Athearn SW1500 Install

[Espeelark]

Well, here goes nothing!
I took the shell off of my recently acquired Athearn Southern Pacific, DCC-Ready, SW1500. I plan to do a hard install.
So the first thing I did was remove the factory adapter board and test fit a loose LM-3S module inside to see if I could get the shell back on. No dice!
The inside width of the shell is OK until you get to the four fingers of the removable exhaust hatch. These reduce the inside width such that the LM-3S module can't go all the way up into the shell. Look at what the yellow arrows are pointing to in this photo:


I plan to remove those four fingers on either side and glue the removable exhaust hatch into place. That should give me the width needed.

Anyone else do an install into one of these? If so, any tips? Tricks?

I'll update this post as I proceed (may take some time).

[Espeelark]

That worked. I glued the exhaust hatch into place and then used a rotary tool on slow speed to grind off those fingers/tabs.


Here's how I plan to place the LM-3S.


Then I got to thinking about how could I determine the clearance between the top surface of the LM-3S and the underside of the shell. First I drilled through holes into the bottom of each of the exhaust stacks. Figured this would help (marginally) with cooling as well. Then I placed the shell onto the chassis with the LM-3S sitting on top of the motor and inserted a toothpick into one of the exhaust stacks and marked the side of the toothpick.


Now, taking off the shell and holding the toothpick at the same location, I measured ~0.2" of clearance. That should work for the wires that have to pass over the LM-3S.


It's going to be tight but I'm thinking this is all going to work out!

[CPRail]

So far so good! Looking forward to the end. What are you going to use for a speaker and keep-alive?

[Espeelark]

Howdy Ian!
I have a number of iPhone 4(?) speakers on hand, but I think they are too long to fit between the LM-3S and the front of the shell. I was thinking of cutting it down to fit. I have no idea what that will do to the sound characteristics.
Scale Sound Systems advertises a speaker for the Athearn MP15, but no mention of it fitting the SW1500. Suppose I could email and ask.
If anybody has any other suggestions for speakers I'd love to hear them!
At this point I am NOT planning to use a keep-alive as my other 4-axle units appear to be happy with my trackwork.

[CPRail]

JT at Scale Sound Systems has one for the SW1500: AHRR-1500-RC1

It fits over the front truck:
https://www.scalesoundsystems.com/product-page/athearn-rtr-sw1000-1500

[Espeelark]

So I took CPRail's advice and went ahead and got a speaker from Scale Sounds systems.
From what I can tell, it appears to be just narrow enough to fit inside the shell. With the speaker connections on the underside, I got to thinking about how I would route the speaker wires top-side. I could go forward and then up and wrap them around the speaker to go aft, or, go aft and come up right behind it. I didn't like either of those two options so I created a third. I filed two slots into the side of the speaker to route the wires up. I used CA adhesive to glue them into the slot. Here's what that looks like.


Here's what the speaker looks like temporarily installed onto the chassis.


With the speaker in place there will still be space between it and the underside of the shell to allow the wires from the headlight LEDs to run aft to the LM-3S module.

Still lots of space issues to reconcile to get everything to fit. Working on that.....

[ON28]

Good work! I've done some slimming down inside shells, not difficult. I will add I have used copper beading tape in some of my installs instead of wire, I have posted on that.   

[Espeelark]

Continuing to plod along. Difficult to do with the advent of warmer weather and the call of the outdoors, including golf courses. 

I just completed creating four pigtails for the lights: front headlight, front gyralight, rear headlight, rear gyralight.
Each pigtail includes a 1206 sunny white LED, a 15 mA current limiter (in place of a resistor) and a micro, two-pin connector. All have been bench tested and they work.