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Delayed Delivery – Part 2
Once the basic structure of the gantry is in place, the real task of making the signals signally commences. First up were the smoke deflectors and the brackets for the balance weights. Also fitted are the main portions of the fan route indicator, but that will be explained further once I get it going!
For the arm bearing point and lamps I am using some 3D prints produced by Steve Hewitt and available from Shapeways. They can be found here https://www.shapeways.com/product/JJRSB … arketplace. They are fairly expensive but they are neat and save a lot of manufacture. There is, however, a but – they are very delicate and I am very fearful of thier long term durability. I am highly likely to draw some of my own up and get them cast in lost wax. It will make them even more expensive but I have about a 50% casualty rate at the moment, so maybe in the long term it will be cheaper!
The arms are Masokits, these are definitely the best available arms for LMS/LNER/BR semaphores. This is especially true of the minature shunt arms as the MSE ones are simply too delicate to bother with (imagine how do I know that………….!). So this is where we are now at with the arms mounted temporarly on the bearings.
There are five movements in the down direction (three of which operate via the route indicator) and then a pair in the up direction – hence the back to front arms.
The plates at the top of the dolls are mounting points for ladders. It transpires they are wrong and have already gone!
So the intensity level has dialled up a notch with these portions (especially breaking the bearing/lamp fittings) but it really gets interesting when you try and make these things work.
I don’t know myself yet (although I know for the couple of arms I have finished, so I have an inkling), but i think it might be fun to have a little sweepstake on how many moving parts there will be in the finished gantry. Five arms, three fan route indicators and each is operated by way of angle cranks. Each arm, crank and intermediate wire counts as a moving part, as do the servos………………..guesses please?
Delayed Delivery – part 1
After a long pause, caused by that irratating thing called life getting in the way, I am looking to deliver on some long made modelling promises over the holiday season.
The major task is a rather full on gantry signal with no less than eight movements on it (which is an improvement, when initially designed it had nine!), including a rather natty fan route indicator. This is for a friend’s layout and is in return for some signal cabins that he built no less than 15 years ago – I told you the promises were long made! Mind you, he hasn’t got the layout fully running yet, so I am still ahead of him!
The gantry spans only two lines so it can be formed with channel section. There are good drawings and pictures in LMS Journal no 5 of this. I have made mine from milled brass section and then the landing was a custom etch I designed as it takes a surprisingly large amount of material and effort to construct this from scratch. These etches included the doll base plates although the dolls have a thickened tube at the lower level which of course I forgot and had to undo later work to put on!!
The signal is to be located on an embankment which meant that I could not simply put flat base plates on the foot of the gantry columns. Instead I have constructed a housing that matches the slope of the embankment and then the baseplates are partially sloped to match this with square sections representing the foundations of the prototype columns. Below these baseplates I have then formed housings to take the servos which will eventually operate the arm actions.
So far, this is pretty easy modelling (although I lost a number of drill bits opening up the stanchion positions on the landing – grrrrrr!). The tough bit comes next……………
There are potentially two viewers of this thread who might be thinking that I have long outstanding modelling promises to them too……………I am also working on one of these too!!
highland miscellany 