Roller Shade Mechanism
Copyright 2007 by James
P. Riser
There are several types of smaller roller shade mechanisms
on the market. Some have a cardboard tube, some have nesting metal
tubes, and others are as shown here. I feel that this is the best
type for modifying for specific custom jobs. This was a car shade
for an automobile window.
The business end of the roller shade has a flat end
running through a nylon bushing that has been inserted into the
end of a split steel tube.
The flat end of the roller shade
core fits into the slot in the end cap so that everything is gripped
securely.
The opposite end is merely a plug that serves as a
bearing for the roller.
Disassembled the mechanism looks
like this.
It consists of the slit metal tube, the freely turning
flat ended shaft, the nylon bushing, and the all important spring.
The spring end is gripped by a
slotted and crimped end on the steel shaft.
The other end of the spring plugs into a reduced area
of the nylon bearing.
This whole inner assembly may be cut down to make it
shorter for smaller roller shades. The problem encountered when
doing so is that the resulting spring tension may be too strong
for the intended use. If the spring is to be cut, do so at the
nylon bearing end and rebend the spring end to fit into the hole
in the nylon. Do not trim off the tapered spring end.
Actually, I prefer to make the complete mechanism on
tiny items. It's a simple mechanism and custom springs may be
used to assure proper strength on the windup action. I use brass
model tubing for the spool (slit on my horizontal milling machine)
and wind the spring from music wire of the required size. Steel
is used for the center rod.