Point motors for hand built turnouts.

[down the sdjr]

I am sure this must have been covered before, had a quick look but found nothing.

 

I am starting to lay the track on my new layout and have been looking at point motor options. Liked the idea of working point rodding but may be over complicating things to start with. As the turnouts need a memory position motor due to no spring catch i have been looking at servo types. Tried the Peco Smart Switch, that has a nice motor but i just cant get the frog polarity to work with them. So i have arrived at the DCC Concepts Cobalt IP slow action analogue motor. Has anyone tried these?

https://www.hattons.co.uk/80712/dcc_concepts_dcp_cb1ip_cobalt_ip_slow_action_analogue_point_motor_1/stockdetail.aspx

 

I like the look of them, adjustable throw, frog polarity switching  and will run on a wide range of transformer outputs. Expensive but maybe worth it for all the time and effort i have put into the track so far.

I am interested in what other folk use.

 

Paul.

 

[Phil Parker]

I used Peco point motors with adaptor bases and accessory switches very successfully for many years with PCB track .

[ikcdab]

you dont need cobalts  etc. Ordinary servos do the job just as well. They are equally adjustable and much cheaper.

You need a servo, I use hobbyking hk15178 at £1.90. You need a mount for it. These can be homemade for pennies (loads of YouTube videos). I bought from megapoints at £12 for 12. 

Then you need a driver, again, many around. I have used the megapoints one (very easy to use and excellent) and the MERG servo4 which is a kit to be made up and a little more complicated than megapoints but still very good.

You'll need something to switch the polarity, either a microswitch or a miniature relay. I have done both and I prefer the relays these days. Have a look at my layout blog for more info!

Ian

Edited November 8, 2020 by ikcdab

[down the sdjr]

1 hour ago, Phil Parker said:

I used Peco point motors with adaptor bases and accessory switches very successfully for many years with PCB track .

I am using plastic chairs and 1.6mm plastic timbers, am a bit worried about the peco motors causing damage but i will try one without a CDU as i have quite a few in the spares box.

 

Thanks.

[down the sdjr]

1 hour ago, ikcdab said:

you dont need cobalts  etc. Ordinary servos do the job just as well. They are equally adjustable and much cheaper.

You need a servo, I use hobbyking hk15178 at £1.90. You need a mount for it. These can be homemade for pennies (loads of YouTube videos). I bought from megapoints at £12 for 12. 

Then you need a driver, again, many around. I have used the megapoints one (very easy to use and excellent) and the MERG servo4 which is a kit to be made up and a little more complicated than megapoints but still very good.

You'll need something to switch the polarity, either a microswitch or a miniature relay. I have done both and I prefer the relays these days. Have a look at my layout blog for more info!

Ian

Thank you Ian.

I will have a read of your blog and look at megapoints. I was hoping someone would point me in the direction of a more diy version to save a few quid (have quite a few turnouts to do).

[Andy Reichert]

2 hours ago, down the sdjr said:

I am sure this must have been covered before, had a quick look but found nothing.

 

I am starting to lay the track on my new layout and have been looking at point motor options. Liked the idea of working point rodding but may be over complicating things to start with. As the turnouts need a memory position motor due to no spring catch i have been looking at servo types. Tried the Peco Smart Switch, that has a nice motor but i just cant get the frog polarity to work with them. So i have arrived at the DCC Concepts Cobalt IP slow action analogue motor. Has anyone tried these?

https://www.hattons.co.uk/80712/dcc_concepts_dcp_cb1ip_cobalt_ip_slow_action_analogue_point_motor_1/stockdetail.aspx

 

I like the look of them, adjustable throw, frog polarity switching  and will run on a wide range of transformer outputs. Expensive but maybe worth it for all the time and effort i have put into the track so far.

I am interested in what other folk use.

 

Paul.

 

I'm not sure what you mean by a memory position motor.  Any simple stall motor type will stay at its last position during power off and adopt the position of it's control switch (usually DPDT toggle) on power on. Most stall motors include frog contacts. No electronics required.

 

Andy

[hayfield]

1 hour ago, down the sdjr said:

I am using plastic chairs and 1.6mm plastic timbers, am a bit worried about the peco motors causing damage but i will try one without a CDU as i have quite a few in the spares box.

 

Thanks.

 

If using any type of solenoid motor it is best to put some form of spring between the motor and tiebar . if using the metal bar from beneath swap it for a piece of sprung wire, if from the side use an omega wire. I have not used them but there seems a movement towards servos. Like you its something I have not familiarized myself with yet

[down the sdjr]

58 minutes ago, Andy Reichert said:

I'm not sure what you mean by a memory position motor.  Any simple stall motor type will stay at its last position during power off and adopt the position of it's control switch (usually DPDT toggle) on power on. Most stall motors include frog contacts. No electronics required.

 

Andy

I am sure i have seen a Peco type solenoid stall motor with frog outputs on it somewhere, Hattons Maybe but cant seem to find them anymore.

[down the sdjr]

26 minutes ago, hayfield said:

 

If using any type of solenoid motor it is best to put some form of spring between the motor and tiebar . if using the metal bar from beneath swap it for a piece of sprung wire, if from the side use an omega wire. I have not used them but there seems a movement towards servos. Like you its something I have not familiarized myself with yet

Servos do seem to be the way to go for a beginner like me, but i think i can make something myself. Im going to have a good read over @ikcdab blog before i go any further.

[down the sdjr]

This is how i have been making the tiebars. I use a 1mm strip of copper clad, file the areas i dont want solder on and drill a central hole for the motor pin.I would like to switch from beneath. Excuse the quality i have only recently started making track.

 

[ikcdab]

37 minutes ago, down the sdjr said:

This is how i have been making the tiebars. I use a 1mm strip of copper clad, file the areas i dont want solder on and drill a central hole for the motor pin.I would like to switch from beneath. Excuse the quality i have only recently started making track.

 

That is exactly how I do my tiebars and it works well for me. You will have people saying that the solder joint will fail, and it might if it's thumped over with a solenoid, but servos are so much more gentle and the movement is so small, I don't think it will fail. Mine haven't anyway.

Good looking trackwork by the way. Looks very nicely done.

[ikcdab]

3 hours ago, down the sdjr said:

Thank you Ian.

I will have a read of your blog and look at megapoints. I was hoping someone would point me in the direction of a more diy version to save a few quid (have quite a few turnouts to do).

I thought my solution was DIY! Using servos, relays and a MERG servo4 kit is DIY. 

The MERG kit is around £6 to drive 4 servos. So it's £1.50 per servo. Add the £1.90 servo cost, £1 for a relay and a few pennies for a homemade servo mount means each point is motorised for under £5.

Ian

[down the sdjr]

3 minutes ago, ikcdab said:

I thought my solution was DIY! Using servos, relays and a MERG servo4 kit is DIY. 

The MERG kit is around £6 to drive 4 servos. So it's £1.50 per servo. Add the £1.90 servo cost, £1 for a relay and a few pennies for a homemade servo mount means each point is motorised for under £5.

Ian

Hi Ian, Your advice was the DIY answer i was looking for, sorry my post was not clear. Will be reading your blog in due course.

Thank you.

[hayfield]

2 hours ago, down the sdjr said:

This is how i have been making the tiebars. I use a 1mm strip of copper clad, file the areas i dont want solder on and drill a central hole for the motor pin.I would like to switch from beneath. Excuse the quality i have only recently started making track.

 

 

 

To make the tiebar a little obvious, swap the tiebar for the third timber. I take it one step further buy using brass slide chairs.

 

 I cut the outside part of the chair from the slide plate, the slide plates are soldered to the tiebar The switch blades are then soldered to the plates. The timber is now the tiebar. I finish off by soldering the chair outsides to the stock rails, as the tiebar moves the chairs stay on the rail sides. You can then attach the operating mechanism any way (under, through on top)

 

[down the sdjr]

43 minutes ago, hayfield said:

 

 

To make the tiebar a little obvious, swap the tiebar for the third timber. I take it one step further buy using brass slide chairs.

 

 I cut the outside part of the chair from the slide plate, the slide plates are soldered to the tiebar The switch blades are then soldered to the plates. The timber is now the tiebar. I finish off by soldering the chair outsides to the stock rails, as the tiebar moves the chairs stay on the rail sides. You can then attach the operating mechanism any way (under, through on top)

 

Thats a great solution, really nice.

[AndyID]

9 hours ago, ikcdab said:

Then you need a driver, again, many around. I have used the megapoints one (very easy to use and excellent) and the MERG servo4 which is a kit to be made up and a little more complicated than megapoints but still very good.

You'll need something to switch the polarity, either a microswitch or a miniature relay. I have done both and I prefer the relays these days. Have a look at my layout blog for more info!

Ian

 

Even less expensive is a pulse generator that produces long pulses and short pulses. A changeover switch selects whether the servo gets long pulses or short pulses. One pulse generator like this can control as many servos as you like. I use an Attiny44a (around $1). Code available on request.

 

The snag (if it is a snag) is the servos will all rotate through the same angle (about 90 degrees) so you have to adjust the throw by selecting a hole in the servo's horns and connecting it to the tiebar by something like an omega loop or similar. It's a good idea to do that regardless of how you drive the servos anyway as they can drift a bit over time and due variations in temperature.

 

BTW, another way to achieve the spring effect between the servo and the tiebar is to use a solid connection but mount the servo so that it can rotate against a spring of sorts. That might just be a piece of foam.

[roythebus]

Is it not possible t switch servos from a DPDT switch rather than electronics? I hate electronics with a vengeance! Swirtches are far  easier to understand. Either they work or they dont.

 

[AndyID]

2 hours ago, roythebus said:

Is it not possible t switch servos from a DPDT switch rather than electronics? I hate electronics with a vengeance! Swirtches are far  easier to understand. Either they work or they dont.

 

 

Yes, but you have to rip the electronics out of the servo. I posted how to do it on here somewhere. I'll try to find the link.

 

Andy

 

Here it is https://www.rmweb.co.uk/community/index.php?/topic/96929-no-stall-servo-point-motor-servo-hack/&tab=comments#comment-1812069

 

 

 

 

Edited November 9, 2020 by AndyID
More info

[roythebus]

great stuff. thanks. can't do caps, the cat has come between me and laptop..

[AndyID]

Try pressing the "Cats Lock" key.

[Andy Reichert]

9 hours ago, roythebus said:

Is it not possible t switch servos from a DPDT switch rather than electronics? I hate electronics with a vengeance! Swirtches are far  easier to understand. Either they work or they dont.

 

 

The Mole

7 hours ago, AndyID said:

 

Yes, but you have to rip the electronics out of the servo. I posted how to do it on here somewhere. I'll try to find the link.

 

Andy

 

Here it is https://www.rmweb.co.uk/community/index.php?/topic/96929-no-stall-servo-point-motor-servo-hack/&tab=comments#comment-1812069

 

 

 

 

 

             

 

 

The MOLE and MOLE II, best of both worlds.

 

Andy

[MarkC]

For what it's worth, I have been using H & M point motors on my hand built points for 40+ years, using the built in switch on the motor for switching frog polarity. Always using an Omega loop between motor and tiebar, of course.

 

I suspect that those motors will still be serviceable long after I'm not - they're seemingly indestructible!

 

Mark

[hayfield]

17 minutes ago, MarkC said:

For what it's worth, I have been using H & M point motors on my hand built points for 40+ years, using the built in switch on the motor for switching frog polarity. Always using an Omega loop between motor and tiebar, of course.

 

I suspect that those motors will still be serviceable long after I'm not - they're seemingly indestructible!

 

Mark

 

Mark

 

I still have a box of them and some adaptor switches to double up on top of the units. As you say there are methods of supressing the force of them switching over on the Tiebars. At least you knew when they switched over. The room moves !!

[MarkC]

7 minutes ago, hayfield said:

 

Mark

 

I still have a box of them and some adaptor switches to double up on top of the units. As you say there are methods of supressing the force of them switching over on the Tiebars. At least you knew when they switched over. The room moves !!

And the lights dim 

[AndyID]

Or set off your car alarm

 

I've heard them referred to as "seismic simulators".