix the pricing. Buying the gearbox with 3/8" Hex output is $29.99. Buying the 1/2" Hex shaft is $7.99. So why does the one with the 1/2" hex already installed cost $39.99. It just doesnt make sense, and we actually bought the 3/8 and then installed the 1/2 inch to save the money and get more at the same time. Because we did this, we had the snap ring come off of the practice bot, because we could not get the snap ring in right.
Belts
Ah belts. This year we had 6 CIM's. We used 24t 9mm pulleys with 130t belts. We snapped 6 of them over the course of the year. I heard that next year there is going to be a 27t pulley, and the belts are going to be much stronger, which is why I'm not going to worry too much. But please for the belts publish the torque ratings of the belts so we can do the calculations. We switched to using 18t sprockets and #25 chain at worlds, and had no problem whatsoever with it. But if the belts next year are stronger, and we can get bigger pulleys that will fit a WCD we will go back because we loved the students.
Overall, we liked most of the VexPro stuff we used this year. But I do have some suggestions for improvements.
- Sell the WCP DS with the 3 CIM SS plates. I know they have the exact spacing, so it should be easy. Or sell all the pieces individually so teams can mix and match.
- If you are going to sell something for the season, make sure it is in stock at the beginning, and not at week 4.
- A 27 tooth and a 47 tooth gearset for the WCP SS gearboxes. We wanted 10.5 FPS, but to get that, we had to use 14t pinions, which again showed up really late. with a 27-47 we could have used a 12t and gotten very similar to the same ratio.