Tamiya M4 Sherman Project
Page 2: Building the Suspension
The build starts with the main hull structure which is a piece of bent,
formed, drilled, and tapped aluminum sheet metal (1mm). The
picture on the right shows the main road wheel support brackets
installed. These appear to be aluminum castings. The idler
bracket is also metal, but the idler wheels are plastic. These
parts appear to be common to the original 58001 Sherman, but unlike that
model they come pre-assembled here. I assume that is to avoid
getting glue into the bearings when installing the metal hub cap which
would have been a real danger building the original.
Here is some very specialized hardware that can't be easily replaced
with a bolt from the local hardware store. These stepped, threaded
steel axles with flats support the road wheels. An exploded view
and completed assembly are shown on the right. The kit uses bronze
bushings rather than bearings in most locations which is probably fine
for something that will not move around that much. You would need
many dozens of bearings to do a conversion. The axle shafts pass
through the hull and are secured with nuts.
Here is a selection (left) of the two sizes of return rollers
with the bushings installed. On the right you can see these added
to the hull. Note that I've also added the rubber wheels to the
idlers. The road wheels will also get rubber tires, but the return
rollers just get painted to look like rubber on the outer rim.
Here is the pile of parts (left) which make up the simulated horizontal
volute suspension. There are no real volute springs in the model,
instead there are regular coil springs which sit inside cylindrical
cans. These do a pretty good job of looking like volutes.
The metal dampers on the far left are just for show; they offer no
damping on the model. On the right you can see how the six
suspension trucks are assembled (exploded view far lower right).
Each truck has four wheels assembled in pairs attached to arms which
pivot on the gudgeons attached to the hull.
These pictures show the completed suspension. Each truck can
rotate as a unit pushing one wheel pair up while another comes down
without any shock compression at all. If both wheel pairs attached
to a truck are pushed up at the same time then the spring and damper
compress. The little boxes attached to each damper probably
simulate fluid reservoirs.
©2021 Eric Albrecht
