Author Topic: Twin coil switch machines  (Read 761 times)

atsfguy

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Twin coil switch machines
« on: December 03, 2018, 09:32:25 AM »
 Alright, Ihave one for our electronics guys.
I have 15 switch machines from the 1970s that I would like to use on the road I am building. These were made in Watford, England, by Hammant and Morgan. When new, these machines worked very well and I really like them but now I canít get them to function.
I have cleaned and oiled them as the instructions specify but they will not throw. They are AC/DC and I have tried both a trainpack and a 15volt 2 amp power supply off Ebay.
I have wired them per the instructions to no avail. I will greatly appreciate any any and all suggestions, even if it is to discard them. I have worked on them several times, thinking I will eventually find the solutions but finally decided to poll this group for help. BTW, I have an old, new in box Kemtron machine that refuses to operate also.
Thanks for your help.
Cecil
« Last Edit: December 07, 2018, 08:36:53 AM by atsfguy »
Cecil
ATSF-Eastern Division

Alan

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Re: Twin coil switch machines
« Reply #1 on: December 07, 2018, 01:33:05 PM »
I am not familiar whatsoever with the machines you are describing however, that doesn't mean we can't figure it out together.

Can you post several good photos of them so I at least can see them. We can take it from there.
Alan

LK&O Railroad website

When I was a kid... no wait, I still do that. HO, 28x32, double deck, 1969, RailPro

Alan

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Re: Twin coil switch machines
« Reply #2 on: December 08, 2018, 06:54:58 PM »
Cecil, thanks for sending the images. I posted them here so all can see and help you.

sw_mach_1.jpg

sw_mach_2.jpg

sw_mach_3.jpg

sw_mach_4.jpg

These are old twin coil switch machines. Off the top of my head I would suggest:
  • Verify the plunger and over-center mechanism move freely
  • Place an ohm meter on each coil wire pair. If resistance is less than 3 - 4 ohms the coil is shorted and not repairable. If the resistance is infinite the coil is open and not repairable.
  • Lightly abrade and clean the contact points on the blade switch
  • Apply power directly to the coil leads bypassing switching components
Let us know how you make out.
Alan

LK&O Railroad website

When I was a kid... no wait, I still do that. HO, 28x32, double deck, 1969, RailPro

atsfguy

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Re: Twin coil switch machines
« Reply #3 on: December 10, 2018, 07:24:35 AM »
 Thanks, Alan. I tried all your suggestions last week with no success, so into the trash they go. I appreciate your looking into the problem.
Cecil
Cecil
ATSF-Eastern Division

Alan

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Re: Twin coil switch machines
« Reply #4 on: December 10, 2018, 07:32:14 AM »
Probably best anyhow. Solenoid machines are rough on point rails. Much gentler to use geared stall or servo.
Alan

LK&O Railroad website

When I was a kid... no wait, I still do that. HO, 28x32, double deck, 1969, RailPro