View single post by Huw Griffiths
 Posted: Sat Feb 2nd, 2013 01:12 am
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Huw Griffiths



Joined: Wed Oct 21st, 2009
Location: Cwmbran, Wales, United Kingdom
Posts: 262
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Mark,

A few minutes ago, I retrieved the streetcar I had a go at - and I'd remembered things correctly.

The bulbs in the ceiling are connected in parallel with each other - directly to the pickups and in parallel with the motor. (At the time, I wasn't too worried about this, as I was more interested in looking at my model than running it.)

The chassis can be removed without touching the roof (or anything else above the solebar):
  • Underneath the bodyshell, there's an assembly to represent the truck sides and the lifeguards. It's made of a flexible plastic which doesn't particularly like paint - and held together by a tiny Philips screw at each corner.
  • Thankfully, you don't need to touch these screws. There are 3 round lugs per truck side - a bit like cylinders, with slots running lengthwise straight across the centre line - they can be found at the centre and at the corners.
  • If you insert a small flat screwdriver next to these lugs, the truckside / lifeguard assembly can be eased out - revealing a Philips screw at either end of the chassis assembly (previously hidden by the lifeguards).
  • Removing these screws allows the chassis to be removed complete. You'll then be able to see a circuit board, which carries connections to the yellow LEDs (headlights) and the bulbs (interior lights). There are 2 tracks which run the full length of the PCB - these have "lands" joined to them, which rest on the phosphor bronze contacts for the pickups and motor. There are no breaks in these phosphor bronze contacts.
  • The tracks running the full length of the PCB are connected to the "interior light" bulbs on the ceiling, via red wires at either end of the body. These wires are channelled through rectangular sections in the end glazing mouldings - and are far too visible for my liking.
  • Once each red wire reaches the top of the glazing moulding, it's then connected to a phosphor bronze tag with one end bent up to make contact with the ceiling light PCB. The solder tags are held in place using Philips screws.
  • The headlights at either end are yellow LEDs. They're actually fitted into boxes under the cab floors - with their light being channelled to the outside world through clear plastic mouldings, concealed by black mouldings which look like controllers.
  • Each of the LED boxes under the cab floors is held together by a small Philips screw, driven into a plastic boss moulded onto the underside of the floor - the LED leads are twisted around these, with a blue wire and a black wire running to the PCB. One of these wires is connected (via the PCB) to a motor / pickup spring, while the other goes via a resistor on the PCB.
  • The mechanism itself is nothing too exotic - a motor with a worm and plastic reduction gearing at either end - the whole mechanism is contained in a painted metal block, with a plastic cover to protect the gears. This plastic cover is held in place by the 2 Philips screws which are accessible without removing the truckside / lifeguard assembly - chances are you won't need to touch these.
  • The only strange bits about the chassis are the wheels - on the front, they look like discs - on the back, you can see holes which look like they might have been designed to take bolts. This makes me wonder if they might have been thinking of using the same chassis (or at least the same wheels) with coupling rods.
  • Other than that, the bench seats and floor inside the car body might be interesting (how interesting depends on the initial colour scheme) - I believe they start off the same colour as the bodyshell moulding (before it was painted at the factory). If I recall correctly, this might not be too much of a problem with the "Hershey" version of this model (black, or dark brown) - but mine was one of the "United Traction" ones (very pale cream). I think the benches might also have a bit of a notch at one end.

I hope this helps,

Huw.

Last edited on Sat Feb 2nd, 2013 01:22 am by Huw Griffiths

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