Mecanum: VEX VS. AndyMark

[yarden.saa]

Hi CD,
I am looking for your experiences with AndyMark and VEX mecanum wheels. I did not use any of them and by looking at the website it's clear that they are different.
Thanks

Yarden

[Ben Wolsieffer]

We have always used 8 in AndyMark wheels, both the old ones and the new type with the outer rollers. The (new) AndyMark wheels are rated for 500 lbs per wheel, so they are nearly indestructible (at least in my experience).

I have never used the VexPro wheels, so I cannot compare their performance, but they definitely aren't as strong. I have seen other teams have their rollers break off during a match. Their benefit is smaller size and weight due to their plastic construction.

[Mike Marandola]

Originally Posted by lopsided98

I have never used the VexPro wheels, so I cannot compare their performance, but they definitely aren't as strong. I have seen other teams have their rollers break off during a match. Their benefit is smaller size and weight due to their plastic construction.

They have since fixed the issue that was causing that.

[Keegbot]

Last season our team switched from 6" AndyMark mecanum to 4" VEX mecanum. This year we are switching back. Our vex wheels lasted for one regional, but once the first one broke, it seemed they broke too often for us to continue to use the drive at off season fundraisers and other events. We got the replacement wheels, and they seem to hold up well, but we have had one break in practice (although it was not the same break). We decided to switch back for this year because the AndyMark wheels never gave us problems.

[Jon Stratis]

We've used AndyMark ones and have never had a problem with them. Our BreakAway robot is still driving with the original AnyMark mecanum wheels, in fact (used as a practice robot, demos, and as part of a programming class at school). We got new ones for our robot last year, and they held up through two regionals, champs, and an offseason event.

[scaryone]

Tried Vex after using AndyMark for years. Lots of broken rollers on Vex. Not sure how redesign will work. Likely sticking with AM

[T^2]

How about neither?

[Electronica1]

My team will give the 4 inch andymark wheels a try once they come in stock. Until then, we will use vex, which will work, but we want to use the andymark wheels due to the fact we have had amazing experience with their 6 inch and 8 inch wheels (they have held up for countless demos and other abuse and still are running great).

[MJ Miller]

I have no experience with Vex mechs, but for AM I recommend the 6"Heavy Duty mechs. These cost $399 per set, have thick side plates, and No 10 screws with bronze bushings - very reliable. The cheaper ones have thin side plates prone to bending, and No 6 screws prone to breaking. I had many rollers come off on the field with the cheap ones. Also, I never have used the 8"and 10" wheels sizes due to weight. Regardless of the wheel size, roller performance is critical to proper drive function (along with wheel contact and balanced robot weight).

MJ

[Jay O'Donnell]

1058 used AM for 2010 and 2011, and used VEX for 2014. I would highly suggest using the AndyMark mecanums. I believe they are slightly heavier, but they (in my experience) strafe better and last longer.

[Mike Marandola]

Originally Posted by T^2

How about neither?

Is there another company that makes mecanum wheels suitable for FRC?

[Ether]

Originally Posted by MJ Miller

roller performance is critical to proper drive function

Quoted for truth. Minimal axial free play and roller spinning friction.

[RoboScout]

Our team has used the AndyMark Heavy Duty 6" mechanum for two of the past three seasons, without a single problem or failure. They are a bit expensive at ~400 for the set, but well worth the additional cost compared to the lighter duty AM wheels or other brands, IMO.

KenSt.

(aka RoboScout)

[Tom Line]

We had an extremely poor experience with last year's (weaker) version of the vex wheels. In fact, after one of our sister teams ran out of replacements we wrapped their wheels with duct tape so they could complete what they needed to because so many of the rollers had broken.

Vex appears to have attempted to address that issue, but I'm always wary of being the test-monkey on an expensive product that goes into a place that is as critical as the drive train is.

On another note, the modifications they've made to the ball shifter has me drooling. I hate dog gears with a passion after this past year.

[Mike Marandola]

Originally Posted by Tom Line

We had an extremely poor experience with last year's (weaker) version of the vex wheels. In fact, after one of our sister teams ran out of replacements we wrapped their wheels with duct tape so they could complete what they needed to because so many of the rollers had broken.

Vex appears to have attempted to address that issue, but I'm always wary of being the test-monkey on an expensive product that goes into a place that is as critical as the drive train is.

On another note, the modifications they've made to the ball shifter has me drooling. I hate dog gears with a passion after this past year.

Just curious, what problems did you have with dog gears?