pic: West Coast Drive: Spokane Style

[Akash Rastogi]

Originally Posted by squirrel

Cantilevered means the axle is supported at one end or a the center, non-cantilevered the axle is supported on both sides of the wheel.

Thank you very much

[Brandon Holley]

Originally Posted by lilstogi11

Thank you very much

just to clarify a little more for you akash...

If you look at pics of our bot last year that is a good example of non-cantilevered....254/968 are a good example of cantilevered

[Joe Finkel]

I don't think you will climb anything over 20 degr. with bumpers mounts in front of the wheels.

Originally Posted by Joe Finkel

I don't think you will climb anything over 20 degr. with bumpers mounts in front of the wheels.

You're assuming that this is the complete assembly for climbing. It was mentioned that some small changes in the event of climbing being required are easily doable on this design. One gear change per box, and 6 inch wheel instead of 4 inchers. Or, I could leave one side open and put a roller on the front, much akin the 254 during raising the bar (I think theirs was to stop them from rolling over balls, but a few small mods and it would work for ramp climbing).

EDIT: I never sleep.... I need to stop forum lurking....

[jwancura]

ok, so I've been looking at these West Coast drives forever, but I still can't figure out where the bearing blocks for the wheels come from. Are they an off the shelf part you can get from mcmaster by any chance? My team has no milling whatsoever so I'm stuck with finding parts from a store.

[sdcantrell56]

In all of the west coast designs I know of and all of the ones I have designed, the bearing blocks are custom machined parts. There really aren't any good off the shelf parts that I know of to accomplish this. You could always look around for a machine shop to donate some machine time. Many shops are very receptive to robotics stuff. You could also use some of the bearing blocks from team 221 although I don't know if they would work for what you want to do.

[billbo911]

Originally Posted by jwancura

ok, so I've been looking at these West Coast drives forever, but I still can't figure out where the bearing blocks for the wheels come from. Are they an off the shelf part you can get from mcmaster by any chance? My team has no milling whatsoever so I'm stuck with finding parts from a store.

There are options for teams with limited machining capabilities. This link will take you to one option from Robot Market Place.

I am not advising either way with these. There are many more options like these, but it might get you headed in the right direction. A pair of these per axle should do the trick.

[s_forbes]

Originally Posted by jwancura

ok, so I've been looking at these West Coast drives forever, but I still can't figure out where the bearing blocks for the wheels come from. Are they an off the shelf part you can get from mcmaster by any chance? My team has no milling whatsoever so I'm stuck with finding parts from a store.

The best off the shelf bearing block I have found is this one (top of the page) used for front hubs on jr. dragsters. The bearings are a little big, but the assembly looks like it could work for wheel axles. I haven't gotten to play with one... I've only seen them online. They are probably way bigger in real life than they look in the picture.

[AdamHeard]

Originally Posted by jwancura

ok, so I've been looking at these West Coast drives forever, but I still can't figure out where the bearing blocks for the wheels come from. Are they an off the shelf part you can get from mcmaster by any chance? My team has no milling whatsoever so I'm stuck with finding parts from a store.

If your team has no machining resources a West Coast Drive is not a good option. If you have even basic manual mills available, it can be done very easily and simply; but if you don't have that, it will be much more difficult than other possible base designs.

I'd suggest looking into using the KOP frame (it really is awesome) if you have no resources, or try finding some resources. Opening a phonebook/google maps and calling machine shops will surprise you with the results. You'll see that there are both more local shops than you probably think, and more are more willing to help than you probably think.

[EricH]

Adam's right. I just did a quick Google Maps search for "machine shops Kansas City" (noting your location) and came up with quite a few.

[AustinSchuh]

Looks good.

Is there any reason that you have the frame extending in front of the front and back wheels? I know that in the past, one reason for this part has been so that when you ram something, you can't hit it with your wheels. But we now have bumpers, so that isn't necessary. And by removing it, you can move your front wheels up 1 inch, making it easier to climb stuff.

[AdamHeard]

Originally Posted by AustinSchuh

Looks good.

Is there any reason that you have the frame extending in front of the front and back wheels? I know that in the past, one reason for this part has been so that when you ram something, you can't hit it with your wheels. But we now have bumpers, so that isn't necessary. And by removing it, you can move your front wheels up 1 inch, making it easier to climb stuff.

You can also make the bolt tensioners work off of little end plates. This simplifies the machining of cross members as now don't have two holes ~24" apart that have to be relatively accurate.

Originally Posted by AustinSchuh

Looks good.

Is there any reason that you have the frame extending in front of the front and back wheels? I know that in the past, one reason for this part has been so that when you ram something, you can't hit it with your wheels. But we now have bumpers, so that isn't necessary. And by removing it, you can move your front wheels up 1 inch, making it easier to climb stuff.

It makes the mounting of side and front bumpers with a part not yet in CAD much easier. Once I get the bumper mounts finished I'll upload them and you can see why it needs the front chassis extending all the way out. (all four bumpers can be attached and removed with 8 1/4-30 bolts, all vertical facing and easy to access.)

[AdamHeard]

Originally Posted by CraigHickman

It makes the mounting of side and front bumpers with a part not yet in CAD much easier. Once I get the bumper mounts finished I'll upload them and you can see why it needs the front chassis extending all the way out. (all four bumpers can be attached and removed with 8 1/4-30 bolts, all vertical facing and easy to access.)

If you are designing a bumper system that is easy to install and remove, why not use cotter pins?

[EricH]

Originally Posted by AdamHeard

If you are designing a bumper system that is easy to install and remove, why not use cotter pins?

They weren't allowed last year. It had to be a bolt system.