VEX Pro Parts Feedback, 2015

[JesseK]

Now that champs has completed, what were the strengths and areas of improvement for the VEXPro line of COTS products, including WCP? What new products would teams like to see that are in the same core vein as the current VEXPro or WCP products? In what useful or unique ways did you use these products that you wish to share? What nuances or undocumented features did you find with them?

• I really like the WCP clamping bearing blocks + Cams. They went on in no time using a hole saw, and once tuned lasted the entire season with little to no maintenance. They're a bear to get on after powder-coating, but that's a good thing IMO. I plan to come out with a printable encoder mount specifically for this block since we couldn't seem to properly strain relief our encoder wires for them to stay in using the normal WCD methods.
• VEXPro Single Reduction Clamping Gearbox: the King of experimenting with gear ratios in a prototyping environment when combined with a 2nd-stage sprocket reduction. Most intake or lift gearboxes have 2 stages, and this plastic assembly sets up for 2 stages and an encoder very nicely, without needing a chain/belt tensioner. We used it for a lift, but we could have easily used it for a single-speed drive train as well.
• WCP WCD Gearboxes: we experimented with both single and double-speed in the offseason and couldn't be more pleased with how well these work in a WCD setup. It would have been nice to have slower 2-speed options for 6" wheels for the actual season, but we found that we could easily work with what was available. We were very meticulous in initial assembly on the production bot, and only had to perform maintenance on one gearbox one time during the season (the live bearing wanted to come out of the low dog gear, but we re-pressed it using channel-locks and it stayed ... ha).
• Omni Wheels with VersaKey and VersaHub - in a WCD drive setup, we found that we didn't need any bolts to keep the omnis attached to the hubs. The VersaKey matched pattern combined with axle spacers did everything we needed. This was a pleasant discovery.
• BAG Motor - for all of Champs we ran this thing at 80-90% of peak power, and it performed flawlessly. It was put into a brief inadvertent stall once or twice, and still did not burn out. It will be my go-to medium power motor from now on.
• Request: longer belts. The VEXPro belts are very inexpensive 5mm HTD belts, and I'd like to use the 15mm width version for more lifts in the future. Sourcing long belts was tough as many places were out of stock this season. Lifts come in all different lengths, usually with an overlapped portion where two ends of chain/belt meet - so I'd also be happy with purchasing the 15mm belt by the foot/meter.
• Challenge for your Interns: Create a brake mechanism that easily assembles into a gearbox, combines with the Clamping Gearbox, or fits nicely with/on of the other VEXPro products. Bonus points if it fits directly onto a Versaplanetary gearbox or WCP Bearing Block. Holding a game piece steady at a specific height seemed to be a barrier for some teams this season since they didn't realize they needed it until after then entire subsystem was assembled. I never got the chance to redesign ours so it'd take up less space. I'd like to see what you guys came up with.

[Tim Sharp]

The re-design of the 6-inch Mecanums was successful. We ran 1 set all season long and had absolutely no problems at all. The rubber on the rollers will wear out long before the tabs break.

[Dan Petrovic]

I was really impressed with the Versaplanetary gearboxes and especially with how easy it was to swap motors out. We burnt up a few RS-550's this weekend and being able to replace them so easily was huge.

[Conor Ryan]

Overall, I'm impressed by the performance of many parts. I haven't had any issues where I didn't cause the problem. Actually, we won a quality award this year because of our usage of VexPro products.

I'm looking for reasonably priced packages that will help speed up the build season process (basically to take shipping out of the equation). If VexPro had some items that would give teams flexibility in design without having to wait and see, it would be an incredible customer experience. IE - a gearbox speed sampler kit that will give me a variety of speeds I can change in and out or a kit of Versaframe parts that will let me prototype manipulators easily. I'm more concerned about manipulator design than Drivetrain kits.

Website Requests: Give us an indication of how much is left in stock, we might pull the trigger faster.

Design Requests:
Theme: help teams with limited machine capabilities win. I want to be a first round pick with only a band saw, drill press, and a handful of other raw materials.
Linear Actuator, there is a reason why RI3D sold out fast.
Swerve
COTS "Trigger style mechanism" something that could push with a lot of force in a short distance.
COTS Winch.
COTS Clutch
Hex/Key Shaft Couplings
Raw Material Kits.

[Jared]

Our team would really love to see a simple aluminum hex sleeve that's .750 - .500" long or so. We use steel hex sleeves from sdp-si, but these are expensive and heavy. This year, we turned down various aluminum parts with hex shafts in them, including gears, sprockets, pulleys, and the old colson hubs to make our own sleeves, but this seems a little wasteful. The sleeves can be used to couple shafts within gearboxes, or can be used to drive things without hex bores, like McMaster sure grip wheels, with the help of some loctite cylindrical bonding compound.

The versa planetary gearboxes are really awesome, and the aluminum shafts, sprockets, and pulleys are all really strong. The straightness of the hex shaft varies slightly from shaft to shaft, but is generally quite good.

Some of our half inch round (not hex!) bearings were between .498 and .499. We made shafts that press fit into other half inch bearings, including last years half inch bearings, but didn't fit the new bearings. Not a huge deal, but it was unexpected.

Overall, we were really happy with the vex belts, chains, sprockets, and pulleys we used this year.

[wireties]

Love, love, love the VersaPlanetary line. Our (actively-tethered) bot was solely VPs, bags and mini-CIMS. The ability to rapidly change gear ratios and quickly repair motors in the field (that they smoked was my fault) is huge! We also used a bunch of VexPro gussets and extrusions this year, very helpful stuff.

[Adam Freeman]

VEX needs to find a way to make the Versaplanetary gearboxes weigh essentially nothing...

I mean, they are so versitile and easy to use that when you have (10) 2 stage gearboxes, (2) 3 stage gearboxes on your robot, all of a sudden it starts to get pretty heavy or nearly over-weight.

In all seriousness, we used almost exclusively all VEXpro parts for mechanism gearboxes, bearings, shaft collars, and drivetrain components (belts, pulleys, wheels, etc...). I can't even think of what else to ask for...all the products offer such high quality and versitility for a robot designer.

*Edit - We actually ended up not using VEXpro belts for the drivetrain. We had to switch from the 9mm VEXpro belts to 15mm wide, 5mm pitch Kevlar corded belts from Mcmaster (http://www.mcmaster.com/#timing-belts/=wyasp5) because we were skipping and failing them on our practice bot drive system. Forgot about that. We will not be using the 9mm belts or any non-kevlar belts on our drive systems any more. Just doesn't seem worth it to risk failing a belt and an inopertune time of a competition.

Take this with a grain of salt based on where I'm from, but the WCP 32DP gears have to be some of my favorite products so far. They make getting a large reduction in a lightweight and compact packaging simpler and more effective than planetary gearboxes (and in my experiences, more reliable). The seamless integration with pinions for the BAG motor, RS775, and RS550 alongside their perfectly chosen gear sizes (in 20, 40, 60, and 80 teeth) make it so that most any mechanism (especially intakes) can be powered off of one or two stages to get the perfect reduction.

These are a product I haven't seen widely used or known about that I feel would greatly help teams accomplish some of their more complex or weight-dependent design goals.

[sanddrag]

We had several instances of the motor adapters in the Veraaplanetaries slipping on the motor shafts. And yes they were the proper ones, and they were cleaned prior to assembling, properly torqued, and loctite applied.

[Bryce2471]

Originally Posted by Andrew Lawrence

Take this with a grain of salt based on where I'm from, but the WCP 32DP gears have to be some of my favorite products so far. They make getting a large reduction in a lightweight and compact packaging simpler and more effective than planetary gearboxes (and in my experiences, more reliable). The seamless integration with pinions for the BAG motor, RS775, and RS550 alongside their perfectly chosen gear sizes (in 20, 40, 60, and 80 teeth) make it so that most any mechanism (especially intakes) can be powered off of one or two stages to get the perfect reduction.

These are a product I haven't seen widely used or known about that I feel would greatly help teams accomplish some of their more complex or weight-dependent design goals.

I have been hoping that a major FRC supplier would start stocking and selling 32dp gears, for a couple years now. I went the whole season without knowing that WCP was doing it.
Thanks for bringing it up, but it's a little too late, since I just came back from the last competition of my high school FRC career.

[Thad House]

Our robot was essentially a VexPro demo bot. We used the clamping gearboxes, 4 inch mecanums, gears, VPs, hubs, linear elevator kit, and most importantly ThunderHex.

ThunderHex was probably one of the most impressive things I have seen in FRC in a long time. Bearing slop was a thing of the past. Our practice bot used standard hex on the drive, and our comp bot use ThunderHex. The drive on the comp bot was so much smoother it was incredible. We will be using it for years and years to come, especially since it is cheaper then regular hex from Vex.

The 4 inch mecanums were great. We only had 1 break on the practice bot, and it was broken on arrival. I loved them, but I hope we don't have to use them again (I miss my WCD). But if we do, I trust them, and they were very reliable.

The Linear Elevator Kit was great, at least for the plates. We had issues with the 1/2" OD bearings falling apart, so we had to space out our shuttle a bit more, and go to larger bearings for them. But otherwise they were amazing, and very reliable. No problems at all.

The CIM mounts for the VPs were amazing. We used 1 for our Arm, and 1 for our Lift and they both were solid. Figuring out the best way to cut the CIM shaft took a bit of time, but it wasn't too bad.

All in All, I don't think we had a single problem with any Vex parts this season.

If I was going to make a suggestion, The Ball Shifters could use some improvements. I would love to see a ball shifter designed from the start for WCD, maybe even using the WCP style plates. I love the ball shifter idea, but with how weird the mount is, how much space they take up lengthwise, and cantilevering the gearboxes that far is rough, at least in my eyes.

[Michael Hill]

I don't think we could be much happier with their performance. I don't believe we had to change any of our 4" omni wheels at all (no defense does help the situation). We ran belt for the first time this year, and used the HTD from Vex. Those worked out great. We used the calculator on West Coast Products' website (with the added [I think 0.003"] between the centers). Didn't have any ratcheting issues. We drove the versaplanetary with a BAG pretty hard. We had a lead screw mechanism. We fortunately didn't have any issues with the snap ring in the gearbox from placing axial force on it like other teams. We had to change gear ratios several times, so I got pretty good at disassembling and reassembling them. The only issue I seem to remember was having not enough material in the mounting bolt holes. There are only a few thousands of aluminum with threads (Either 8-32 or 10-32, I can't recall). We started seeing wear on the threads and eventually stripped them out and had to get a new mounting block. I was initially critical about including so many extra pieces with the versaplanetary wishing you could configure what you wanted online to save a couple bucks, but we eventually used some of what we initially considered extra parts, so I'm glad for that.

We did burn out one BAG motor, but we were admittedly pushing it way harder than we should have. MiniCIMs were great. We used them for our strafing and they worked out great. We used a couple of gears that worked out fine. Actually, one of the most useful VEX products we used this year were the Delrin hex spacers. We found ourselves using them in situations where we weren't expecting. Having pre-made consistently sized spacers were pretty handy keeping on hand, and I'll recommend we buy more next year. We did use the nylon versahubs for our drive and they worked out fine, but when we used them on our arm, they didn't work out so hot. There was a little too much play that they allowed so we had to take them off. Lesson learned.

[Mike Marandola]

We used VEXpro 6 inch mecanums and tube axle this year, both with success.

6 inch mecanums: The rollers would occasionally bind up due to dirt and dust getting to the bushings, but that wasn't the wheel's fault and we just had to be conscious of this between matches.

1/2" tube axle: We used the tube axle in conjunction with the AM14U2 and 1/4-20s going through to keep everything solid. The only problem was that it wasn't a consistent diameter along the 3 foot piece. The 1/2" flange bearings that we bought from VP wouldn't fit in some spots. This was easily fixed on the lathe and some emery cloth. We are very pleased with it and would use it again.

#ballshiftsohard

[asid61]

Clamping gearboxes worked flawlesly for us. Hex bearings were no problem, WCP bearing blocks, etc all worked fine.
The versaplanetary on our elevator started to fall apart though. The locating pins that kept multiple stages' sides in line with each other and made the whole thing look like a ractangular prism started to fall apart, so the point where we put a hose clamp around the gearbox to stop it from jerking violently every time we moved our elevator. When we opened it up we found that the pin was fine, but the hole it went into had become a slot.

I want 3/8" hex sprockets, or at least versahubs! Why are there no 3/8" hex versahubs!?

[Anupam Goli]

I've gotta say, we've been using VexPro and WCP COTS items more and more lately. We've been on the board with them since 2013, but there were some components that specifically stood out to me this season:

WCP SS gearboxThese gearboxes were really easy to work with. Once we installed them, we just had to spray them with lithium grease maybe once a competition, and that was it. They were easy to use, easy to maintain, and easy to switch motors in and out of. We'll likely be using these guys if we go with WCD-style drivetrains again in the future.

Plastic hex hubs. We used these suckers on our omni wheels. These wheels were live driven and had plenty of weight on them. We didn't have a single one break or cause issues. In a game with actual defense, that may not be the case, but for this year's game, they were cheap and perfect.

There were some things that I'd like to improve, though.

I'm not sure whether it was because of the new Colson mold that included the hub or not, but obtaining Colson Live Hubs this year was kind of a pain. Vex and WCP were out of stock for a majority of the season. Luckily, I remembered that TheRobotSpace existed still, we were able to get the hubs we needed, and quickly (Thanks Clinton Bolinger for the great response time and processing time!). This item may have been more of a niche item now, but 5" and 6" colson wheels still need hubs if we want them live driven.

The only complaint about the Colsons with molded hubs I had was that they seemed to be press-fit for hex shaft, where as the WCP Colson live hubs were loose fit. Sometimes it was a pain to get the smaller colson wheels on and off hex shafts.

It would also be nice to figure out a way to use a CIM or mini-CIM in a VP gearbox without having to cut the shaft down, but that's way easier said than done.