Bachmann N-class - How I did it.

[gz3xzf]

Bachmann N-class - How I did it.

I decided that I would add a decoder to one of my Bachmann N-class locos, I had a couple of Bachmann 36-553 decoders awaiting fitting, so the stage was set.
I looked at the very helpful Bromsgrove Models page dealing with this loco and made a start.
On stripping down the locomotive I found that the Bachmann decoder wouldn’t fit in the engine as described in the Bromsgrove page (note to self, make sure you know what you are doing!! ). So I fiddled about a bit and decided that it could go in the tender; not so much of a problem as the engine and tender are permanently coupled.
Here is what I did: -
First I decided that the small printed circuit board would be helpful (I have found that Ian Abel has posted a guide here for the Bachmann N Class fitting in a similar way, but it shows the circuit board in more detail): -

I removed the components: -

I then removed the 8-pin plug from the decoder and tied up the lighting wires in a loop. I had noticed that there was a convenient pair of holes in the loco to tender coupling plates that would be a good route for the wires, I decided that it would be a pain having to thread the wires through both holes so I cut a slot in the plastic tender body: -

Now I threaded the four wires through the loco buffing plank and made sure there was a free route to the firebox without being trapped, time now to solder the decoder wires to the locomotives circuit board. I used the holes where the components were removed earlier; a bit of thought needs to go into which wire to solder in which hole, but if you use the photo as a guide you should be OK: -

I wired as described on the Bromsgrove page: -

    Decoder ---> Loco
    Orange ----> Motor Red
    Grey -------> Motor Black
    Red --------> Pickup Brown
    Black ------> Pickup Black

Here is the circuit board back in position: -

Replace the loco body making sure the wires are routed between the screw head under the cab and the small piece of framing, you should find the wires are still free to move once the chassis is secured to the body.

Remember to put the tender coupling bar back in place before you fit the rear screw in the chassis (you may realise that I didn't do this and had to take it apart again! ). At this point I tested the loco on the track to ensure the decoder was correctly wired and travelled in the correct direction.
Now position the tender and locate the wires in the hole and down next to the screw hole in the tender body: -

Fit the tender chassis like so: -

Last thing to do is fit the tender couple retainer in place and test: -

 

I have since contemplated fitting the tender with pickups, I will possibly do something about this when the time comes for the next of my N class locos get a decoder.

Hope this is helpful.

[JoeJ]

This is a brilliantly documented conversion, those photos make everything so much clearer! 

I've got a few 8 pin Lenz chips which are roughly the same size as the standard Bachmann 8 pin ones, so I knew I'd have to put the decoder in the Tender, thanks for showing us all how you did it!

 

Joe,

[Ian Abel]

Bachmann N-class - How I did it.

 

I decided that I would add a decoder to one of my Bachmann N-class locos, I had a couple of Bachmann 36-553 decoders awaiting fitting, so the stage was set.

I looked at the very helpful Bromsgrove Models page dealing with this loco and made a start.

On stripping down the locomotive I found that the Bachmann decoder wouldn’t fit in the engine as described in the Bromsgrove page (note to self, make sure you know what you are doing!! ). So I fiddled about a bit and decided that it could go in the tender; not so much of a problem as the engine and tender are permanently coupled.

Here is what I did: -

First I decided that the small printed circuit board would be helpful (I have found that Ian Abel has posted a guide here for the Bachmann N Class fitting in a similar way, but it shows the circuit board in more detail): -

N Class DCC 01.JPG

I removed the components: -

N Class DCC 02.JPG

I then removed the 8-pin plug from the decoder and tied up the lighting wires in a loop. I had noticed that there was a convenient pair of holes in the loco to tender coupling plates that would be a good route for the wires, I decided that it would be a pain having to thread the wires through both holes so I cut a slot in the plastic tender body: -

N Class DCC 07.JPG

Now I threaded the four wires through the loco buffing plank and made sure there was a free route to the firebox without being trapped, time now to solder the decoder wires to the locomotives circuit board. I used the holes where the components were removed earlier; a bit of thought needs to go into which wire to solder in which hole, but if you use the photo as a guide you should be OK: -

N Class DCC 03.JPG

I wired as described on the Bromsgrove page: -

 

    Decoder ---> Loco

    Orange ----> Motor Red

    Grey -------> Motor Black

    Red --------> Pickup Brown

    Black ------> Pickup Black

 

Here is the circuit board back in position: -

N Class DCC 05.JPGN Class DCC 04.JPG

Replace the loco body making sure the wires are routed between the screw head under the cab and the small piece of framing, you should find the wires are still free to move once the chassis is secured to the body.

N Class DCC 06.JPG

Remember to put the tender coupling bar back in place before you fit the rear screw in the chassis (you may realise that I didn't do this and had to take it apart again! ). At this point I tested the loco on the track to ensure the decoder was correctly wired and travelled in the correct direction.

Now position the tender and locate the wires in the hole and down next to the screw hole in the tender body: -

N Class DCC 08.JPG

Fit the tender chassis like so: -

N Class DCC 09.JPG

Last thing to do is fit the tender couple retainer in place and test: -

N Class DCC 10.JPGN Class DCC 11.JPG

 

I have since contemplated fitting the tender with pickups, I will possibly do something about this when the time comes for the next of my N class locos get a decoder.

Hope this is helpful.

Bryan,

  Nice job. Re: tender pickups, I am thinking of adding pickups to the tender also - been looking at the DCC Concepts "Wiper Pickups" http://www.dccconcepts.com/CatalogueRetrieve.aspx?ProductID=9129692&A=SearchResult&SearchID=42139693&ObjectID=9129692&ObjectType=27

as they look like just the answer for the "N" and various other projects, including my Bachmann 9F. I may consider re-situating the decoder also at that point too.