View Single Post
  #28   Spotlight this post!  
Unread 15-04-2012, 15:22
Doug G's Avatar
Doug G Doug G is offline
Coach / Teacher
FRC #0701 (Robovikes)
Team Role: Coach
 
Join Date: Dec 2002
Rookie Year: 2001
Location: Fairfield, CA
Posts: 877
Doug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond reputeDoug G has a reputation beyond repute
Re: Do you have to use 2x1x1/8" tubing for a WCD?

Quote:
Originally Posted by billbo911 View Post
I have a simple question about the construction of a "WCD" system. Having no experience with these, yet, we want to learn from other's experience to help minimize the normal error associated with trying something new.

I see mention of using "bearing blocks" quite often when building WCD's. It is necessary? Couldn't the bearing's be pressed directly onto the walls of the tubes?
Hey Bill! This was our first year of doing a WCD. We have been using 1.75" x 0.75" Aluminum C-Channel for so long, we decided to stick with it and use it for a WCD setup. We did two pairs of C-Channel facing inward and milled center bearing holes for 1/2" hex bearings with a 1/8" drop. Then we milled slots on the ends to accomodate either 4" wheels or 6" wheels (4" was used in competition). We made bearing blocks out of chunks of 0.5" x 1.5" aluminum stock. With a tapped hole on the ends, we could then tension the chain easily. The setup worked perfectly and we never once had to touch the drive system.

The downside of our approach of using 4 lengths of C-Channel instead of the classic WCD 2x1 was weight. Our chassis was definitely heavier than most WCDs. BUT we knew this and since our approach to the game this year was to carry another robot on top of us, we decided to play it safe and go with a more robust chassis. Our robot drive system and chassis was tested up to 400 lbs including bridge climbing and balancing.
Attached Thumbnails
Click image for larger version

Name:	DSC_0270.JPG
Views:	114
Size:	81.4 KB
ID:	12613  Click image for larger version

Name:	DSC_0186.JPG
Views:	110
Size:	85.7 KB
ID:	12614  
__________________
Work Hard, Have Fun, Make a Difference!

Reply With Quote