Garden Railway Forum

Great project.

Made me think of the German Huntebrücke:

https://www.nielslehmkuhl.de/bahnlog/di ... -oldenburg

Scrat wrote: Sat Sep 12, 2026 7:37 am Great project.

Made me think of the German Huntebrücke:

https://www.nielslehmkuhl.de/bahnlog/di ... -oldenburg

Wow - that is some bridge!

Peter Butler wrote: Fri Sep 11, 2026 8:14 pm My first thought was of the Bascule rail bridge crossing the Towy in Carmarthen.

Me too - I think about modelling it every time I go over it (so quite often!)

While I am waiting for fixings and materials to arrive I have been carrying out some modifications on the railway. In this case fine tuning pointwork. I have been in the habit of making tie bars from brass rod, and drilling holes in the rails for them to pass through. Like this:
I like the way that this stops the point blades from moving out of position. However it hasn't worked very well on the double slip. Locos are passing through it without derailing, but it was difficult to get all the holes in the blades lined up properly. The end result was that the various blades were not all pressed firmly against the rails.

So I have remade the tie bars out of square section brass, soldered brackets to the blades and drilled tapped and bolted the blades to the tie bar one at a time, ensuring that they are all firmly pressed against the running rails. Like this:
While doing this I realised that a hole through tie bar at the end opposite to where the point lever is mounted would allow me to fit the point indicators I was playing with 18 months ago.

So that led me back to the point indicators!

I didn't get them to work last time I tried, and decided that the mechanism needed to operate very freely for them to have and chance of moving prototypically with the point blades. Two new point indicators:
Part of the problem was that the arm was moving about on its pivot shaft. I fixed that using brass rod 2mm square, and giving both the crank and the arm matching square holes. I drilled some round brass bar with a 2.8mm drill, and parting off short sections to make the bearings for that square shaft. Perhaps not a conventional engineering solution, but it works. I have also made new arms, using blue and white filament - and avoided having to paint the white stripe on.

Trevor

This afternoon I managed to fit the indicators to the point. It is temporarily held down with a brick, to test the throw:
Normally the indication would be hidden in the column (pointing down) for straight on, and to one side to show the other option. In this case there isn't really a "straight on" so the indicator shows to the left or to the right of the column. So in the above photo the point is set to take trains on the left hand track. Here is the point set in the other direction:
The indicator is showing that it is set for the right hand track.

So they work, and the throw of the indicator matches the throw of the point. This matters to make sure that the point blades are not prevented from sitting hard against the running rails.

Perhaps these are really pointless additions, but on the other hand I can now see which way the point is set from a distance. However interpreting the indication?

The double slip is a most confusing point! When the point is set as a crossing the arms show which two tracks are connected. So for a train passing from the near left track to the far right track I want to see the near indicator to the left of the column and the far indicator to show on the right side. However when both indicators show on the same side then the OPPOSITE two tracks are connected. So to pass from near left to far left tracks I want to see both indicators to the RIGHT of the column.

My understanding is that in the period I am modelling there would have been point indicators on all of the points which are on the main line of the Ffestiniog Railway. I plan to emulate this eventually, if these first installations survive, and in the near future add them to at least the other points at Dinas (the upper terminus).

However both the fixings and the alloy sheet have now arrived, so I can go back to the bridge.

Trevor

I've seen these before, they are certainly interesting. The crank would need to face in the same direction as the signal arm itself, rather than being 90 degrees off-set, so when the arm faces 90 degrees downwards and to the right, the crank is also the same and when the signal rod pushes upwards it then moves the crank and arm to the left

I have a feeling that the direction in which the point blades are set at one end affects the direction the train moves at the other end of the double slip. In your second photo I think a train moving through the double slip is effectively going straight through, either left to left or right to right. I saw a very good explanation of this piece of pointwork on a YouTube video from the Southgate Light Railway where he had obtained a second hand double slip operated by a single lever. He explains that whichever route through the point a train is taking it is either crossing over or going straight on. My most frightening experience for a long time when involved with the railway preservation movement was when I was in charge of a shunting move through a double slip which required clamping the blades to set the route, I clamped them and then walked through several times before authorising the movement,

Phil

gilfachphil wrote: Thu Sep 17, 2026 8:16 am I have a feeling that the direction in which the point blades are set at one end affects the direction the train moves at the other end of the double slip. In your second photo I think a train moving through the double slip is effectively going straight through, either left to left or right to right. I saw a very good explanation of this piece of pointwork on a YouTube video from the Southgate Light Railway where he had obtained a second hand double slip operated by a single lever. He explains that whichever route through the point a train is taking it is either crossing over or going straight on. My most frightening experience for a long time when involved with the railway preservation movement was when I was in charge of a shunting move through a double slip which required clamping the blades to set the route, I clamped them and then walked through several times before authorising the movement,

Phil

Yes as shown in the second photo the train would go through left to left. However it won't go right to right without both blades being moved to the other side. I have tried it! The photo was only intended to show how I had mounted the first indicator.


Trevor

Actually perhaps try having the crank attached the rod that moves the arm at the bottom of the post on the opposite side (yellow), so that when the point lever pulls away from the indicator it moves the arm rod upwards, basically an opposite L shape to the current set-up

Just to finish this off:



Trevor

I'm a little late to the party on the bridge, but the design reminds me of the Fox River bridge in Oshkosh, Wisconsin: This example is modern construction but of course bascule bridges have been around for a while. I always thought the top mount was just a hinge but I wonder now if it's a gear like your design... does that make it a rolling bascule bridge?

Trevor Thompson wrote: Fri Sep 18, 2026 7:45 pm Just to finish this off:



Trevor

How confusing. I was wrong. With two entry points and two exit points there are four possible combinations and all have different outcomes. The SLR explanation is an oversimplification,

Phil

gilfachphil wrote: Sat Sep 19, 2026 7:34 pm

Trevor Thompson wrote: Fri Sep 18, 2026 7:45 pm Just to finish this off:



Trevor

How confusing. I was wrong. With two entry points and two exit points there are four possible combinations and all have different outcomes. The SLR explanation is an oversimplification,

Phil

Yes I totally agree! A VERY confusing point.

Trevor

drewzero1 wrote: Sat Sep 19, 2026 7:24 pm I'm a little late to the party on the bridge, but the design reminds me of the Fox River bridge in Oshkosh, Wisconsin:
P6210237_s.JPG
P6210229_s.JPG
This example is modern construction but of course bascule bridges have been around for a while. I always thought the top mount was just a hinge but I wonder now if it's a gear like your design... does that make it a rolling bascule bridge?

I really don't know enough about the technology of Bascule bridges to answer your question. All of the examples I have come across roll on what is essentially a large diameter gear wheel, and have a pinion to mounted on that upper deck. The clever bit is that the pinion is at the centre of the large gear, so as the bridge rolls open the pinion moves horizontally. I wonder who first worked that out?

Trevor