Wednesday 28 February 2018

Connecting the Ground Frame

Tuesday 27th Feb

Six of us in action at Broadway today to complete the installation of the southern turnout  ground frame.
Firstly this involves mounting the facing point lock mechanism to a  steel plate, itself fixed to the centre of a wooden sleeper. However, we are delayed from starting by the arrival of the ballast train and we have to leave the points clipped until they have finished their ballasting run through platform 1.


So, to start we mount a slotted stretcher bar so that the FPL casting position can be determined and the bolt hole positions marked:


Note that the stretcher bar and central section of the steel plate are insulated from the rail to maintain track circuit integrity. The blue plastic tube is cut to length and inserted round the bolt with a plastic washer under the nut


Then the mounting holes are drilled - luckily we are able to use the magnetic drill here. Because we are out of range of an electricity supply we brought a generator with us  (not just to boil the kettle you understand!) :

The slot in the stretcher bar was not wide enough to accommodate the locking bar so a bit of in-situ cutting and filing was required:


Len W carrying out the final adjustment with a file:


And finally here's this part of the assembly complete:


Next we turn our attention to mounting an angle crank to the third  sleeper further south. This will connect the locking bar to the lineside crank already installed (this will be more obvious from the shot of the overall layout which will follow shortly)

The fixing of these fittings is a little fiddly as we use screwed rod which needs a nut put on from underneath the sleeper, so a bit of ballast shovelling is required:


And then using the crank base to spot and drill the four moumting holes:


And then mounted in position with its two connecting links:


Having got all the main components in position we were then able to measure and cut the lengths of point rodding to connect everything together:

Sorry about my shadow!
And for the grand finale- here is everything connected up:



While all this was going on Jim P and Len W headed back to platform 1 to fit and bolt down all the pulley wheels required to direct the signal wires north and south - this is now a full set for platform 1 side. Luckily the plate has remained clear of ballast.


On the opposite side, a triple set of pulley wheels has been mounted on a raised bracket - all fittings for signal wires and point rodding at the signal box are now complete and await the task of connecting up to all points north and south!


The new spring hand lever to operate the Headshunt points at Broadway North has been delivered - this wasn't fitted today as a modified connection coupling is required - got to save something for next week!


Bit cold today with intermittent snow flurries, but another good box ticked.

Curly

10 comments:

  1. Well done on job that is not much fun in this cold weather.
    Regards, Paul.

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  2. Just curious as to why you are putting in GF levers. I know the signal box isn't going to be fully operational for a while yet, but wouldn't it have made more sense to connect the points to the lever frame and operate from the box? The S&CR in Swindon doesn't have operating signals yet but their running line points at both main stations are still controlled from the SB lever frame.

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    1. I think the answer would be TIME ! The rodding rollers take time to be set in their correct locations and time is running out as the opening date would arrive and see maybe one point connected to the box by rodding. Hope that helps.
      Regards, Paul.

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    2. Yes, many weeks of work to install and align the rodding stools, etc and we will be running trains over these points in 3 weeks time. Most of the installation we have done today will stay as it is when we connect to the SB- just the ground frame will be removed.

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  3. Thanks for the detailed pictures. I think I understand a bit more now about FPL. I notice there is only one slot in the stretcher so the locking only occurs for one position of the switch. Could you not have a second slot so that both positions could be protected? Or is this not necessary? (Probably showing my ignorance here...)

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    1. It looks as if the intention is for passenger trains to only arrive in Platform 1, using Platform 2 for the loco to run-round. As a result there's no need for the FPL to lock the points for the route to Platform 2 at this stage as they will only be used in the trailing direction for that route.

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    2. Ah yes, makes perfect sense. Thanks for the explanation.

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  4. Will the signal box still be manned on the official opening day and over Easter? would be nice to hear the bell signal tinging away!
    Regards
    Paul & Marion

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  5. I don't think so - nothing is connected yet.

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