I recently installed a Circuitron Snapper CDU. Now, a number of my points “bounce” away from the stock rail when I throw the turnout. I have to pu***he button a second time to snug the points agaist the rail. I’m using Rix switch machines, Atlas Custom Line turnouts, and the Snapper.
Does anyone have a cure for this?
I installed the Snapper because I had some pushbuttons sticking and was tired of replacing switch machines.
Tom
Sounds like too much voltage is hitting the machine or there is no give in your switch linkage. You could try either using a thinner actuator rod to absorb some of the force or add some resistance to the circuit (between the snapper and the switch machines) to cut down on the voltage seen by the solenoid of the rix machines.
Another possibility is to add mechanical resistance to the linkage. This can be accomplished by attaching a tensioned spring to the linkage that will add some friction to the movement. The friction would have the same dampening effect as a shock absorber does to an automobile suspension that keeps the tire from continuing to bounce more than one time after hitting a bump.
A friend of mine had a problem like this on his layout some years ago. It was caused by the switch machines getting too much voltage. He solved the problem by running them from a Lionel AC power supply. That way, he could turn the voltage up or down with the throttle control of the Lionel power supply.
What is the amp and voltage output of the power supply feeding the snapper?
What gauge wires to the switch machines?
Which Rix under table mount are you using? Have you tried adjusting it?
Your problem is the linkage.
ALL twin coil machines need a spring to maintain contact once they’re thrown.
The ‘Snapper’ merely energizes the coil - which moves the slug - and shuts off.
RIX RAX’ have springs. Even Atlas switch machines have springs. Where are yours? (Sounds to me you bought something 2nd hand).
Springs come with the switch machines - OR You can make them.
If you can’t, contact a LHS or RIX. They’re cheap.
HERE the linkage is a piece of spring steel:
That’s what I’m thinking too Don.
Other things need to be checked to be sure they’re operating as they should to eliminate them as possible problems. If the power supply is less than an amp and / or wires are under size, it could be that they’re actually not throwing all the way. Also a stuck button may not allow the snapper to recover, causing a short throw.
The points on a Atlas turnout do not have enough weight, mass or resistance to counter the throw rod to make it bounce away from the stock rail. It’s probably linkage slop, fulcrum out of adjustment or throw rod hitting the side of the clearance hole.
There’s a lot of tweaking required with under table switch machines
Some things I have discovered:
Tom, you could add another capacitor to the snapper so that it takes a little longer to discharge. The capacitor maybe discharged before the machine comes to a stop and that will allow it to bounce out of the stop position. Or you could try making more tension on the linkage. The linkage to the turnout may be to free and allowing the machine to bounce out of the stop position. More tension on the linkage may help lock the machine into the stop position and not allow it to bounce back out.
I believe one or both of those things will fix your problem.
Thanks
Rick Rideout
Rix Products
I have a 25V 2amp power supply feeding the Snapper through 12 gauge wire and 12 gauge wire to the control panels. From the panels to the Rix coils, I’m using 18 gauge wire. Pushbuttons are Kadee Quickee Switches. I have ordered new pushbuttons and will be building new control panels to eliminate the sticking pushbuttons.
All points were making solid contact with the rails prior to installing the Snapper. I can pu***he button and watch the points hit the stock rail and bounce back.
I am using new Rix twin coils without the auxiliary contacts and Rix flat mounts.
My tabletop is 3/4" thick with track mounted directly to the table with no cork roadbed. The Rix flat mounting racks are mounted directly to the bottom of the table. As a test, I mounted some of the mounting racks on a piece of 1X3 to give additional distance (thus additional throw) between the switch machine and the turnout. This seems to be helping.
Some other things I have discovered about the Rix switch machines:
Before installing them, remove the metal slug and file off any burrs both around the outside edge and in the center slot.
Then rub down the slugh and the thro
fiatfan
Regardless, you NEED a spring in the linkage that HOLDS the points to the stock rail.
The RIX RAX 001 and 005 have a long spring steel wire - as part of the linkage - and will cure your problem; or you can wrap some brass wire around a pecil to form a linkage with ‘feet’ to fit the Rix and Atlas throw bars.
I use both RIX’S RAK’S and they do the job, and are adjustable. I also recommend intalling his SPDT contacts to feed frogs. I Never tried grahite to make the slug more slippery. My 15,000 mfd Cap. shoves anything - and the RIX RAX spring doest he rest.
http://www.rixproducts.com/6280001.htm
http://www.rixproducts.com/6280005.htm
YOUR 'Snapper is undoubtedly moving the points, but once discharged, tension disappears and there is nothing to correct he bounce…
That’s weird. The snapper has a huge capacitor and I never would have guessed that it could discharge that quickly unless you were throwing a series of switch machines with one button. Adding another capacitor would be like hitting the button the second time. And what size capacitor does it need?
That may be kind of a Band-Aid solution and not actually curing the problem.
The power supply and wires are more than adequate.
Tom, when you did the test, did you try it without the linkage connected to see if the switch machine bounced?
I think I see what Rick was saying and why it worked before installing the CDU.
Before the CDU, the slug was being held at the stop position a little longer by the magnetic field from holding down the button longer than a capacitor discharging.
But now the switch machine is getting sudden short pulse instead of a longer “on” time, causing the slug to jump and quickly release momentum, allowing it to bounce back.
External springs would cure the bouncing, but I think tightening up the linkage (and/or pivot if possible) and adjusting the fulcrum plate for more throw should be tried first. It’s no cost.
Good luck Tom and let us know what happens.
Ok, what I did after talking to Circuitron was drop the input voltage from 25.3 to 12.6 and evrything seems to be working properly. Thank you Circuitron!
Tom
I dragged this topic back up to see if I could find it in the search. I will edit this after my next test.
Tom
Edit: Even after editing the topic, it will not appear in the search engine. I will try again later and see if the search mechanism simply needs time to index the topic.
Tom