Problem with Rix II brackets in N scalegreenspun.com : LUSENET : Wiring for DCC : One Thread
I am wiring an N scale layout with code 55 Peco Code 55 Electrofrog switches, using the Rix bracket and microswitches. I am having a heck of a time adjusting the tension on the microswitches. If the tension is too soft, the microswitch doesn't throw and/or it throws after layout power is turned off when the motor "relaxes" (either way a short). If the tension is robust, I typically have problems getting the mechanical points to throw completely, and end up with rolling stock derailing at the points. The "just right" setting is very hard to hit, and I am also wondering about the reliablity of such a fine adjustment.
I'm guessing this problem is caused by the very short throws in N scale turnouts. For a solution, I am tinkering with the throws a lot, and am also going to look for some microswithces that require very little pressure to trip. I am also considering replacing the Rix/Hankscraft units with Tortise, figuring that the lower current draws in N scale will not fry the Tortise contacts.
Has anyone hit this problem before? Thanks for your help!!
-- Greg Smith (firstname.lastname@example.org), March 06, 2000
I used two micro switches in my HOn3 application. One on/off for each route. It appeared to be rather difficult to perfectly center the 'moment of truth' throw in sync with the movement of the points. I guess I inadvertantly solved the 'relax' problem as well. Adjustment was a breeze because each 'side' was independent with two micro switches. My problems have been narrow wheel sets shorting point to running rail on my clearly unfriendly switches.
-- Dusty Burman (email@example.com), March 29, 2000.
You mention Tortise contacts as your potential drawback. While the contacts are rated at 1 amp, this is a make break rating. The actual contact handling is considerably more and has proven quite safe for normal handling. One would only need to handle the current flow of the track section (turnout frog) or the signal handling that the contacts are controling. In the event of a direct short, current limiting with a tail light bulb would suffice for extra protection. You can also wire the two contacts together in parallel and get extra protection as well. See Don Crano's modifications of Tortise machines for better throw protection with these. The Circuitron folks say they've never had bad contact ruturns.
-- Ed McCamey (firstname.lastname@example.org), April 02, 2000.
Thanks for the answers above and for some who emailed me directly. I would like to comment additionally after having experimented and tried various solutions.
Purchase of "lighter touch" microswitches and very careful adjustment of throw arc appear to have solved the problem. The fix was to adjust the position of the microswitch and plastic stop block on the Rix II so the throw wire was not under so much tension at the end of its travel. The heavy tension I had before was what pushed the motor shaft backward, causing the microswitch to trip when power was shut off.
Having said all that, I will take Ed's advice and go Tortise for the rest of my turnouts.
-- Greg Smith (email@example.com), April 02, 2000.