Rivermead Central
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You’re probably right. Might be a market for them!It looks like the kind of part that could easily be 3D printed,
(and the only person who would know would be the chap who painted the 3DP to look like a metal part)
In terms of a ‘museum approach’, there would even be an argument for leaving the 3DP part unpainted. It shows what should be there, but doesn’t pretend to be something it isn’t. As per the missing bits in reconstructed Ancient Greek vases, Roman etc ceramics.
I’m going to keep looking for another Marklin one!
Back in my post #79 (18 April), I reported I had completed repairs of the ‘crossing end’ of the next Lowko Track turnout. I have now repaired (and strengthened) the joints between the tie-bar and the switch blades. These joints had both broken when the turnout came to me (very common), showed signs of an earlier attempted repair (also very common), which had failed (also very common). As explained previously (see my post #4), I do not simply remake all the broken soldered joints in Lowko points — on the basis that the design faults mean the joints will just break again.
My approach to fastening the switch blades to the tie bar means the connection no longer relies on soldered joints — though the joints are soldered, which hides the stronger fastenings I have put in.
Here is an end-on view of the switch blades (tie-bar detached and not present):
The way the rails were made out of sheet tinplate is obvious. The switch blades were created by grinding away essentially one side of the sheet metal rail. The original fastenings between the tie bar and the switch blades were large ‘dollops’ of soft solder — which fracture due to the resistance and flexing of the switch blades during use.
My approach to securing the switch blades to the tie bar is to trap the switch blades between fastenings that will not break. First, to prevent the switch blades moving outwards from their proper position:
I have filed a notch into the tie bar on each side and soldered and riveted on a small nickel silver plate that sits up at an angle. The plates overlap inside and trap the bottom web of the switch blades:
Next, to prevent the switch blades moving inwards from their proper position, I drill a hole through the tie bar just inboard of each switch blade, tap 10BA and put in a countersunk screw, the head of which overlaps (on top) the web of the adjacent switch blade:
Then I re-melt the remains of the original solder fastening to hide the new fastenings and restore the original appearance:
The tie bar will be repainted black to replicate the factory finish.
Even if the new soldered joints were to fail in use, the switch blades would still be held in place by the hidden nickel silver plates and brass countersunk screws. Actually, I am confident the new fastenings won’t fail, but making them is a tedious amount of work.
For this turnout, I now have to modify the original sleeper raft and reposition the point lever so it will fit in the six foot between two tracks.
My approach to fastening the switch blades to the tie bar means the connection no longer relies on soldered joints — though the joints are soldered, which hides the stronger fastenings I have put in.
Here is an end-on view of the switch blades (tie-bar detached and not present):
The way the rails were made out of sheet tinplate is obvious. The switch blades were created by grinding away essentially one side of the sheet metal rail. The original fastenings between the tie bar and the switch blades were large ‘dollops’ of soft solder — which fracture due to the resistance and flexing of the switch blades during use.
My approach to securing the switch blades to the tie bar is to trap the switch blades between fastenings that will not break. First, to prevent the switch blades moving outwards from their proper position:
I have filed a notch into the tie bar on each side and soldered and riveted on a small nickel silver plate that sits up at an angle. The plates overlap inside and trap the bottom web of the switch blades:
Next, to prevent the switch blades moving inwards from their proper position, I drill a hole through the tie bar just inboard of each switch blade, tap 10BA and put in a countersunk screw, the head of which overlaps (on top) the web of the adjacent switch blade:
Then I re-melt the remains of the original solder fastening to hide the new fastenings and restore the original appearance:
The tie bar will be repainted black to replicate the factory finish.
Even if the new soldered joints were to fail in use, the switch blades would still be held in place by the hidden nickel silver plates and brass countersunk screws. Actually, I am confident the new fastenings won’t fail, but making them is a tedious amount of work.
For this turnout, I now have to modify the original sleeper raft and reposition the point lever so it will fit in the six foot between two tracks.
Roger Pound
Western Thunderer
A fascinating solution.
Roger
Roger