Alright, its been a month, but starting tommorow, i hope to begin constructing more bridges. I'm going to leave the details for later, only installing the insulators and such so i can begin hanging wires. Right now, the problem i'm having is i ran out of the brass wire i was using and i haven't been able to find a suitable replacement. I'm going to need a TON as well, since all those grab irons add up, and i go through them faster using the jig my friend made.
I should have enough material to construct at least 3 more catenary structures, possibly a fourth if i can reinforce an old IHC signal bridge kit to fit in a particular location (it is so light that the pantographs can push it out of alignment).
These new bridges will be special. They will have thicker cross beams, as is Pennsy policy on curves. They will also require lots of tweaking. There are a number of considerations:
1.) how far to offset the hangers on the catenary bridge. the wire is "banked" on curves, so the location where the hangers attach to the bridge and where the wires hang are offset from each other. luckily, on tight curves, elongated "clips" are not required between the trolley and auxiliary wire.
2.) How far to offset the wires. the Pantograph shoes of an HHP-8 and a GG1 follow totally different paths (the G's pans tend to be offset). I have to find the right distance so that their shoes can glide easily on the wire
I plan to fix this by putting attaching the hangers to the crossbeam, but not soldering the ends together. essentially, the "y" shape will not be completed (yet). I will then tweak the more "horizontal" wire that will hold the trolley wire until it looks like it is about right (after rolling a GG1 and some other electrics through), and then solder the other (supporting) end of the hanger, to complete the "y".
The transmission lines will also be offset on the top. On tighter curves, i've seen them move the outer-most transmission lines to one side (one example would be on the NY&LB (North Jersey Coastline) above the Outerbridge Crossing ramp. I figure this will also keep them safe from people bumping them ( I've already hit two transmission arms :wall1: ) It appears that on tight curves, the pennsy (or in the current case, NJ transit) alternated between the "standard" transmission arm set up, and the "double on one side" set up.
In the future, i'm going to have to modify these bridges and the ones i've installed a bit to accept the pull off wires of the crossovers they bracket. I think i can do that while i hang the wires after the bridges are solidly installed.
here is a diagram of approximately what the next two bridges will look like. I'll probably build two more of a similar design, though I'm banking on maybe creating some pure wire cross spans instead of all K-braces in the future.
and just for the hell of it, here is a shot with my unfinished catenary bridges.
Elite Juice Jack Modeler.