Retrofitting frog switching.

[Bufferstop]

How do you go about fitting microswitches to switch polarity as an afterthought without struggling to work above your head whilst under the baseboard, or planting a little hut alongside every point, try the sub-sub-microswitch.

It might look enormous there but the crucial thing is it's only 13mm long and 5mm thick, so if you have any sort of roadbed (cork, ply, foam) under your track you can hide it in the ballast and add the minimum of covering. Then you'll only need short buried wires from frog to switch to rails. I've not a clue what the official description is but I got them from the "Layouts for you" stand at the Gaydon exhibition. £1 each. You can use relatively thin wire keep it as short as possible and a similar gauge to the stiff wire that Peco attaches to the frog these days. Compared to the total resistance of the bus and the rails it won't make much difference and it will be easier to bury. If you are a "modern image" person paint the wire black slip on a length of orange sleeving where it goes under the rails and leave it lying on the surface! Just emulating Networks Rail's practises.

[Mountain]

Any room to mount it to touch the solonoid pin from underneath? Maybe hot glue them to the underside of the point solenoid?

[Suzie]

It is a very effective method, and very easy to get working. Just be a little careful that your microswitch does not have a very strong spring, trying a few different makes may find some that are better in this regard.

[Suzie]

Fitting these types of microswitch to a solenoid can be tricky. The Peco PL15 is a pretty good method of fitting microswitches to a solenoid if you want to go that way.

[Free_at_last]

Any room to mount it to touch the solenoid pin from underneath? Maybe hot glue them to the underside of the point solenoid?

I added an extra switch to some Seep motors using a similar method, also it doesn't put any opposing action on the solenoid.

[Richard08]

Drill a hole such that the switch can be mounted vertically 'in' the baseboard and the end of the tie bar operates it the switch arm? A bit trick to calibrate perhaps.

[RFS]

An alternative, although more costly, would be the Gaugemaster relay switch. It's a DPDT switch so could function for two points in a crossover for example.

https://www.gaugemasterretail.com/magen ... t/?q=GM500

[Bufferstop]

There's actually an even smaller microswitch, but I've yet to find them anywhere but the pages of RS, Farnell and the like. When I worked for the Evil Empire (X***x) they were used in various small sub-assemblies, but even with all their clout you had to change the sub-assembly rather than the tiny switch that was indirectly causing the trouble. I say indirectly because we all knew the source of the problem was contamination leaking from another part of the system.
If the Japanese and their neighbours can produce N gauge track with microswitches built into the track base then it should be possible to produce what looks like a real point(switch) motor for those situations where getting at the underside of points is a problem. I'm looking at ways of fitting them that could be used by those who've relied on point blade switching or have existing sub board switches dying of old age. Microswitches are the way they are because they will fail eventually, so a small standardised package is useful for speeding up repair and adjustment.

Drill a hole such that the switch can be mounted vertically 'in' the baseboard and the end of the tie bar operates it the switch arm? A bit trick to calibrate perhaps.

Calibration should not be too difficult, there's plenty of overtravel each side of the operating point, so positioning shouldn't be critical. Good suggestion.

[Flashbang]

Similar to Bufferstops micro switch, this is from Bitsbox at £0.22p each! Item SW158. https://www.bitsboxuk.com/index.php?mai ... ts_id=2929
These are ideal to use on the opposite side of a point where any make of surface solenoid motors is used - Peco PL11 Hornby R8243 etc where they provide a cheap means of point position switching.

[NickHolliday]

Would these be any good?
https://www.switchelectronics.co.uk/lev ... witch-spdt
Less than 3mm thick if I’ve read the spec correctly.

[Bufferstop]

@ Flashbang' thanks for Bitsbox they are new to me, (now bookmarked) and on the same postal hub which makes a big difference on deliveries. That's what happens when you buy from exhibitions, you pay the price of carting it there, setting up the stall and somebody standing around all day to sell it!

@NickHolliday, Those seem to be a modern equivalent of the even smaller ones I remember. The moulded actuator is probably more efficient than the tiny metal ones of my memory, but you might have to rely on superglue if you want a longer thin actuator.