The N&W SD50S: The Atlas/Bearden secret now revealed

[fcnrwy23]

Not quite.... but you're getting warm.

OK,  a Intermountain chassis (SD40-2) instead.
Will the frame "Dimples" align with the shells' "Divots".. 

Jerry G.

[u18b]

But there was another issue with this shell.   My memory is fuzzy after all these years, but for some reason I removed the blower duct.   



I vaguely remember the reason being that I wanted the duct to be a separate casting so that a modeler could make an early or late SD50S (or even an SD40X for KCS).

The blower duct on this shell was originally angled but over the years there was a change in the N&W SD50S.  As delivered from the factory, the blower duct was indeed rounded and the left side handrails were flat.   But about a year after delivery the SD50Ss went back to EMD who upgraded the duct to the angled duct as seen on the later SD50 and SD60 models.   This angled duct required the handrails to be raised at that point.     And that’s the way all SD50S units looked at the Norfolk Southern merger.

Round duct, flat rail:
https://www.rrpicturearchives.net/showPicture.aspx?id=3457491

Very same loco, Angled duct, stepped rail, later date:
https://www.rrpicturearchives.net/showPicture.aspx?id=1993568

At present….  I’ll now have put the angled duct back since Aaron and I plan to use stock Atlas SD50 handrails.

[Mark5]

OK,  a Intermountain chassis (SD40-2) instead.
Will the frame "Dimples" align with the shells' "Divots".. 

Jerry G.

I've got a BLI SD40-2 chassis set aside for my SD50S project, if Atlas ever gets the SD50 shells back in stock.

[Mark5]

The blower duct on this shell was originally angled but over the years there was a change in the N&W SD50S.  As delivered from the factory, the blower duct was indeed rounded and the left side handrails were flat.   But about a year after delivery the SD50Ss went back to EMD who upgraded the duct to the angled duct as seen on the later SD50 and SD60 models.   This angled duct required the handrails to be raised at that point.     And that’s the way all SD50S units looked at the Norfolk Southern merger.

Fun trivia. 

[fcnrwy23]

I've got a BLI SD40-2 chassis set aside for my SD50S project, if Atlas ever gets the SD50 shells back in stock.

From what I have purchased this last year.
I get the feeling, they will NOT be restocking anything. In the #493XX series.  (pre-August 2010)
OR
If they Re-release any SD50s.. Only in the NEW stock..  #4000XXXX Series (last batch was made in May 2021).
OR
You find a older NEW/OLD stock shell.  There are some parts available A-bay, with a complete shell for $37.00

Jerry

[u18b]

If others are going to make these….
We might talk about options. 

I was fortunate that Atlas did half the work for me by giving me the phase 1 pre production shell. 

For all else…
1.    Someone print an entire shell and walkway.

2.    You splice an SD50 like I did.   Then, maybe someone could design and print the roof section with extended exhaust silencer and correct roof hatches.
The challenge with option two is that no two people will splice in exactly the same spot.  So the roof section would need to be make a little long and then custom fit the piece.

[Mark5]

You find a older NEW/OLD stock shell.  There are some parts available A-bay, with a complete shell for $37.00

On eBay, I only see an SD60 shell for $37.

I have a saved search for SD50 shells (been watching for a few years ). They'll probably be around $20 if Atlas ever gets around to restocking them - I'm not willing to go too much above that. 

I have endless projects, so I can wait (I guess).

Mark

[u18b]

Using the Atlas Pre-production SD50 body shell, I removed one door from the rear of the engine compartment and spliced it back together.




My SD50 walkway was too long for an SD50S and I needed to shorten it.    This was a slightly harder task than the shell.   I did not cut straight across, but cut in front of a stanchion on one side and behind on the other.  The goal was to get the last stanchions to look reasonable and not out of place. 

So I shortened the SD50 walkway near the rear with the plan to splice the last handrail.   I thought this was better than splicing in the middle where we often pick up our locomotives. 

As stated before, my goal was to reuse the Atlas handrails if possible and not make fine wire handrails.

Having spliced the shell and walkway, I felt I now had a really good SD50S shell.   













The handrails have been cut, but not fused.  That work is still to come.

Since I have the raised section in the handrails on the left side.   Thus I still need to add an angled blower duct back.   

[Mark5]

Nice, I was hoping to be able to something similar with the production SD50 shell (had'nt gotten to the detail phase yet).

I was originally thinking to fabricate handrails from brass wire and GMM stanchions, but your handrail approach looks like it will save me from that agony. 

Mark

[chessie system fan]

Handrails are tricky on SD50+ locomotives because nobody makes stanchions long enough for the raised blower duct area.

[Mark5]

Handrails are tricky on SD50+ locomotives because nobody makes stanchions long enough for the raised blower duct area.

Fixed that. 

[Sokramiketes]

On eBay, I only see an SD60 shell for $37.

I have a saved search for SD50 shells (been watching for a few years ). They'll probably be around $20 if Atlas ever gets around to restocking them - I'm not willing to go too much above that. 

I have endless projects, so I can wait (I guess).

Mark

I picked up an undec SD50 since I needed a mechanism for an SDP40 project.  Happy to offload the shell if that's all you need.  I don't see any SD50 projects in my future.

And Ron!  You carved up a 1of1 preproduction shell that was part of N scale history! Ah! 

[u18b]

Everything you’ve read so far occurred 25 years ago around the year 2000 when I was given that phase 1 shell.

So….  I had created a kitbashed SD50S shell, however, now I had a mechanism problem.   Nothing in production at that time would work (for example, a Kato SD40-2 mechanism was too wide) …. and I never got around to kitbashing a chassis for this shell.  So this unique kitbash sat in a drawer for several years. 

Then in 2007, Intermountain made an SD45-2 (and later they made an SD40-2).   I intended to put the shell on one of those chassis…. but never did.    I had been a little nervous because there are  reports of Zamac rot in some early run IM models.   My first run SD45-2 is fine so far, but others have reported problems from early runs of various locos (especially old F units).  I think that this problem may not have effected the SD45-2 or SD40-2.
See:  https://www.trainboard.com/highball/index.php?threads/intermountain-frame-rot.151894/

At any rate, the SD50S shell still sat in a drawer, out of sight, out of mind.

Then several years later, Intermountain came out with a revised chassis for the SD40-2.   My son, Aaron  (  @chessie system fan  ) acquired a late Intermountain SD40-2 chassis and gave it to me suspecting it would be a better choice.   It was!  The shell was a perfect fit. 



Jerry asked above about whether the frame bumps would hinder the shell/mechanism interface.
The answer is No- because there are none.    On the Intermountain SD40-2, notice the frame has dimples- so the bumps must be molded into the shell.    That alone makes this chassis a great choice and the shell slides down snugly onto the frame.



The icing on the cake was that there would be no need for fuel tank mods.  The stock tank was perfect.



Here is a comparison between the stock SD50 and my shorter SD50S:




Unfortunately, the kitbash sat for a few more years.      :

[u18b]

And Ron!  You carved up a 1of1 preproduction shell that was part of N scale history! Ah! 

I know!
All of the KCS fans are shaking their heads and slapping their foreheads. 

 
 
 

[u18b]

Well,  last month around Thanksgiving 2025, Aaron asked me about that SD50S locomotive and my intentions for it.   Originally, my plan was to make molds of the shell and make castings so other N&W or Norfolk Southern fans could have this great model.   But with the popularity of 3D printing, there was now no point.  Someone could easily draw and print one.

So since my SD50S loco kitbash would never be reproduced for others, it was time to do something with it besides sitting in a drawer, wasting away, decade after decade.   

I offered my unfinished model to Aaron as a Christmas present, allowing him to paint it once I made a few more corrections. 

Here are the remaining tasks which we hope to do over the Christmas holidays:
--Add rear jacking pads since I removed them because they were now in the wrong place once I shortened the walkway.
--Add an angled blower duct.
--Add styrene bits to the bottom of the sill at the curve of the fuel tank.  The rear curves were also no longer accurate since I shortened the walkway.
--Add a spacer to the walkway at the nose and rear so the shell would fit properly on the mechanism and the trucks would not be obstructed by the steps.   I’m placing a shell on a  mechanism that was not designed for it.  So there are big gaps at the nose and tail.  And when you currently place the shell on the mechanism, you have to adjust it to get the trucks to not hit the steps.   The spaces will center everything.
--Double check the splices to make sure all seams are hidden.  I see two handrail stanchion holes needs to be filled.   And one gap looks like it needs filling.
--Fuse the handrail splices.

I’ll then hand it over to Aaron to paint and decal.