Hornby SW-1 DCC sound install

[rhiadon]

I've just started doing my first model railroading. I've been a kind of spectator for many years but finally got the space to actually start doing some experimenting and learning. For some reason I decided to make things as difficult for myself as possible and I want to model the Pere Marquette in N scale. When I saw these Arnold SW-1's I was pretty ecstatic because the Pere Marquette used 2 of them. This gave me a great opportunity for lots of learning. I get to learn how to redecco 2 Penn Central units into PM paint. I get to figure out how to put DCC sound into these things as well.

Turns out it's quite plausible to pull off with some modifications. I've managed to put a SoundTraxx ECO-100 diesel decoder in the thing.

To do this I had to do the following:

1. Remove the stock PCB
2. File down the metal nubs on each end of the frame above the worm gears
3. Remove the shrink wrap shell from the SoundTraxx decoder
4. Remove both connectors from the PCB of the SoundTraxx decoder
5. Hardwire each of the wires to the decoder
6. Glue in some grain of wheat light bulbs for the front and rear lamps
7. Find a supply of really tiny speakers. I'm using a Zimo 8x8x12 speaker.
8. Regauge the wheels. I just did this with my fingers instead of a gear puller. Maybe this is less than ideal as it moves one wheel farther away from the gear, but it seems to work great.

I'll be finishing up tonight as my Zimo speakers just arrived in the mail. I'm pretty excited to hear this thing run around my test track. I already bought a Zimo 11x15 speaker as it was the previous smallest I could find, but it's too big so I ran without the shell. Still cool. Sound makes all the difference in my opinion.

This is my first one so there was a lot of experimenting. The second one will go better and will be cleaner.

User peteski expressed interest over in another thread and suggested I start a new thread on this subject.

Let me know what you guys think.

[Lemosteam]

@rhiadon I would love a description of each pic!

[rhiadon]

Kinda new to the forum, or forums in general really. Let me see if I can figure out how to edit the post to add some text for each picture.

[rhiadon]

I can't figure out a way to edit the original post so I'll add some description here.

Picture 1: This is the chassis of the Hornby SW-1 with the stock PCB removed and the SoundTraxx ECO-100 installed. If you look close and are familiar with the ECO-100 you'll notice the removed connectors. This was necessary to get the decoder to fit in the shell.

Picture 2: A picture of the same, now with the shell installed minus the hood. This actually has the speaker in the cab. You can't see the speaker, but that's kind of the point. You can see some of the SoundTraxx micro connectors that I'll use for the light install. Since those lights are installed in the shell, I needed a way to disconnect the shell from the chassis.

Picture 3: The top locomotive is another Hornby SW-1 with the shell removed and a 6 pin DCC decoder installed. The bottom loco is of course the modified unit with the speaker shown. It's tiny but it sounds great!

Picture 4: Same as 3 but from a slightly different angle with the focus on the front unit.

[ChristianJDavis1]

Do you have the capacity to take a video recording of the unit in action? I can safely assume that I am not the only one here who is curious as to how the units sounds when all together. It is efforts like this that advance N scale and put it to the league of larger scales. Great work.

[rhiadon]

I do using a cellphone. I'll give it a try and see about posting it to youtube. I'll make sure to not do vertical video. I'll post tonight.

[Scott Lupia]

I was thinking to myself, "man, this guy is just getting into the hobby and installing sound in the SW1".  That's ambitious.  Then I saw the pics and read your writeup.  Whoa!  You are nailing it.  That is just plain impressive.  Fantastic work.  I am going to have to try this out.  The sound of an EMD 567 eminating from a pup is just too cool not to do.  Thanks for putting this out there for us.

scott lupia

[rhiadon]

Thanks for the comments Scott.

It might be of note that I'm an Electrical Engineer with some good soldering experience. Good soldering skills are pretty much required for this to ever work. You'll be soldering wires directly to some very fine pitch solder pads. It's totally doable, but not for the faint of heart.

I plan to do a full series of photos for round two of this install. I have a second unit to do this too and this one was the experimental unit. I got to figure out what worked and what didn't and make the mistakes on this unit. The second one will go smoother and quicker and should be even cleaner.

[Viperjim1]

Oh thanks a lot ! I had my hopes up on,any common person could do this without any problem. And then you drop the bomb " electrical engineer" lol thanks for the illustrations.

[peteski]

Oh thanks a lot ! I had my hopes up on,any common person could do this without any problem. And then you drop the bomb " electrical engineer" lol thanks for the illustrations.

Soldering is simply a learned skill which should be within reach of any common person, especially if that person is in a multifaceted hobby such as model railroading, for extended period of time.  There are few rules which should be followed and it does take practice (and having good equipment also helps greatly), but it is doable.

A decent quality adjustable-temperature iron with changeable tips costs less than a model locomotive, but it will make your soldering jobs much easier. So will thin-diameter solder (for those tiny solder joints) and using flux is a must.  So is keeping the soldering iron's tip clean and tinned. But above all, practice, practice...  So keep installing those wired-in decoders and in no time you will actually enjoy soldering! 

[rhiadon]

Oh thanks a lot ! I had my hopes up on,any common person could do this without any problem. And then you drop the bomb " electrical engineer" lol thanks for the illustrations.

Sorry to rain on a parade. I don't think Electrical Engineer's have a monopoly on soldering skills. There's MANY people who are not EE's with better soldering skills than I. I just wanted to set the proper perspective and expectations. I suspect this is not a typical beginner project. There's a bunch of risk involved because you void the warranty on two things: the decoder AND the locomotive. If you;re OK with the risk, go for it. It's a fun project!

[peteski]

That is true. Just because an EE designs a circuit, he doesn't always necessarily build it himself.  Actually, when I was a hardware tech in the 80s, we troubleshot electronic circuit boards and when we found a bad component, the circuit board  was sent to rework.  There the component was unsoldered and replaced with great skill by a staff or "rework ladies" (mostly women 40-60 years old). Most of them did a really good and clean job, but we did have couple of "butchers" we tried to avoid.  But most of those ladies had really good soldering skills (and I bet you none were model railroaders and they weren't EEs either).

[jdcolombo]

Very nice - I was about to buy an SW1 to see if I could do this myself, but now that you've proven it can be done, I'll tackle some other projects.  Since I've never used the ECO-100 DIESEL decoder, would be anxious to hear how this sounds in a video.

If the ECO100 will fit, an ESU LokSound should as well - they are almost the same size, except that the ECO is about 2mm longer and 1.5mm thicker.  I really like ESU's EMD567 sound files, although they don't have a V6-specific one (the SW-1 used a 6-cylinder 567A or 567B; the majority of EMD's switchers used a V12, and LokSound does have a specific file for that prime mover).  But I suspect that the ECO-100's 567 non-turbo file is the V-16, since that was the most common version of that engine, used in nearly all of EMD's cab and road-switcher units through the 1950's, so it really doesn't matter much.

Great work!

John C.

[rhiadon]

I looked at the ESU Micro decoders and decided against them because of the price. Who-boy are those things salty. I'm sure they are worth it, but for a learning attempt, not the way to go. I imagine the thickness of the decoder might be a killer as well. The reason I had to remove the stock connectors from the ECO-100 was because they were hitting the shell. If the ESU Micro is a little thicker because of actual components used, then it might be difficult to get the shell on.

It will certainly be interesting to me if you guys can identify which 567 prime mover this actually is. I'm no rivet counter so it'll be trivia for me, but still fascinating. It sounds like an old farm tractor starting up to me. It's neat even if it's not technically the correct prime mover.

[peteski]

If the ECO100 will fit, an ESU LokSound should as well - they are almost the same size, except that the ECO is about 2mm longer and 1.5mm thicker.

The way I read this it is the ECO (Not ESU) that is longer and thicker.