How to use uncoupler with point motor successfully?

[Ullswater]

Last night I had a go at getting the Hornby uncoupler (R8244) working with a Hornby point motor (R8243). I've found it very fiddly at it is not working properly at the moment.

 

I've read quite a few threads on this forum and others that suggest it

 

is not the best solution, but I would like to persevere with it.

 

Is anybody using this combination successfully and are there any top tips as to how to make it work properly?

 

I also wondered why Railmaster includes a dwell time for the uncoupler,

 

as this seem to introduce unnecessary pressure on the operator to get the loco moved off once uncoupled. I wondered why not just press the uncoupler icon once for up and again for down?

 

Finally, are there any instructions online that are more detailed

 

than the rather sparse instructions included in the uncoupler unit?

[Rog RJ]

I'm sorry I can't help with getting it working properly but the dwell time needs to be limited because if power is left connected for more than a short time the point motor will overheat and burn out. It's for this reason that passing contact switches,

 

or sprung to centre toggle switches are used to operate points.

[Ullswater]

Thanks Rog - that helps me understand the dwell time.

 

It provokes another question in my mind though - I assume the accessory decoder should continue to be set to drive a point motor (as if it were changing a point), ie with pulses, not to be set

 

to be continuously on (as if it were setting a signal)?

 

I assume Railmaster continues sending pulses for the duration of the dwell time set in the .ini file, to ensure the uncoupler stays raised for that time? And this is something you have to do specifically

 

for the uncoupler because it is working against gravity, whereas a point is not?

[Flashbang]

Hi

I haven't used the R8244 uncoupler, but to me logic says (ha ha I can hear you say - logic!) that the point motor throws from its Normal position with uncoupler lowered to Reverse with a momentary pulse of power and surely the ramp then mechanically

 

remains Up until a second pulse is applied to the point motor to drive it from Reverse back to Normal and the ramp then lowers? No power is need to hold it up in the uncoupling position?

Or have I got it completely wrong and Hornby want point motors burnt

 

out that are holding up uncoupling ramps?

[Bulleidboy]

Could you not use one of the modern slow-motion point motors? The Cob*lt Digit*l can be mounted beneath the board but sideways, therefore the arm would be going up and down, rather left and right.

[Fishmanoz]

The Uncoupler is designed to work with a surface mount point motor mounted next to it. With manual operation, you just throw the point motor to raise it, then throw again to lower it. RM "improves) this by doing both with a single button press initiating

 

both up and down firings, with the dwell time specified in the ini file being the time until it lowers it. So you can adjust the dwell time but not convert it back to manual style operation.

 

Given the intention is that you drive the train over the Uncoupler

 

then back up to make uncoupling possible, it should then be possible to raise the Uncoupler and drive off before the ramp lowers, so completing the operation. If you can't do this, either adjust the ini file dwell time, or rise it again, or both.

 

Seems

 

to me that in general it is a useful feature that saves you having to lower it again.

[Fishmanoz]

There's no suggestion that this is really a point motor fryer with a one off advantage that it can raise an Uncoupler prior to frying. I think it just operates on standard solenoid pulses with RM doing both the up and down pulses from a single command.

 

 

 

I'm sure you could substitute a slow action motor such as bulliedboy suggests. You would have to program the accessory decoder for continuous instead of pulsed output though, just as when driving a point with one of these. And you could use a TT300

 

with inbuilt decoder too.

[Ullswater]

Thanks for the suggestions.

 

I have successfully made the uncoupler work now, with some fiddling. However I have run up against the issue which I know many have which is that even when in the down state, it is too high for some locos. It works perfectly

 

with my Helena Victoria though. I'm thinking about trying to remove some of the height of the uncoupler to get it to work with the other locos, but need to be careful not to take off so much that it won't uncouple!

 

I've increased the dwell time a bit

 

to give me a few more seconds to move the loco.

 

Worth noting that the handheld version of Railmaster does not support the uncoupler just yet - it does show a graphic of it, but tapping on it does nothing. RMS tells me that the next version, which is

 

coming shortly, will sort this out.

[Fishmanoz]

You can solve this right now Ullswater, instead of putting it in you track plan as an uncoupler, put it in as a point. Now it will operate the point motor, and with only one pulse. Now you can raise it to start your uncoupling operation, then lower it

 

again with another command when you are ready.

 

This may even work better for you by the sound of it. All you will have to do is remember that those point lights sitting apparently in the middle of nowhere on your layout are in fact the Uncoupler. Then

 

you can show the Uncoupler too, just don't snap the lights into them, keep them separate.

[Ullswater]

Of course! Brilliant idea. Why didn't I think of that! Thanks.

[Fishmanoz]

Glad to be of service. Cat skinning is flexible in this game.

 

Given your layout in RM is a schematic, you can represent your actual layout any way it suits you. Things like representing 3 way points by 2 two ways. Or using a schematic that looks

 

like a RH point when your actual point is LH. I do this quite a number of places in my layout where I have points inclined at an angle so I use the point graphic that makes the neatest schematic, not the one that is the same handedness as the actual point.