4-4-0 Damage Photo--The case is Sol-ved

[SpaceMouse]

Here is a photo as best I could get of the damage to the 4-4-0

There are two wires that have come loose. Just below the A you can see a white wire. It has a short piece of electrical tape attatched and about 3/32" exposed. To the left of the B is a grey wire. It two has about 3/32" exposed. To the left of the C is a post that I think might be where the grey wire attaches. I have no idea where the white wire would go. Any help would be appreciated.


If this does not enlarge click here:
http://www.vitaconnect.com/Photos/4-4-0.jpg

[SpaceMouse]

According to my handy-dandy Andy Sperandeo book, the grey wire goes to the engine and the white wire goes to the front light. Okay, now I just need to figure out where the missing half of the white wire went.

[rrinker]

The grey wire should go to the motor, at that post you indicate at C. The orange wire there should fasten to the other post on the motor.
Blue and white go to the Headlight. If it's a light bulb, it doesn't matter which lead connect where.
That looks like heat shrink, not electrical tape - you're going to have to cut the wires back, slip on some new heat shrink, twist and solder the wires, and then slide the heat shrink up and shrink it.

--Randy

[rrinker]

Oh, and I REALLY hope the grey wire isn't touching the orange wire or the post. Because if it is - dead short across the motor drive of the decoder = poof!

--Randy

[SpaceMouse]

The grey wire was not touching the orange post when I took it apart. Back to the light.

I cannot get to the light itself, but coming from the area where the light would be are two wires: One black and one black/white. The black attaches to the blue on the decoder. The black/white attatches to the right one of two posts above the front truck. When I put on my glasses I could see that you were right Randy, that was heat shrink, not tape, and what I thought was exposed wire was a short piece of black/white wire.

Using deductive reasoning:

The white wire (with black/white tip) is cut off and too short to reach the black/white wire on the post.

The light is VERY tough to get to, so he probably didn't change it.

He would therefore need a resistor between the white wire and black/white which isn't there.

He cut if off and left it hang, for future completion OR he already blew the light and want to protect the decoder from future damage.

How'd I do?

[rrinker]

Well, those IHC things probably have 12v bulbs to begin with, and probably did not need changing. Not everyone uses the low voltage bulbs like P2K.
Whenit fell, did the tender and engine become seperated? Otherwise I don't see how it would have pulled the wires loose at all. I guess the obvious question is, did the headlight work before it fell?
I've never seen one of the newer IHC locos, so I don;t know if there is a way to remove the boler front or the weight from inside the boiler to get to the light bulb. If there's not enough wire to reach, you will either need a new bulb, or at least get at the existing one and splic in additional lengths of wire. But if you are goign to go through that trouble get an LED and resistor and use that. I've sort of set that rule for myself, if i HAVE to change the bulbs out, then I will use LEDs if at all possible - especially on such locos that are hard to take apart.

--Randy

[mcouvillion]

Chip,

Look in the boiler to see if there is a screw holding the weight in place. It might be in the smoke stack or under the boiler. The weight may already be "loose" but stuck in place with tape or glue. Remove the weight to get to the headlight.

Post a picture of the front of the engine. You may be able to take the entire front of the boiler off by prying gently between the end of the boiler and the boiler itself. You would just have to align it properly when re-assembling it.

If someone put it together, unless they really glued it together, someone else can get it apart and repair it. Don't despair. You haven't found the secret yet. It's there. Keep looking.

By the way, a neat little technique for soldering tiny wire in tight places is to strip and tin the end about 1/8" (or less, if possible) on both ends to be connected, slide a piece of heatshrink tubing about 1/4" long over the longer wire, then position the tinned sections of wires adjacent to each other such that they overlap completely and heat them up. The junction will be strong enough for the small wire and there won't be a big bump in the insulation. For two wires (4 ends), offset the junctions such that they will never make contact with each other once connected. Put the heatshrink tubing over one wire pair before starting. Slide the heatshrink tubing over the junction(s) and heat it to shrink it. (Wait until your original solder joint has cooled) Great for tight places. Try it.

Good Luck.

Mark C.

[SpaceMouse]

Mark,

The bolier front did come right off and low and behold the resistor was inside the boiler.

It is connected to the black/white wire that runs to the post above the front truck.

However, the mystery to me is why the white wire was cut off.

The other mystery to me is how the light circuit operates. On all my other locos they simply plug into the DCC socket. This one runs to the post above the trucks. Shouldn't it run to the white wire, or does the white wire run to the post?

[SpaceMouse]

It seems he did it on purpose. I found this in an online search.

You have the option of operating your headlights at full brightness. To do this, you must use the blue wire. However, many steam locomotives have metal bodies where one side of the headlight is grounded to one of the wheel sets picking up power. You may elect not to use the blue wire and leave the headlight grounded. It will operate at half brightness.

[SpaceMouse]

I soldered the grey wire put the case back on and it works. The headlight runs at 1/2 brightness.

[rrinker]

Yup, it's using half-wave power. For good reason - if the current draw of the light bulb is high enough, the required resistor to hook it up 'normally' to the blue and white wires on the decoder could be a 1 watt or higher resistor - and 1 watt of heat inside the confines of the boiler shell will shortly result in a meltdown.
For half-wave power you connect the white wire from the decoder (function F0F sink) to one side, and the other side to one of the rails (hence the connection to the truck you see). I'd check back in the tender to make sure those colored wires ARE attached to the decoder itself , but assuming they are, the one side of the light bulb/resistor that connects to the decoder has to be on the WHITE wire for it to work, NOT the blue wire. Connecting the blue - I'm not sure what would happen. Probably not good.

--Randy

[mcouvillion]

Chip,

Glad you figured it out. You've come a long way in just over a month. Kind of scary that someone picks up stuff that fast. Congrats.

Mark C.

[SpaceMouse]

I still don't feel good about putting sound in my son's Hogwart's but today was a big step. I couldn't believe how little room there was in that 4-4-0.