LNERGE

All we did was behead the old semaphore and plonk a colourlight head on...

I’ve tried several decoders. One headcode panel is alight all the time. The head and tail lamps are fed via the decoder/stay alive. The headcode panel goes out if track power is lost. Any ideas what’s up?

Mr Quick on the uptake here noticed my D9545 was looking rather clean about ten minutes before the Hattons email arrived.

I have one of these.. https://scalescenes.com/product/t037-low-relief-grain-silo/ I think it came in a Hornby Magazine? Very much like the grain facility at Sandy. sort of.. Edit to add… and this is simply perfect… https://www.shapeways.com/product/K8GPY2Q2V/4mm-british-rail-shunting-tractor

It should be a cleaner more efficient magnetic circuit. They look and sound damn good.

Did the yolk across the coils etc make a difference?

Out with the old and in with the new.. and in with the newer still..

Relay contacts are made from silver and silver impregnated carbon so they are near impossible to weld under fault conditions. Plunger contacts can be brass to brass as in the commutator in this token machine. The plunger contacts are brass to brass also but in this case a small disc of brass is riveted into a piece of spring steel.

A diode across the coils will delay the release of the armature.

Here’s the oddball relay.. I’m not suggesting you build one just posting for the fun of it.. This has three coils. Two are in series with the bell line between two signalboxes. The third coil is standing between the two coils and earth. When box A plunges the armature moves one way. When box B plunges it moves the other. One contact will operate a gong. The other a bell. When placed at an intermediate level crossing the keeper can determine the direction of the train from the bell codes etc. This one is going to be installed on a key token circuit over the winter.

That looks magnificent. I’ll try and post something oddball tomorrow that’ll get you thinking. A crazy day today trying to do stuff between trains. A bit calmer tomorrow I hope.

IRSE green book No6 is a good read. It’s quite detailed regarding magnetic circuits. Dead impressed with what you’ve done so far

You’ll find they are opposing each other. Reverse the polarity of one and all should be well. For UAX6 the bell and block together

There is a relay attached to the bell line to the adjacent box. This relay operates the bell. Not required in your case I suspect. The residual gap in your picture looks good.

Freshly taken…

Have a look at this. Better than my ramblings.. The diagrams show the lines of force etc. http://www.samhallas.co.uk/repository/edu_pamphlets/ep_technical_electricity_1_1.pdf

This will complete a magnetic circuit linking both coils. You will need to make sure your armature is not capable to touching the iron cores or it will latch up and stay put regardless of current flowing etc. A residual pin is made from brass or copper in the end of each core stopping the armature touching the iron cores directly is essential. I hope to take some photos tomorrow but it is going to be a busy day.

I wonder what damage was done..

It looks like you have made two coils that are simply acting as electro magnets to attract the armature. I'm in no doubt this will work but some effifiency may be gained by placing a steel yolk between the two cores at the oposite end to the moving armature. You may need to reverse the way the current flows through one of the coils if you try this. There are various adjustments of differing styles available. I can post some pictures if required.

Thank you for the reply. I’m impressed with the stay alive.

Has anyone tried the asymetric brake on these? There is mention that cv27 is decoder automatic stopping. No other mention anywhere else though?

The dynamo i was involved with had three wires. Positive, negative and field?

I ended up fiddling with a Mk1 coach the other day. The fiddling was to do with the dynamo wiring and exposed how little i know on the subject. Travelling from A to B the dynamo will produce DC of one polarity. How does it maintain producing DC of the correct polarity when travelling B to A? I noted the brush assembly moves through 90 degrees between forward and reverse.

An interesting addition to stop the sun shining through the red lense.