Chief Delphi - VEX Pro Parts Feedback, 2015

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Re: VEX Pro Parts Feedback, 2015

Experience with VP items this year

The Versaframe and Clamping Gearboxes were great. We used it heavily for prototyping. We made the call early in the season to go mecanum, and we had a mecanum drive base with versaframe and clamping gearboxes by the end of week 1, which allowed the programmers to have polished drive code with gyro and accelerometer feedback before the competition base was even built.

Speaking of Mecanum Wheels, we had no failures of the 6" mecanums through 88 matches this season.

The Thunderhex was fantastic. We used it for two long shafts that spanned the width of the robot and the rounded corners made a HUGE difference in being able to actually install and maintain the systems. Last year we had a similar long shaft with multiple items pivoting off of it, and we ended up having to chop it into 3 pieces and connect it with massive shaft couplers to enable us to assemble/disassemble the pivot at competition.

Versaplanetaries gave us no issues this year, although we avoided the 100:1 reduction using 2x 10:1 combination that gave us problems last year and opted for the stronger 5:1-5:1-4:1 mix.

Desireables for the future

Quote:

Originally Posted by IceStorm (Post 1478338)

Would love to see a 3/8 hex bore sprocket line come out for #25 chain. 1/2 hex is great but a lot of applications don't need a shaft that thick.

I will also add my voice that a 3/8" hex bore hubbed sprocket would be great. 1983 ended up buying steel #25 sprockets from McMaster and broaching them ourselves for our drivetrain this year.

The colsons look great, I didn't use them personally this year, but I did find myself wanting bearing bore versakeyed versions when I was playing with drivetrain designs pre-season and now again post-season. At the very least, bearing bore with the 1.875" bolt pattern would be nice for dead axle use. I find myself wanting to use colsons where I can put Versawheel DT's for the grip or wear characteristics. With how wide the colsons are, I find that it becomes nearly impossible to nicely package a dead-axle setup with a vexpro sprocket or gear once a hub is pressed in.

Re: VEX Pro Parts Feedback, 2015

Quote:

Originally Posted by mman1506 (Post 1478519)

I wonder if a dual ball bearing supported VP output option would be useful for teams. Pretty much every VP failure I've seen is from excessive combined loads and VPs are just one of those things that teams tend to abuse. Most industrial planetaries of similar size like the Neugart PLE series are dual ball-bearing supported from the factory.

They are dual 15mm ID deep groove ball bearing supported on the output shaft.

The weak spot in the VP output is the snap ring holding the output shaft in place. For most loading conditions this usually doesn't matter, but with pull out loads generated by lead screws the snap ring can fail due to pull out.

The Industrial versions of these type of gearboxes all have the last stage of the planet carrier integrated into the output shaft so they do not have this same failure mode.

Re: VEX Pro Parts Feedback, 2015

Used too many VexPro products to count this year, especially bearings and gears, and I can't think of a one that failed.

My only need this year that wasn't available was a longer hex shaft option for a VP...perhaps an extra-long ThunderHex version?