June 30, 2011
NEEDS BETTER SUSPENSION - The caboose was built with the axle
bearings mounted in the wheel pedestals with no up-and-down motion.  It
would derail on rough sections of track.  Now its back axle is riding on springs.
FIRST TRY - I removed a pedestal and then trimmed the frame down so there
would be enough travel for the spring assembly.  I started with one spring.  Not
strong enough, so I added a second spring, still not enough, and then stiffer
PEDESTAL AND BEARING ASSEMBLY - The pedestal has been cut to fit
the vertical motion assembly, which consists of the bearing and block which
slide inside a pair of 3/8 channels cut to allow the inside part of the bearing to
ASSEMBLY MOUNTED ON PEDESTAL - The block has been cut to
hold the two springs.  Later I modified it to separate the springs.  The
channels will be secured with screws near the tip of the pedestal (top part in
this view).
READY TO ASSEMBLE - The original springs were #127 from Ace
Hardware.  They weren't stiff enough so these are #128.
ATTACHED TO FRAME - The pedestal and spring assembly has been
attached to the frame. (The springs were straightened out after the photo was
READY TO ROLL - The pedestals have been secured to the frame and 1/2 inch bottom channel screwed onto the frame.  It was not
screwed to the pedestals because it split the plywood; but the idea is to keep the pedestals from bowing outward, so we don't really need it
attached to the pedestals.
The weight of the finished caboose pushes the springs down about halfway, so the axle is always able to float while the caboose rolls down
the track.