Model Forum / General / Railroads / October 2008

David Nebenzahl <nobody@but.us.chickens> wrote in news:490642f2$0$5792
$822641b3@news.adtechcomputers.com:

Somewhere around 1/16" to 2/16", I think.  Some slide switches (electrical)
have a similar range movement, so they work as power-routing ground throws.  
(I did it once as proof of concept, and the throw of the switch was more
than the points, so it held the point rails too tight against the stock
rails.)

Puckdropper

The important thing more than absolute throw is that the mechanism to throw
the points is flexible enough to take up any differences between the various
turnouts you have.  Commercial turnouts do tend to be fairly decent for
throw between various units on the order of 0.003" or so, not all that
important if you are not depending upon the contact of the points to the
stock rail for power to the point rails as that small distance won't pick at
flanges.
However, with homemade/handlaid turnouts or a mixture of turnout makers a
compliant mechanism is a lot better as it allows for an automatic adjustment
for each side of the throw to be fully thrown to the stock rails.
I like a mechanism where a wire goes up under the throwbar and flops back
and forth under the throwbar.  The bar is retained by a tube at right angles
to the section going up through the roadbed.  The tube is aligned in the
direction of the track and is generally soldered on a backing/mounting
plate.  The other end of the tube the wire is again bent at a right angle
and the switch machine pushes that back and forth to move the throwbar.  Use
1/32" wire and there is a lot of flexibility in the wire so that the points
are fully pushed against the stock rails without driving the rails out of
alignment.

--
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
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