Scalefour Forum

Further discussion of chairs and rail mismatches now at https://www.scalefour.org/forum/viewtopic.php?f=40&t=6083
Rgds

I've given this its own topic as it seemed out of place in 'Construction of a test track' som long after the previous discussion.
The previous mention can be found here https://www.scalefour.org/forum/viewtopic.php?f=9&t=5241&hilit=test+track&start=125#p56043
Regards

One thing no one has asked about is the half red - half green lever. This is "stop shunt" signal - ie it is a shunt signal which is normally "off" to allow shunting, but when the lever is pulled, shunting is stopped. I don't know what colour these should be, so I used red/green....

The M3 series point motors were quite an old design by the 1960s. The new BR spec for point motors came out in the early 60s after which the usual Westinghouse supply was the 'Style 63'. Those cast iron relay boxes did not hold very much, that looks to be a row of 6 boxes, doors to the right, with a...

Difficult to be sure what is going on from that picture, as the relay boxes are hiding the rodding cranks. But the most likely situation is that the point motors are temporarily disconnected with the rodding passing underneath to the point stretcher.
Regards

Yes, with an acknowledgement.
Rgds

My question as a novice is about the mechanical vs electrical operation of the point motors. I have looked online at the wbsframe.mste.co.uk and it is very informative but for the non professional I still can't work out some basics, sorry. Do the Westinghouse (1920s) frames (electric) still have me...

Le Corbusier wrote:
Thanks Keith,

What Thickness of guitar string do you use?

I have a collection from 8 thou to 12 thou, most wagons I think are using 10 with wagon weights around 50g.

The first is to do with the Bill Bedford sprung W irons. The guitar wire threads through the base of the waisted bearing carrier and then is located on either side in a pilot hole in the etch. The wire is not equally straight ... some sections having a slight curvature. This means that when all the...

Knuckles wrote:Explain how this point works!

i take it from the smiley that you know the answer, it doesn't work.
Regards

The diagram is in the tortoise instructions,
See diagrams 2 and 3 on attached.
Rgds

you will need a split DC supply ( ie , +12, -12, 0v )

Yes, and simply obtained from a transformer by using two diodes, abeit more of an issue with switch mode PSUs.

You can certainly operate a tortoise with a single pole switch, eg the microswitch that is intended to be fitted to the frame, so I would expect that to be equally doable with a Cobalt, if there is a problem with the Cobalt design putting a cheap relay in between will sort it.
Regards

Under Rodding it states "It is the correct size to accurately represent 4mm scale point rodding."

Ah, so it does, don't know how I missed that when reading through it.
Regards

Apologies if I've missed it but the data sheet doesn't seem to mention what scale these parts are being produced in. Agreed, it does not seem to say explicitly what scale. Cranks are described as a tiny bit overscale, A-frames as being almost to scale. :) I think that 00 is probably a reasonable as...

I certainly don't see a 1F using more water per mile than Tornado, even given the saturated/superheated difference.
Regards

I now want to renovate my test track and connect it with a new DC controller. As this would be for loco testing only I would prefer pure DC with no feedback or such sophistication Note the original request. Sophisticated devices like Pentrollers/pictrollers don't come anywhere near this requirement...

Why do these not suffer from the same problem of heat build up and solder migration? The heat produced is a result of the power dissipated in the joint W = I 2 R With an RSU the current is much higher than for any normal model railway operating current, potentially well above 10amps So even if the ...

Back in the days of printed templates we used to slit and bend the templates as described here: https://www.scalefour.org/history/protofoursociety/manual/4.1.3-construction-templates (Unfortunately much of the value of these archived docs is lost as the illustrations have been removed). Nowadays I w...

So the questions remain: have I missed something, is there an easier and quicker way to do this - what is the recommended best practice for ballasting ply sleepered track? The protofour manual advised laying track and ballast together and that has always worked well for me. See http://www.norgrove....

Look at http://www.norgrove.me.uk/GWRtracknotes/R4423.pdf
You will see why the Maximum cant is commonly used on tight radius curves, the % increase in speed can be considerable.
Regards

Noel wrote:Wouldn't expansion of the rivet produce compression stresses?

Action and reaction, compression in the rivet has to be resisted by tension in the surrounding metal, otherwise it will distort (or crack).
Regards

Don't use the 'IMG' tag when placing in line, just put the cursor where you want it and click on the place in line button.
Sounds like you had a good day.
Regards

I think Martin is looking for the crank throw, not the crankpin throw. The crank throw is equal to the cylinder stroke, so that should be quoted somewhere. usually on the diagram so the tractive effort can be calculated. Regards PS. just checked Wikipedia, gives 24" stroke. See https://en.wikip...

Most of the needed info on diesel wheels is here http://www.clag.org.uk/wheelbase.html
Regards