digitalizing ef 81 locomotive

[hrnts2000]

Hi to all,

I just joined the site because I started some time to get interested in N gauge models.
I am interested in Japanese locomotives and I try to digitalizing the Hokotusei EF81 electric locomotive model (Tomix 2133).
The model does have not the connector NEM: I will work long and adventurous ....   
you have any tips?
thanks

[CaptOblivious]

Hello and welcome!

Sadly, no Japanese models offer NEM ports, and most are very difficult to digitize. I have the same model you do, and I can tell you: it is hard. You will have to mill out the frame and solder a decoder in. Stevenh has a writeup on his blog http://modelrail.otenko.com
I too have written a bit about adding DCC to this model at my blog http://akihabara.artificial-science.org

The Kato EF81 does take a drop in decoder, with a little modification (digitrax DN163k0a or tcs K0D8) you will have to modify the LEDs on these decoders to shorten the leads, but installation is otherwise pretty easy.

[hrnts2000]

Thanks for the reply. Even I had thought (asking a friend modeler, but he works with H0 gauge) to excavate the ballast to a few millimeters above the engine and place them the decoder. I still have not yet decided which to use, possibly small !
Thanks again, now I read the reports on the sites you gave me.

[CaptOblivious]

I should hasten to add that my success with the TCS CN-GP decoder was limited. It worked for a while, and then blew the motor driver. TCS tech support told me that they are very delicate decoders, and it is easy to do what I did. Currently, my EF81 has no decoder, as I investigate how best to recover!

[stevenh]

hrnts2000,

My biggest issue with putting the Hornby decoder in my Twilight Express Tomix EF81 was trying to secure the power wires. Since the chassis is an alloy, it's quite difficult to solder to with my low-powered soldering iron!

You might have more luck, but that will be your biggest issue... make sure you secure the red/black wires as tightly as possible to the chassis.

See the direct link here: http://modelrail.otenko.com/dcc/ef81-twilight-express-dcc-decoder-install
And the rest here: http://modelrail.otenko.com/category/dcc/dcc-decoder-install

[CaptOblivious]

I'm thinking for my next attempt, I'm going to use one of the lightboards as my frame pickup, soldering the wires to the lightboard, and cutting the traces to isolate the lamps...

[westfalen]

My biggest issue with putting the Hornby decoder in my Twilight Express Tomix EF81 was trying to secure the power wires. Since the chassis is an alloy, it's quite difficult to solder to with my low-powered soldering iron!coder-install

I've gotten around this with some decoder installations by drilling and tapping a small brass screw into the chassis and soldering the wires to that.

[hrnts2000]

Thanks to all for the information and the very interesting link! I examined the description of the installation of decoders and I decided that for TCS, because the two components of the circuit should be without major changes to replace the two boards lighting model. But if it "dies" like that of CaptOblivious .... I think over again, and maybe try other news about the reliability of these decoders. Just charge the batteries in my camera I posts on he forum an image of "child"! Thanks for the info, I will keep you informed on the progress of work!

[CaptOblivious]

The frame modifications for the TCS CN-GP were actually surprisingly tedious and difficult. And, I fried something like four of the CN-GPs trying to make them work? I really cannot recommend the CN-GP for this locomotive anymore.