Foot Drives - Wheel Housing (Pt 2)

So at this point we have the basic frame for the wheel housing. The next logical part of the task is to determine the location for the wheels and drill some holes but before we can do that some work needs to be done on the wheels. I used Colson Performa 5" x 1 1/2" wheels that I found on ebay for a decent price. However instead of using the hubs which came with the wheels, I used some Derlin Keyed Reducer Hubs that I had purchased from NPC Robotics. These reducer hubs work best with the 1/2" keyed shafts which will be used as the axles.

Derlin Reducer Hubs

The hubs themselves were longer than needed so I cut them down to slightly less than 1 1/2". Also, the center area of the wheels were a little wider than the 1 1/2" of the outer part of the wheel and as a result prevented it from fitting in the housing. So I took the dremel with a sanding bit on it and sanded down the area around the hub until the thickness was reduced enough to fit in the housing. After doing that, I installed the reducer hubs.

Wheels sanded down with reducer hubs installed

Next step, determining the location of the wheels in the housing. Based on some advice from other builders, it is recommended that about 1 1/2" of the wheels stick out from the bottom (of the original tube, not the cut line) and that the wheels be far enough away from each other as possible in the housing. I played around with this and eventually found the optimal location and marked them off. I used a 3/4" bimetal hole saw bit and drilled through both sides of the housing to ensure that the holes lined up as close as possible for the axles.

Wheel Housing with axle holes cut

Having the hole saw bit go through and make pilot holes for the other side worked out great. and allowed me to drill the opposite side without much concern as to whether or not they would line up.

Wheel Housing with both sets of holes drilled

Next step was to prepare for the installation of the wheels in the housing. The axle size is 1/2" so I used some  bronze bearings for a 1/2" shaft. The bearings however were a little long so they needed to be cut down to fit with in the walls of the housing without protruding on the inside.  This meant taking the hack saw and cutting 8 of these little things down to size. Not a difficult task but very time consuming.

Full Size Bearing and one cut to size

Once the bearings were cut to size, I used some JB Weld and glued them into place using the axles to ensure that everything is aligned properly.

Fastening the bearings in place

Once that solidified, I did a test fit with the wheels and all looked good.

Test fit with wheels

Next up gears and motors!