Kato C57-180 "Banetsu Monogatari" decoder install

[Martijn Meerts]

This isn't a complete install yet, but one I've been working on far a while. Funny enough it's in a locomotive that's been talked about a bit in a different thread (Kato re-releasing the Banetsu Monogatari event train in the new colour scheme, and MicroAce also releasing a C57-180 in the new colour scheme)

 

I've attempted to install a decoder in this loco before, with limited success. I had to superglue and other questionable ways to attach wires to the frame. It worked fine at first. After being in it's box for a few months (I hate not having any space to even put up an oval :/), I wanted to run it a little on my roller stand. I put it on the stand, but had forgotten which decoder address it had. So, I went into programming mode, read the decoder, and noticed that the CV that says whether there's a short circuit said that there was a short circuit on the motor. So, time to take it apart and see what's going on. Of course, the wires let go of the frame the moment I took the shell off, and I figured it was time for some research.

 

Anyway, as I mentioned in other threads, the metal frame of these loco's is made of a material that dissipates heat really fast. That makes it near impossible to solder anything onto the frame directly. You would need either a VERY powerful soldering iron or a small torch. Disadvantage of either of those methods is that you need to take the locomotive apart completely. Any plastic bit still left on the frame will melt. Not too mention the entire frame will be far too hot to touch, and the metal cools down real slow.

 

Another way to solve it, would be to use superglue or epoxy to glue some copper or brass plates onto the frame. This works to some extent, as long as you make sure you solder a wire on to the plates first, and you need to make sure the plates make a connection with the frame. Superglue and epoxies don't conduct electricity. Also, superglue doesn't hold too well on the frame. I've used this method twice, once with success (I think at least, the loco ran fine after conversion to digital, but it has been in the box since I tested it way back) and once with no success at all.

 

So, then I read about American prototype modelers having the same problem with their Kato trains. Their suggestion was to drill a hole into each frame half, tap some thread in it, and then insert a screw. You can then solder the wire on the screw. This, to me, sounded like a good and very stable way of doing this. Tiny screws like that require very little power to heat up, so they're easy enough to solder on. Add a bit of threadlock on them, and they won't be going anywhere either. So, after a quick hunt for a suitable tap and die set, I was ready to try this.

 

The drill I used is a Tamiya 1.0mm one, which I use together with the Tamiya pin-vise. You can use an electric drill or a Dremel or some such, but I needed accuracy more than speed, so a hand drill or pin-vise was the way to go. The tap and die set I use is from Conrad in Germany. They have an international store and have a LOT of interesting stuff. I couldn't find a set that was small enough in the local hardware stores, but Conrad had one specifically for modeling. It includes taps and dies for 1.0, 1.1, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2 and 2.5.

 

 

This image shows a 1.0mm hole on the left frame half, and a 1.2mm screw in the hole on the right frame half (and a lof of drilling/tapping residue, need to clean that up ;))

 

 

 

Next image shows both screws in place.

 

 

 

This is a sideview of the screws. The screws were actually 2cm long, so I had to cut them to length. I left them a bit longer than the parts of the frame I put them in. This allows me to solder on either end, depending on how much space I have to work with.

 

 

 

And the last one for now, a test fit of the motor. You could say it barely fits, but since it's N-scale, I'd call this plenty of space ;) The orange and grey wires are the ones for the motor, I already connected those during the first install. The thin copper wires are coated wires of around 0.02mm thick, and they are for the headlight.

 

 

 

More to follow when time permits.

[Bernard]

This has got to be one of the most intricate installs of a decoder I've ever seen. Talk about what most modelers would call impossible, you're making possible. I look forward to seeing the next set of photos.

Gee, and I was afraid to install a decoder on some of my older Minitrix stream engines I have, now I might take a crack at it.

[Martijn Meerts]

Don't expect too much of further pictures, all that's left really is to solder on 2 wires and put the thing back together ;)

 

As for Minitrix installs, they are both easier and more difficult at the same time. Easier in that you don't need to drill and tap any holes for screws to solder on, but more difficult because they often have very little space. The Japanese steamers tend to have fairly large cabins, which in many cases leaves enough space above the motor for the decoder. With Minitrix it is far more common to have to build the decoder into the tender which creates it's own set of issues. However, when space is a problem, see if you can get a hold of Trix Selectrix/DCC decoders (article number 66838), these are 14x9x1.8mm, and while not the smallest, they are the thinnest decoders available right now.

[CaptOblivious]

Nice.

 

So, do you solder to the screws before or after they are installed in the frame? Is soldering to the screws while on the frame easier than just soldering to the frame directly? If so, any idea why (as I would have expected otherwise)?

[Martijn Meerts]

I'm not entirely sure yet. Since the screws are so small, I think they might get hot enough to solder on real quick, before the heat gets dissipated by the frame. With a fairly powerful soldering iron and high temperature, this might work. It's likely that the frame won't dissipate the heat away from the screw quick enough due do the fact that the heat needs to be transfered from one material to another. Theoretically, that should make quite a difference. Whether that's actually the case I'll find out sometime this week.

 

If not, I'll have to solder the wires before installing the screws, but that makes it difficult to actually screw them in.

 

Unfortunately, I have to spend most my time this week doing overtime, so I can't work much on the trains. On the other hand, I'll have more money to buy new trains  ;D

[Martijn Meerts]

Quick update, I managed to solder wires onto the screws while they were screwed into the frame. It wasn't easy, but I think that was mostly because I had no way of holding the loco, so it was sliding all over the place. The frame does get hot, but it does look like it can't quite move the heat away from the screws fast enough.

 

The problem I have now though, is that the fault CV tells me I have a short on both the motor and the lighting, so I'll need to do a bit of measuring and testing, but that'll have to wait until the weekend probably.

 

I'll put up some pictures of the installed decoder as soon as I have a few moments to spare ;)

[Martijn Meerts]

Well, I managed to fix the problem. After some initial measurements, I didn't notice anything wrong. I then remembered that the fault CV (CV30 in the case of Lenz Gold Mini) needs to be reset manually. After doing that and re-reading the CV, I got a fault on the motor, but no longer on the lights.

 

I took out the motor and added a bit of black electrical isolation tape around the motor contacts in the bottom. Initially this solved the problem, until I put on the shell. Adding isolation tape on the top contacts fixed everything.

 

Now, personally, I'm not entirely comfortable with the way I installed things. There's no telling when (if ever) the vibrations in the locomotive will ever so slightly move a wire or a piece of isolation tape, and cause a short again. But I guess that goes for pretty much any decoder install, even factory installed ones can suddenly be shorted.

 

So here's another batch of pictures with short descriptions.

 

 

Black and red wires soldered to the earlier installed screws.

 

 

 

Close up of the decoder with isolation tape covering the motor contact area.

 

 

 

Overview of the entire loco (not the best of pictures really ;))

 

 

 

This is where the decoder is located with the shell installed. Shell closes nicely btw, but it's a tight fit due to the wires.

 

 

 

This is how it looks from the outside, decoder is barely visible.

 

 

 

And this is the loco on the testbench which I use for programming and test-running trains.

 

 

 

Enjoy ;D

[trainstrainstrains]

• Hi I've just joined, basically because I'm installing a sound decoder into the tender of a Kato C57. I've disassembled the loco and installed the sound decoder in the tender, I intend to get rail power from the contacts on the tender.  I'm very  new at this, I hope I can put it all  back together again. I've taken pictures so I think I will manage. Is there a parts diagram that shows all the parts and how they fit together?  My main concerns at this point are: Does the screw under the motor present a problem for motor insulation? No need to encapsulate the motor in caption tape? Just isolate the contacts? I believed the contact at the bottom of the motor to be the positive side, to be connected to the positive wire from the decoder. But I see you have the orange connected to the  top and the grey to the bottom so I guess I'm wrong.

Edited February 28, 2016 by trainstrainstrains

[inobu]

 

• Hi I've just joined, basically because I'm installing a sound decoder into the tender of a Kato C57. I've disassembled the loco and installed the sound decoder in the tender, I intend to get rail power from the contacts on the tender.  I'm very  new at this, I hope I can put it all  back together again. I've taken pictures so I think I will manage. Is there a parts diagram that shows all the parts and how they fit together?  My main concerns at this point are: Does the screw under the motor present a problem for motor insulation? No need to encapsulate the motor in caption tape? Just isolate the contacts? I believed the contact at the bottom of the motor to be the positive side, to be connected to the positive wire from the decoder. But I see you have the orange connected to the  top and the grey to the bottom so I guess I'm wrong.

 

Not a good idea for the first decoder install to be a sound decoder. It's too costly if something were to go wrong. I would use a cheap decoder first and work your way up to the sound decoder.

 

The most important step is the isolation of the motor. If the DC and DCC short you could lose your decoder and command station. So be careful. 

 

Inobu

[Martijn Meerts]

 

• Hi I've just joined, basically because I'm installing a sound decoder into the tender of a Kato C57. I've disassembled the loco and installed the sound decoder in the tender, I intend to get rail power from the contacts on the tender.  I'm very  new at this, I hope I can put it all  back together again. I've taken pictures so I think I will manage. Is there a parts diagram that shows all the parts and how they fit together?  My main concerns at this point are: Does the screw under the motor present a problem for motor insulation? No need to encapsulate the motor in caption tape? Just isolate the contacts? I believed the contact at the bottom of the motor to be the positive side, to be connected to the positive wire from the decoder. But I see you have the orange connected to the  top and the grey to the bottom so I guess I'm wrong.

 

 

It's been a while since I did the install, so not entirely sure exactly what I did anymore :)

 

The screw is really only holding the motor in place, there's no need to insulate it. Just make sure you insulate the motor contacts themselves well, especially the bottom one.

 

I may have the orange and grey the wrong way around, but that's really not much of a problem, as it's easily fixed by changing a CV in the decoder.

[trainstrainstrains]

Good to know there is no need to order a 2mm nylon screw.

Yes Ive isolated the contacts carefully, specially the bottom one.

I've used the same hair thin wires for the front light as you did. Only I went under the led weight instead of over it.

I think you where right about the motor polarity because the right side of the frame originally made contact with the top contact of the motor and the decoder instructions say to pick up with the positive red cable power from the right side (engineers side) of the track. Still good to know its not critical.

Thanks for everything.

[trainstrainstrains]

The install was successful, picking power from the tender however is not ideal , there is just one spot along the 14 meter loop track where it looses contact and stops, I think it is to do with the 2 contact springs in the tender not having sufficing weight on them anymore (I had to remove some to fit the decoder) or/and the hook between tender and loco momentarily loosing contact occasionally. I'll work on that today. Once I'm satisfied I'll post the install on a new thread.

Without this Martijn's thread I would not have had the courage to do this. So thanks again Martijn.

[Martijn Meerts]

The train should be picking up power from both tender and loco, so there might be a somewhat unstable connection between the tender and loco.

 

Good to hear it's worked out though, the reason I post installs (especially the more difficult ones) is to help people, so I'm happy that it helped someone :D