15-11-2006 10:45

Billfred

Re: pic: Colson Wheel and Sporcket.

I'm looking at the wheel, and I'm wondering two things:

1) What exactly got shaved off with the paint can opener?

2) How'd you get the bolt circle done?

15-11-2006 10:52

Chuck Glick

Re: pic: Colson Wheel and Sporcket.

We used "colson-esqe" wheels on our '06 bot. We purchased the NPC Brand from robot marketplace. The NPC brand have a pre-insalled hub (I want to say made of delrin) that is already keyed. So instead of having just the wheel spin, the entire shaft did.

My question is how well does your version work?

15-11-2006 11:54

Gabe

Re: pic: Colson Wheel and Sporcket.

1. A paint can opener has a hooked end, so I sharpened this on a grinding wheel until the edge was like a chisel (think of a paint scraper). Then I mounted the wheel on a bolt and spun it in a drill press and, using the sharpened scraper, started shaving away.

2. For the bolt holes I went online and printed a full size drawing of the kit sprocket, which I glued to the aluminum to show me where I had to cut and file, including where to drill the bolt hole. I used the same method to align the bolt holes on the wheel.

[EDIT]Sorry, Billfred. Misread your first question, but Greg answered it below.[/EDIT]

15-11-2006 13:56

Greg Needel

Re: pic: Colson Wheel and Sporcket.

The colson wheels have a round sidewall, i suspedct the used the scraper like a lathe and flattened out the side wall.

I have used this method before to drill holes, I just would like to issue a warning to people considering doing this. You need to make sure you have a center mark on the holes, then center punch them. Using just the exterior of the hole to line them up can cause issues with proper spacing. Otherwise this is a good solution/use of cad for teams without CNC or machine tools to build parts, It works especially well for sheet metal whole locations and anything that has a flat surface. It can also be used to make cut lines on parts.


I have used colson wheels before for other applications and they are very durable, but the major advantage comes from the weight and price of these wheels, the tread is 65A durometer, similar to the wheel chair wheels.