The Massoth Automatic Uncoupler part number 8414002 enables you to raise or lower the hook of an LGB style hook and loop coupler under the control of DCC. You get two uncouplers in each pack.
(I imagine it could be controlled by radio control as well but I have no experience of this. The mechanism is just a servo motor controlled by an open collector running at track voltage, and has the necessary logic inside to control the movement.)
Massoth maintain a list of which locos this uncoupler can be fitted to, easily or with increasing degrees of difficulty. For my first attempt I chose a loco to which the uncoupler can be fitted “as is”, to be specific LGB 21471 Ballenberg rack and pinion steam loco, which comes fitted with an LGB single motor decoder.
The uncoupler is supplied with a 3 lead mini CT plug which fits in various LGB and Massoth boards and decoders. To fit it to the loco you remove the existing hook and loop coupler and replace it with the Massoth Automatic Uncoupler. In order to do this you have to split the uncoupler into two parts, the hook and loop mechanism (which you have to be very careful to keep together, using the plastic band they are supplied with), and the servo motor.
Once the hook and loop mechanism is screwed tightly in place, you fit the servo back on with the two small screws. Make sure the silver nut fitted on the server screw thread fits in the slot of the hook and loop mechanism (see picture). If you don’t the nut will unscrew completely and it is not an easy job to put it back.
Connect the plug to a function output of your decoder and you’re done. Once fitted the automatic uncoupler looks pretty much like a normal hook and loop.
In the case of this particular loco, I drilled a 6mm hole in the bottom of the cab floor under where the firebox goes. This size hole is just big enough to pass the mini CT plug through. Once the firebox is replaced you can’t see the hole.
I threaded the cable behind the firebox circuit board, to keep it out of the way of the motor worm drive, and plugged it into the LGB decoder F1 socket.
Set up your decoder to provide full track voltage to the function output. In my case it was the LGB decoder function output 1 which means CV49 should be value 32. The CV to set the command key for function output 1 is CV51, in my case I set it to F8 (CV51 = 16). With Massoth kit F8 is normally reserved for setting switching/shunting speed on, but the LGB decoder does not support that, so F8 seemed an appropriate key for the uncoupler.
My early experience with using the automatic decoupler is mostly good. Once coupled it seems to be as reliable as a manual hook and loop coupling, and the coupling and uncoupling action is very effective. At first there seemed to be a problem with consistency of the remote control. Pressing F8 first time and the hook lowered slowly, but then it seemed to need to think a bit and I had to press F8 many times before it kicked into life again. The manual says you need 16v to operate the uncoupler reliably. As I normally run my layout at 18v (DC input to command station) the function output is only about 15v once it has been through the DCC signal conversion and the decoder circuitry, so I upped the input voltage to 21v and once I did that there was no problem with reliability. I contacted Massoth about this and they are investigating whether they could reduce the required voltage of the servo. I also asked them if you can connect two automatic uncouplers to one function output (if you wanted one at the front and one at the back) and the answer came back yes you can as they draw very little current.
I found it is better if you couple the automatic uncoupler to a static loop and hook rather than just a loop, better in the sense the connection is not going to part company over R1 points or other obstacles. The Massoth design copes with this very well, by sliding the top half of the loop forwards a few millimetres at the same time as lowering the hoop; this pushes the other coupling away and prevents the other hook from gripping the loop of the automatic uncoupler. The short video clip below shows this in action.
BTW I should say here the Massoth documentation for this product is pretty good, clear instructions and well illustrated. Their wiki used to have instructions for fitting the automatic decoupler to specific locos but their wiki is in a bit of a state at the moment, so if your loco is not on the "easy" list you may want to contact Massoth while they sort out the wiki. Peter TIng and Norbert Rosch who run the Massoth hotline are very helpful in my experience.
(I imagine it could be controlled by radio control as well but I have no experience of this. The mechanism is just a servo motor controlled by an open collector running at track voltage, and has the necessary logic inside to control the movement.)
Massoth maintain a list of which locos this uncoupler can be fitted to, easily or with increasing degrees of difficulty. For my first attempt I chose a loco to which the uncoupler can be fitted “as is”, to be specific LGB 21471 Ballenberg rack and pinion steam loco, which comes fitted with an LGB single motor decoder.
The uncoupler is supplied with a 3 lead mini CT plug which fits in various LGB and Massoth boards and decoders. To fit it to the loco you remove the existing hook and loop coupler and replace it with the Massoth Automatic Uncoupler. In order to do this you have to split the uncoupler into two parts, the hook and loop mechanism (which you have to be very careful to keep together, using the plastic band they are supplied with), and the servo motor.
Once the hook and loop mechanism is screwed tightly in place, you fit the servo back on with the two small screws. Make sure the silver nut fitted on the server screw thread fits in the slot of the hook and loop mechanism (see picture). If you don’t the nut will unscrew completely and it is not an easy job to put it back.
Connect the plug to a function output of your decoder and you’re done. Once fitted the automatic uncoupler looks pretty much like a normal hook and loop.
In the case of this particular loco, I drilled a 6mm hole in the bottom of the cab floor under where the firebox goes. This size hole is just big enough to pass the mini CT plug through. Once the firebox is replaced you can’t see the hole.
I threaded the cable behind the firebox circuit board, to keep it out of the way of the motor worm drive, and plugged it into the LGB decoder F1 socket.
Set up your decoder to provide full track voltage to the function output. In my case it was the LGB decoder function output 1 which means CV49 should be value 32. The CV to set the command key for function output 1 is CV51, in my case I set it to F8 (CV51 = 16). With Massoth kit F8 is normally reserved for setting switching/shunting speed on, but the LGB decoder does not support that, so F8 seemed an appropriate key for the uncoupler.
My early experience with using the automatic decoupler is mostly good. Once coupled it seems to be as reliable as a manual hook and loop coupling, and the coupling and uncoupling action is very effective. At first there seemed to be a problem with consistency of the remote control. Pressing F8 first time and the hook lowered slowly, but then it seemed to need to think a bit and I had to press F8 many times before it kicked into life again. The manual says you need 16v to operate the uncoupler reliably. As I normally run my layout at 18v (DC input to command station) the function output is only about 15v once it has been through the DCC signal conversion and the decoder circuitry, so I upped the input voltage to 21v and once I did that there was no problem with reliability. I contacted Massoth about this and they are investigating whether they could reduce the required voltage of the servo. I also asked them if you can connect two automatic uncouplers to one function output (if you wanted one at the front and one at the back) and the answer came back yes you can as they draw very little current.
I found it is better if you couple the automatic uncoupler to a static loop and hook rather than just a loop, better in the sense the connection is not going to part company over R1 points or other obstacles. The Massoth design copes with this very well, by sliding the top half of the loop forwards a few millimetres at the same time as lowering the hoop; this pushes the other coupling away and prevents the other hook from gripping the loop of the automatic uncoupler. The short video clip below shows this in action.
BTW I should say here the Massoth documentation for this product is pretty good, clear instructions and well illustrated. Their wiki used to have instructions for fitting the automatic decoupler to specific locos but their wiki is in a bit of a state at the moment, so if your loco is not on the "easy" list you may want to contact Massoth while they sort out the wiki. Peter TIng and Norbert Rosch who run the Massoth hotline are very helpful in my experience.
