Home made point switches

[RoshamboUK]

Hi all.

I am looking for a very easy to follow 'how to' guide for making home made point switches. I have done a search on the forum for other threads with this content. I now have a basic idea of how the diodes etc work but I am pretty bad with electronics... can anyone point me in the right direction of a step by step guide? I have one of the LGB switch boxes and each switch is running 2 points but It would be nice to switch them individually so im looking for a cheap and cheerful way of doing this. Thanks for the help in advance!!

Chris

 

[Round n Round]

Hi Chris

Take the two wires from the output on the LGB switch box to a Double Pole Change Over Toggle Switch.
The switch will have six contacts, attach the two wires from the LGB switch box to the two center contacts.
Then wire the top two contacts to a point motor. Wire the bottom two contacts to another point motor.
Repeat this four times and you can now operate eight point motors each one on its own.
Method: Select toggle switch to a posistion either up or down and then press the relevent button on your LGB Box.
I operate this on my railway with no problems at all. Hope this makes sense.

 

[RoshamboUK]

Thanks!

A diagram would be fantastic if its not too much trouble. Over time I have been adding extra points, i now have one i would like to operate on its own switch. Is there a quick and easy solution for this? Any diagrams/pictures/tutorials on this subject would be greatly appreciated as I would like to make the points as independent as possible. so even if the LGB box just did 4 points then i had a bank of another 5 'home made' switches separate to do the others. am i making sense or am i starting to confuse myself?

 

[Gizzy]

A much cheaper alternative to the LGB Switch Box, would be to buy the Gaugemaster GM511 A5H toggle switches.

http://www.gaugemaster.com/item_details.asp?code=GM511&style=main&strType=g

http://www.gaugemaster.com/item_details.asp?code=GM511&style=main&strType =

These come with the 2 diodes as well as a diagram explaning how to wire these up, and they can be mounted in a mimic panel....

 

[Round n Round]

I looked into Gaugemaster switches but could not get any sense out of their staff.
As I would have wanted to purchase a large number, I was not going to without suitable advice.
So they lost the sale and I found an alternative.
Like Chris, I already had the LGB switch box.

 

[RoshamboUK]

Cheers guys, 2 very good options. I might just mix and match between the 2 actually. How simple is the diagram that comes with the switch from gaugemaster? ... remembering im not great with electronics. Are the diodes easy to set up and what about supplying power?

 

[Gizzy]

Cheers guys, 2 very good options. I might just mix and match between the 2 actually. How simple is the diagram that comes with the switch from gaugemaster? ... remembering im not great with electronics. Are the diodes easy to set up and what about supplying power?

I found their simple diagram very easy to use. I thought it was very self explanatory how to wire these. I am though, an Electronic Engineer, but I would have thought anyone with some electrical knowledge is capable of wiring these. You will need to be able to solder the wiries and diodes to the switches.

For £3.25, it's a cheap method, and if you don't want the switch having brought one to try, then I will gladly buy it from you.

I have used an 18 V AC LGB supply from a train set that came with a separate LGB controller to provide the power for the points, but I expect that the transformer you already use is an LGB model and it will do the job just as well....

 

[Neil Robinson]

Chris, there's nothing special about 'Gaugemasters' point switches. Any single pole double throw center off sprung to center switch will work. These are often called SPDT (ON)OFF(ON) switches such as Rapid's code 75-0086 http://www.rapidonline.com/sku?tier...itches+-+Salecom&moduleno75284&catref=75-0086 < Link To http://www.rapidonline.co...284&catref=75-0086
The diodes are usually 1N4xxx series such as a 1N4004, Rapid's code 47-3136 http://www.rapidonline.com/sku/Elec...-rectifier-diodes-1N4000-series/66257/47-3136 < Link To http://www.rapidonline.co...0-series/66257/47-3136


Just wire them up as this diagram, the diodes go to the outer switch connections. They are wired in opposite directions to each other. If the point changes in the opposite direction to expected just rotate the switch 180 degrees or swap the wires over at the point motor.

 

[RoshamboUK]

This is all starting to make a little more sense now. I cant seem to put my finger on the right words to search the electronics websites maplin/rapid etc but i would like the 'spring back to the middle' style switch... anyone know the technical word for that? thanks again one and all.... looks like a cheaper solution to throwing points is emerging

 

[ntpntpntp]

This is all starting to make a little more sense now. I cant seem to put my finger on the right words to search the electronics websites maplin/rapid etc but i would like the 'spring back to the middle' style switch... anyone know the technical word for that? thanks again one and all.... looks like a cheaper solution to throwing points is emerging

As Neil wrote earlier, you're looking for what is comonly written as (ON)OFF(ON), the parentheses around the (ON) indicating the the switch doesn't stay locked in that position. Maplin seem to refer to this as "non-locking both ways, centre off" . I've also seem such switches called "centre biased".

If you look at
http://www.maplin.co.uk/Module?ModuleNo=2341

you'll see that Maplin list the different types of switch action as A, B, C etc. For the range of switches on that link above, type D is the (ON)OFF(ON) action that you're looking for, in a SPDT switch. Type H is the same action but for a DPDT switch. So, you'd be looking at item "Sub-Min Toggle D", part number FH03D

 

[Neil Robinson]

I cant seem to put my finger on the right words to search the electronics websites maplin/rapid etc but i would like the 'spring back to the middle' style switch... anyone know the technical word for that?

Try first searching for Miniature toggle switches and then look for SPDT (ON)OFF(ON).
As an example click on the blue link below, you should see 12 switches, one of which fits the description.
http://www.rapidonline.com/Electron...le-switches-Salecom/75284/kw/on+off+on+toggle < Link To http://www.rapidonline.co...84/kw/on+off+on+toggle

Edit, noticed more good advice from nptnptnpt posted whist I was preparing this.

Then again you don't have to use switches at all, there's the 'electric pencil' method. A bit of brass rod forms the pencil which is connected to one side of the power supply with flexible cable. The diodes are connected to brass pins or screws suitably mounted on a track plan or a labeled control panel.

 

[RoshamboUK]

some great advice coming through here. i found this switch

http://www.rapidonline.com/Electron...PDT-Rocker-switch/71452/kw/(ON)OFF(ON)+rocker < Link To http://www.rapidonline.co...N%29OFF%28ON%29+rocker

does is matter that its a DPDT as opposed to an SPDT? I like the look of the rocker switch is all.

 

[Neil Robinson]

A DPDT will be fine, but maybe more expensive than a SPDT equivalent.
You may wish to common the relevant terminals.

 

[RoshamboUK]

i was looking for an SPDT version of that rocker switch style but it doesn't exist. does anyone know if these do exist? Commoning the terminals would be a good idea though.

 

[Neil Robinson]

i was looking for an SPDT version of that rocker switch style but it doesn't exist. does anyone know if these do exist?

They must exist, LGB didn't have them made specially!
Try the link below, the mom is short for momentory which is what you need.
http://uk.farnell.com/arcolectric-switches/c1522ataaa/rocker-switch-mom-off-mom/dp/7674180 < Link To http://uk.farnell.com/arc...mom-off-mom/dp/7674180

 

[ntpntpntp]

Then again you don't have to use switches at all, there's the 'electric pencil' method.

Here's an electric pencil style panel, using Peco studs and probe. I've used this method on my N gauge layouts in the past, but this one's for our garden layout. Actually this one controls the points via a DCC module, but the principle of operation is the same: - you complete the circuit by touching the probe to the studs. It encourages setting the route systematically by "drawing" your path along the line and touching each stud you encounter.

It's a great cheap way of operating points, the only drawback is that sometimes I get the probe's cable tangled with the coily-cables on my DCC throttles! Nowadays I prefer to use miniature push-buttons (where the studs are) rather than stud & probe, but this panel was a quick and cheap lash-up using bits I had to hand, and a box that was a perfect fit for the DCC module .

 

[RoshamboUK]

Thanks Neil that's the kind of thing i was looking for

Nick, that's a really tidy looking panel... Now having seen that I really like it. Don't suppose you have any pictures of the what the wiring looks like just to give me an idea?

Just when i thought i had decided which route to go... hehe oh well!

 

[Neil Robinson]

I hope Nick doesn't my my nicking his image.
I doubt that a photo of his wiring would assist as he is using decoders.
I hope this image helps, all other point motors would be the same with one wire from the transformer common to all and another from each to the common end of the relevant diodes. A pair of diodes can control more than one point motor provided the point motors concerned move together, as, for example, in a crossover.

 

[ntpntpntp]

Nick, that's a really tidy looking panel... Now having seen that I really like it. Don't suppose you have any pictures of the what the wiring looks like just to give me an idea?

Yes I do, but as I said earlier in this particular case the panel is operating the points via a DCC module: specifically a "Mini Panel" by NCE which talks to the rest of the control system over the DCC bus. So the wiring is vastly different than would be for normal analogue operation (well, to be honest there is no direct connection between my panel and my point motors)

In your case you'd be running wires to each point motor as per Neil's diagrams, presumably one common wire and one wire from the panel with two diodes - one diode from each stud for the point.

<edit> Ah yes, Neil's provided a suitable illustration above. Cheers Neil! </edit>

 

[RoshamboUK]

awesome! and what kind of diodes do i need to get? there seems to be about a million to chose from... sorry to keep asking lots of silly questions but I want to make sure I order all the right bits in one go... nothing more annoying than having to do lots of separate orders