Point Isolation in Analogue (DC)

[JimmyB]

Having modeled in other gauges, most points are self isolating, in effect power to each branch from the point is made automatically according to how the point is switched, this meaning that sidings etc. do not require additional isolation. Beginners in G are not always aware that power is continuous to both branches at all times when they start, but soon adapt to this methodology. However I have thinking (maybe not a good idea) but if the connections under the point were removed "as required" then the point would not need the track isolation and power could be fed via a switch, not quite the same as other gauges, but would this work?

 

[PhilP]

Having modeled in other gauges, most points are self isolating, in effect power to each branch from the point is made automatically according to how the point is switched, this meaning that sidings etc. do not require additional isolation. Beginners in G are not always aware that power is continuous to both branches at all times when they start, but soon adapt to this methodology. However I have thinking (maybe not a good idea) but if the connections under the point were removed "as required" then the point would not need the track isolation and power could be fed via a switch, not quite the same as other gauges, but would this work?

Yes, it should do...

You will be responsible for power-continuity, and this might be 'interesting' in the garden..
Could use auxiliary switches on the point-motors. - Chris posted about self-latching relays, which would be good for this??

To my mind:
1. Leave points 'as is'. - You may change your mind / go digital / want to sell-on (you will get more for a 'standard' point).
2. It adds a complexity, which some may find a challenge.
3. More joints / connections. - More points (no pun) of failure..
4. The Massoth insulated joiners: These both clamp the rail, and allow an easy connection-point to be made.. Also, allow removal of a point for maintenance, more easily.

YMMV, of course..

 

[Gizzy]

You could cut the linking bus bars under the point and use a switch, but I found it far easier in my DC days to use the yellow (or black) isolation joiners.

I referred to the yellow ones when stabling a train or loco. You could easily see where your isolated section of track was at a glance....

 

[PhilP]

I referred to the yellow ones when stabling a train or loco. You could easily see where your isolated section of track was at a glance....

they also make a pretty good guide as a 'fouling point indicator'..

 

[beavercreek]

USA Trains and Aristocraft's HUGE No6 points (turnouts) have a very long metal frog and so have a microswitch which sets the polarity of the frog depending on the direction of the point. The switch is under the point itself and very vulnerable and tended to corrode if not given some pretty good protection.
When they are working (with a protected microswitch), they work very well and even short wheelbase single bogie diesels pass over completely fine.
I love them, as the radius is so gentle..... BUT they are humongous!

 

[Rhinochugger]

Having modeled in other gauges, most points are self isolating, in effect power to each branch from the point is made automatically according to how the point is switched, this meaning that sidings etc. do not require additional isolation. Beginners in G are not always aware that power is continuous to both branches at all times when they start, but soon adapt to this methodology. However I have thinking (maybe not a good idea) but if the connections under the point were removed "as required" then the point would not need the track isolation and power could be fed via a switch, not quite the same as other gauges, but would this work?

Yes and no, minister.

Yes, it will work, but the drawback is that you then have to keep the rail sides and point blades clean and de-oxidised to keep the contact and current running.

I tripped over this aspect of things in the same way that you have, but on balance, I think the 'as manufactured' method is slightly preferable.

Having said that, I carefully doctored my new #6 turnout to do exactly what you are suggesting - however, it is basically a short spur for setting locos on the rails, and I only butchered the contacts for the spur, not the main running line. I can always use a quick jump lead to the spur if I need to, 'cos being DC, I can only run the one loco at any one time

 

[playmofire]

Yes and no, minister.

Yes, it will work, but the drawback is that you then have to keep the rail sides and point blades clean and de-oxidised to keep the contact and current running.

I tripped over this aspect of things in the same way that you have, but on balance, I think the 'as manufactured' method is slightly preferable.

Having said that, I carefully doctored my new #6 turnout to do exactly what you are suggesting - however, it is basically a short spur for setting locos on the rails, and I only butchered the contacts for the spur, not the main running line. I can always use a quick jump lead to the spur if I need to, 'cos being DC, I can only run the one loco at any one time

Ah, yes, the simple joys of DC, long may they reign.

 

[Greg Elmassian]

In the US, when the power on the diverging track is controlled by the position of the switch/turnout/points we call it a "power routing" turnout.

With the rise of DCC, this seems to be less and less common.

Power always flowing through the turnout help beginners, but it does indeed miss the simple advantage of controlling power by switch position. But since this is really only a benefit in DC only, it seems to be less and less common.

Greg

 

[chris m01]

In the US, when the power on the diverging track is controlled by the position of the switch/turnout/points we call it a "power routing" turnout.

In the UK we call it normal, or maybe just take it for granted when using standard Peco track. G is the odd one out for us compared to all the smaller scales.

 

[ntpntpntp]

In the UK we call it normal, or maybe just take it for granted when using standard Peco track.

Except of course Peco now seem to have embarked on moving over to their "DCC friendly" Unifrog design which (in the recent N gauge examples at least) are NOT power-routing out-of-the-box. Already they are confusing less experienced folk on the N gauge forum I frequent. It's not even a simple case of cutting a couple of bonding wires to make the points power-routing, due to the way Peco have arranged the bonding connections.

 

[JimmyB]

Wow - thank you for the responses, plenty of "food for thought"!!

 

[Greg Elmassian]

In the UK we call it normal, or maybe just take it for granted when using standard Peco track. G is the odd one out for us compared to all the smaller scales.

Funny, wouid have thought the reference for G scale was LGB. which is NOT power routing.

 

[dunnyrail]

I would go with the concensus of leaving the point wiring alone. In fact I would go even further to suggest that you double up on all the wiring as the sliders (also effected by dirt), screws and even riveted connections can fail over time. I know this to be so as I have had LGB Points for over 20 years in the Garden now. I have no doubt that others will say they have had LGB in the Garden for longer than this, but I am recounting my experience.

Finally to isolate your sidings the LGB 1015U short Track Sections (I still have 4 of these advertised for sale) can have a Micro Switch mounted in a Sleeper as shown on this short piece of LGB Track with an Isolator. The odd bit of rail or any short length was my original chosen option but my friend started using the 1015's and it seams a neater option as no soldering of rail is involved.

 

[ge_rik]

Non isolating points was the main reason I went over from DC to DCC (and now battery rc). I figured that isolating the passing loops and sidings was going to make the wiring far too complicated for realistic running on DC. Jon's isolating tracks look like a good halfway house solution, but being able to do all the controlling from the handset is more appealing to my mind.

Rik

 

[ntpntpntp]

I wired my line "DC style" with switchable sections in sidings and passing loops. The switchgear was mounted on a wall in weatherproof boxes.

When running DCC I just switched all sections on. Best of both worlds, especially when visiting locos were not DCC in which case just needed to swap the controller connections and have an analogue day!

Even under DCC I still found the section switches useful when setting out a loco on the track, isolate that bit to avoid any accidental wheel shorts stopping the rest of the system.