Conrail SD38 and MT6 project

[TJ]

I have always loved Conrail's SD38/MT6 slug sets and decided I was going to attempt to build one a few months back. Here is where I am at...


SD38


MT6

For the SD38, I began with the frame and drive. I started with a complete power chassis from a Proto 2000 SD45 and made several modifications.



I ground down the top of each end of the frame to accommodate the small porches of the SD38.



I also had to grind down the bolster and add a pin so its new shoes would fit. Conrail's SD38's were equip with Flexicoil trucks with the clasp style brakes and three high mounted cylinders, these were swiped from a Proto SD7. Part of the frame also had to be removed between the bolster and draft gear area to allow the new trucks to swing freely in all directions.



Finally, the frame was narrowed to a more appropriate width around the fuel tank. This will make room for the traction motor cables to fit between the frame and the air tanks.



I then covered the rough surface of the frame that would be visible from the sides with styrene and filled in the empty space on top of the fuel tank with styrene as well.



With the frame modifications finished, I began working on the traction motor cables. Brian Banna's article on traction motor cable routing was of great help for this part. Too impatient to order the Railflyer pillow blocks, I made my own from styrene and fed lengths of solder through them. .022" solder was the smallest I could find locally, and in hindsight I should have probably order some .015" (as well as those pillow blocks) but it is what it is, now I know for next time.



I think the TM cables turned out well for my first attempt. I did however have to make a compromise on the rear cables. There should be 6 cables running to the rear on each side in a 2X3 block, but due to space restrictions I was only able to fit 4 cables in a 2x2 block. I think I probably could have fit the 2x3 block of cables if I would have used the .015" solder and the etched pillow blocks, but it will have to do as is.



The completed chassis with modified weight.

More to come!

[Randy Earle]

Wow! Look at you! This is a great build!

[icghogger]

Excellent work, TJ, can't wait to see more!!

[cf7]

WOW-- this is awesome! Is the slug going to be powered?

[atsf90]

Wow, those look great! Your work is incredible!

[TJ]

Dec 24, 2011 9:49:22 GMT -5 cf7 said:

WOW-- this is awesome! Is the slug going to be powered?

The slug is indeed powered!

[TJ]

The MT6 slug began life as an old Atlas/Kato RS11. I chose this as a starting point for several reasons. The MT6 I am modeling was built from an RSD12 and since the Atlas RS11 and RSD12 used the same frame and the RS11 are easier to come by this was a good start. The running characteristics of the old atlas/katos are very nice as well and the motor sits pretty low on the frame which was also important to allow for the slug to be powered.

One aspect of the original atlas/kato model I was not happy about was that the coupler box was mounted to the walkway instead of the frame. In the newer release of the Atlas RS11, the coupler box mounts to the frame which I prefer, so I purchased a new frame and walkway. The frame is actually about a scale foot too short to be accurate for an RSD12, but I decided that the amount of work required to lengthen the frame less than a quarter of an inch wasn't worth it.

Now I was time to get started. My first task was to fit the appropriate trucks to the frame. Conrail's MT6's initially used the RSD12's Tri-mount trucks, but were soon replaced with Flexicoil trucks from old SD7 and SD9's. I selected Atlas SD24/SD35 trucks hoping it would be easier to fit them to the Atlas frame.


First I added a .040" styrene shim to each bolster for proper coupler height and drilled a 5/64" hole in the center to accept the bolster pin of the truck.


After mounting the truck, I had to make a slight modification to the frame so the worm gear cover would not interfere with the frame. A little filing did the trick.


A slight modification to the worm gear cover was also required. The upper worm cover in the picture is the stock Atlas part and the lower is the modified part. I had to clip off the rounded part for it to clip on the gear tower all the wall and swing freely in all directions.

With the trucks mounted to the frame all that was left to do was get power from the motor to the gear tower. The worm gears and bearings from the original Atlas/Kato model fit in the newer Atlas gear towers, but the drive shaft was a little too long and prevented the truck from moving freely. I tried a variety of different drive shafts all of which were either too long or too short, so some adjustments were made to the original drive shaft/worm gear set up.


First I removed about 1/8" from the end of the female universal that attaches to the worm gear shaft, this allowed me to slide the universal closer to the gear tower and further from the motor giving the drive shaft some move room. I also had to side the worm gear about 1/8" down the worn gear shaft as well the the universal could be moved as close as possible to the gear tower. Finally I added a .015" styrene shim between the worm gear and one bearing as the worm gear was just a little short for the Atlas gear tower.



The completed truck and drive installation.

[kcs1967]

AWESOME modifications, good use of parts and intelligent method of modifying, well executed and thought out.

[railfan1354]

This is fantastic work. I don't have the patience , skill level, or math skills for this type of project.

Paulie

[Raeder]

Nice work, I like the way things look so far. Kudos, too, for making that booster a powered unit. Those can be tough units to do because there is so little space.

[em1]

VERY nice work TJ!

I've got the "current ownership" of such a set! CSX, Have a look:

SD38,





MT-6,



I'll be the first to say, that these 2 locomotives aren't "brass type details" with all the "bling" so to speak, as I'm not all that much into the diesels themself as I'm normally a steam locomotive detailer/builder but.........They look good for a "basic" detail set.

The SD38 is based off an Athearn SD40-2. (I know there are a few things not exactly right with it.......) I plan to rebuild it since I now know what I left, and should have removed!

The MT-6 is a whole other story.......It began life as a IHC model of a ALCO C-628 (I think) and took 2 of them choped up and re-assembled into what you see pictured!

And yes, both are powered, with directional lights (NO I'm not DCC) ;D

[em1]

Well, I'm not sure what I'm not doing right as the pictures won't post in the thread! Hmmmmm

[tamaman]

NICE work!! love them cables.