Frame repair ? CN GP install gone bad

[mu26aeh]

While trying to install a CN GP, I snapped tab off one side of frame where the decoder board slides in.  Is there any way to repair this, and if not is there any way to continue with the CN GP or switch to a hard wire decoder ?

[Philip H]

I don't know if any way. The metal isn't really conducive to soldering. Frankly you can probably get a new frame off eBay fairly cheaply.

[Wutter]

I'm not sure if there is a way to easily repair the frame.

However you can solder a wire between the pad on the side with the broken frame and the pickup strip that goes to the trucks. This will achieve the same results as that pad is essentially connected to the rail electrically when everything works as designed.

[nsbob]

You might want to try JB Weld.  You can purchase it at any auto parts store or the auto section at Walmart.  However it is non-conductive.  Like Alvin stated, you could use a jumper wire for conductivity.

[mu26aeh]

The engine is questions an early Atlas/Kato RS11/12 .  No pick up strips so I think that takes the wiring suggestion out.   

[Mike C]

Don't know if it would work , but there are metal puttys and metal epoxys out there .

[Wutter]

The engine is questions an early Atlas/Kato RS11/12 .  No pick up strips so I think that takes the wiring suggestion out.

Having no pickup strips makes it a little bit harder but another way to do it would be to drill and tap a hole into that side of the frame and then screw in a small copper tab with something small like 0-80 or a 00-90 screw.

[jdcolombo]

I don't think there is much you can do with the frame - a screw MIGHT work, but if it were me, I'd do this.

Normally, the frames had two sets of tabs for two light boards, one in the front and one in the rear.  I'm assuming from your description that you just snapped the tab off ONE of these locations (either front or rear) but not both.  If I'm right about that, then your best course of action is to hard-wire a small decoder, like an ESU LokPilot, Zimo MX621, or similar size from TCS or Digitrax.  You can use the light board for the end of the locomotive with the tabs intact as both a source of power for your hard-wire decoder and (if you want) for the LED (although I'd replace the LED with a warm-white one; the old LED's looked pretty yellow).  To do this, make sure you cut the traces from the pickup pads to the LED.  Then you can separately wire the LED with your own dropping resistor.  Use the traces from the pickup pads (before the cut, obviously) to wire the red and black decoder wires to.  Wire the motor as you would have with the TCS GN, and then do your own LED for the end of the loco where the tab is broken.

John C.

[mu26aeh]

I don't think there is much you can do with the frame - a screw MIGHT work, but if it were me, I'd do this.

Normally, the frames had two sets of tabs for two light boards, one in the front and one in the rear.  I'm assuming from your description that you just snapped the tab off ONE of these locations (either front or rear) but not both.  If I'm right about that, then your best course of action is to hard-wire a small decoder, like an ESU LokPilot, Zimo MX621, or similar size from TCS or Digitrax.  You can use the light board for the end of the locomotive with the tabs intact as both a source of power for your hard-wire decoder and (if you want) for the LED (although I'd replace the LED with a warm-white one; the old LED's looked pretty yellow).  To do this, make sure you cut the traces from the pickup pads to the LED.  Then you can separately wire the LED with your own dropping resistor.  Use the traces from the pickup pads (before the cut, obviously) to wire the red and black decoder wires to.  Wire the motor as you would have with the TCS GN, and then do your own LED for the end of the loco where the tab is broken.

John C.

That's kind of what I was thinking I was going to have to do.

[woodone]

Drill a small hole where the tab is broken off. Drill a .030 hole and use a brass rod .030 in diameter and insert in the hole now just a quick solder job to solder the pin to the board.

[mu26aeh]

The other question I had was these motors seem to have a metal casing on them.  Is it better to wrap tape around the motor or try to line the interior of the frames ?

[peteski]

The other question I had was these motors seem to have a metal casing on them.  Is it better to wrap tape around the motor or try to line the interior of the frames ?

I never heard of the motor causing short between the frames on any of those early Kato models (RS-3, RS-11, etc).   Pretty much all the motors used in locos with metal frames have metal bodies (the end holding brushes is plastic).  I wouldn't worry about this.

[jdcolombo]

I never heard of the motor causing short between the frames on any of those early Kato models (RS-3, RS-11, etc).   Pretty much all the motors used in locos with metal frames have metal bodies (the end holding brushes is plastic).  I wouldn't worry about this.

Agree - I've installed dozens of hard-wired decoders in older Atlas/Kato locos, including older RS3's and geeps.  Never had a problem with the motor causing a short.  However, DO make sure to insulate the frame from where you solder the motor wire to the brush.  I usually just put a little kapton tape at this spot, but a small piece of electrical tape will work just as well.

John C.

[Wutter]

One thing that I forgot to mention that would also work (and would be a little simpler than the screw).

If there is only one broken tab total, you can wire the pad from the other half of the board over, just make sure you don't accidentally cross frame sides. This will allow you to tape down the board or something after you've soldered on the "jumper wire" from one half to the other.

Just saying, lots of options whichever route you choose to take.

[jagged ben]

Doesn't the CN-GP pick up power from either end?   Unless I'm wrong about that, this is all much worry about nothing.   See jdcolombo's post and stop reading at the point where he starts talking about other decoders.