Hello, our team is considering switching to using the Versa Chassis but as we start thinking about hole placement for the drive base, we have come up with a few questions.
We would like to run an 8WD with 4” wheels and a drop center.
What is the recommended drop distance for wheels of this size?
What is the most efficient way to mount bumpers using the Versa Chassis?
If anyone has any other tips and tricks they would like to share, it would be greatly appreciated!
Thanks for the help!
Assuming you are using VersaBlocks, you will be dropping your wheels 1/8" (as that’s the default drop provided by rotating Versablocks). That should be fine with most wheels, although you may have to pay attention to tread wear on your center wheels.
One of the strongest features of West Coast Drives like the VersaChassis is being able to tailor your wheel size and quantity choices to the particular game challenge. So I’d suggest avoiding picking your wheels before you know what the game is.
We mount ours on aluminum angle extrusion using clip-on barrel nuts, but there are numerous other ways that work.
We have some videos on working with WCD/Versa chassis on our YouTube, and another coming up on the history/advantages of WCD. I will be happy to provide further comments when I have a bit more time.
In the past, we’ve used mainly 1/8, and 1/16 for our drop centers, with wheel sizes varying from 4 to 8 inches. With 1/8 and greater, the wheels are physically above the carpet. With 1/16 and smaller, all wheels contact the carpet, but with differences in pressure allowing the robot to turn.
(1) Beware the bumber support rules. The versachassis pictures that you see at the Vex website do not have anything supporting the bumpers, which is in violatio of the rules.
(2) Bumper Support This is what we do.
On the back of your bumpers, mount some AM-3052 C-Channel. This has an INSIDE width of 1 in. Surround your robot with 1x1 square extrusion. this fits INSIDE the C-Channel. For connectors, use a quick-release pin ( Mcmaster Part # 98320A133 ). Attach your bumpers, drill holes just a little bit bigger than the pin in the appropriate spaces, and then drop your pins in. One warning: Keep track of where your bumpers go – once you drill the holes, keep putting that same bumper back at the same place.