Monday, August 09, 2010

Ozzy makes a reappearance

P1090724

Ozzy the Osprey, who first appeared on this post http://rhydddu.blogspot.com/2007/04/cars-ospreys-vaseline-and-wrong-size.html is learning to be heritage aware and also to ponder the future – hoffs vs tortoises?

Seriously though, I’ve found the problem that has been causing the problem getting the points to move across reliably – it’s the wires soldered to the bottoms of the switch rails, which bond those rails electrically to the stock rails.  This is normal DCC practice, but because the old style points are hard to convert to dcc friendly, the pivot for the blades and the insulated gap are one at the same thing (using insulated joiners).  The problem there is that you have to make the stock rail to switch blade bond before the pivot, causing a new force to be applied to the blade, one which twists the blade slightly, enough to be a problem.  It also happens that the bond wires get in the way of the installation of tortoises below the boards too.  Which is what I found when trying to add a tortoise to the yard point last night.

So, to really deliver reliable pointwork I need to replace the points with the new peco ones.  This then means that the track alignment will have to alter as the points are larger and the divergent angle is less (but this will look more prototypical anyway). 

It also means that I could go with tortoises throughout, but for now I will install the new points (on Ozzy’s advice) and stay with the 3 hoffs I know work fine.  Then after testing, we may have to go for tortoises, but we’ll see.

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