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

[Mark5]

Well, not quite.  Notice that the sill is indented above the fuel tank like an SD40-2.  Production SD50s all had a narrower straight sill.

Good eye! Noted and thanks! 

[u18b]

Well, not quite.  Notice that the sill is indented above the fuel tank like an SD40-2.  Production SD50s all had a narrower straight sill.

Wow Aaron.   You're right.
I had not noticed.

[lock4244]

Modeling options:

This photo of 6501 is dated 2000, so they lasted a long time.   Since I model pre-millenial CSX up to the Conrail merger, this would fit my roster also.  (part of me wonders if this photo is mis-dated since it is post-90s and still has no dicth lights).
https://www.rrpicturearchives.net/showPicture.aspx?id=2698366

Other photos show 6503 in NS paint by 1989, so this one is not from 2000.

1989:
https://www.rrpicturearchives.net/showPicture.aspx?id=4369246

1992:
https://www.rrpicturearchives.net/showPicture.aspx?id=4878128

1994 no ditchlights:
https://www.rrpicturearchives.net/showPicture.aspx?id=4281278

1995 with ditchlights:
https://www.rrpicturearchives.net/showPicture.aspx?id=1002160

[Mark5]

Modeling options:

This photo of 6501 is dated 2000, so they lasted a long time.   Since I model pre-millenial CSX up to the Conrail merger, this would fit my roster also.  (part of me wonders if this photo is mis-dated since it is post-90s and still has no dicth lights).
https://www.rrpicturearchives.net/showPicture.aspx?id=2698366

To add to Lock244's post,

In this view, there is a caption "Actual date unknown" by that photo: https://www.rrpicturearchives.net/Locopicture.aspx?id=23427

I don't know why it doesn't "carry over" when you click on the photo.

Here's 6501 in 1996 (NS Paint): https://www.rr-fallenflags.org/ns/ns6501aga.jpg

6501 again in July 2000: https://www.rr-fallenflags.org/ns/ns6501atm.jpg


Mark

[u18b]

Good additions.   Thanks guys.

[u18b]

Now that the loco is back, I've taken some more photos and the modeling may resume soon.

Here's more of a side-on shot of the SD50S shell.






And here is the center section that someone could draw and cast maybe some day.






Inside splice.




And here are some better shots of the walkway joint.  Turns out I did indeed go straight across.  But this should help if someone wants to shorten an SD50 walkway (assuming handrails are the same between the production units and this KCS pre-production shell--- I haven't checked yet.)




And remember the body shell has mounting nubs so new cut-out notches have to be added since the nubs are in a different position in the shortened shell.

[u18b]

Aaron did discover one extra thing.

The SD50S has an extra door at the rear (on each side).

You can see that door here.




On an SD50, there is a large panel instead of door.  As seen in the shell.



It would be really hard to get that panel off evenly.   So we are not going to worry about it.    But if someone were to draw an SD50S shell, then he would want to get the doors correct.

[Ed Kapuscinski]

It would be really hard to get that panel off evenly.   So we are not going to worry about it.    But if someone were to draw an SD50S shell, then he would want to get the doors correct.

It's not like it's a major spotting feature and the odds of messing it up are far higher than the impression it'd make if you changed it.

I have so much respect for folks who make calls like that.

[u18b]

Time to replace the blower duct that I erroneously removed 25 years ago.   



Santa brought me a scrap SD50 shell for the new duct.




Used a razor saw to isolate the duct with some extra.




I trimmed the extra a bit closer and then started sanding on about 400 grit.




Must go slowly.  Constantly checking the thickness of the extra so that it is even all the way around.   If too thick on one side I press a bit harder on that side.




Notice here it is a little fatter at the bottom.  Not even.




When it starts to get paper thin, then I switch to 1000 grit.  Go slowly and check.
Here, the top edge has sanded through but the bottom edge is thicker.   Need to work on the bottom edge more.




Now the bottom edge is coming off.  Need to work on the top of the duct.




Now the top of the duct is coming loose.




A little more gentle sanding and the rest falls away.




Now I need to sand just a little more until the whole thing lays more perfectly flat.   You can see a very slight roundness here.




I removed the handrails and placed the body shell onto the walkway for a test fit and positioning for gluing with superglue.




Once I tack it in place, then I can add more glue.  I apply small amounts using a pin.




Ready to go!

[Mark5]

With thanks to Skibbe, I have an Atlas SD50 shell. I will post pics with comments when I get a chance.

First glance - I will likely compromise on the extended exhaust roof details, definitely not worrying about that extra door rear door.

I do plan to:

• slice and dice (per above)
• modify trucks to be triple clasp (N&W "signature" spotting feature)
• Add proper horn - Leslie 5 Chime (it should be a RS5-T)
• add "bee sting" (cab roof)
• modify walkways to add "indents" for walkway (Atlas "production" shell does not have these)
• Add a frame bell - gotta start looking for a suitable one
• add all weather cab (right side only) - if I have a spare

Mark

[chessie system fan]

• add all weather cab (right side only) - if I have a spare

I have no idea yet what I'm going to do about that. Chessie never had any, so I've never bothered to see what's available. I don't even know what fits an EMD cab. I know there's the GMM set.  Are there any other options?

[u18b]

Now turning attention to the exhaust stack.

The stock detail is a bit weak with little depth.




As you can see here, detail should go deeper.




Roof shots are hard to come by, but here are a few:
https://www.rrpicturearchives.net/showPicture.aspx?id=2385154
https://www.rrpicturearchives.net/showPicture.aspx?id=2148555
https://www.rrpicturearchives.net/showPicture.aspx?id=4958388

So I want to change out the exhaust.

Here is a Kato GP50 exhaust, and it has much better depth, though it might be a bit overscale.




I had an old GP60 casting from years ago and decided to use that.  (made from a kitbashed GP50 before anyone made a GP60).




Used a motor tool and isolated the part.





I want that gap between the exhaust itself and the wall.   So I will remove to the gap (red line).




Part is isolated.




It's a good bit wider than the Atlas exhaust.  When I cut the hole, I will cut to the forward edge of the Atlas exhaust.

[Mark5]

Now turning attention to the exhaust stack.
As you can see here, detail should go deeper.

So they relocated the horn as part of the rebuild (this is "SD40E" #6300 I assume).

[Mark5]

I have no idea yet what I'm going to do about that. Chessie never had any, so I've never bothered to see what's available. I don't even know what fits an EMD cab. I know there's the GMM set.  Are there any other options?

Both GMM and JNJ used to offer All Weather Cab kits. I'm pretty sure that nobody makes them now.

[u18b]

Discussing what Aaron wanted, he discovered another difference.

The KCS sample shell has a much smaller exhaust than the regular production SD50.   Knowing this, the Kato exhaust does not seem so large.




Time to start a hole.




My guide is the front edge of the stock exhaust.




Aaron wanted the gap to be smaller, so I trimmed the edges a bit.




The first task was to get the basic width toward the front (left).   This is all a very slow process so as not to make the hole too big.   The goal is no filler.




I squared up the edges on the left side.





The front edge fits.  I do not want to cut it any wider.




I have a good ways to go in the back.




I need to file toward the back, but I do NOT want to make the hole wider.   So I strategically use my minifile.   Here are two identical files- opposite sides.
One edge is smooth and one is serrated.




Here, I'm filing toward the rear of the loco, but my file has the smooth side against the side edge.   That way there will be no additional cutting at that edge.
Then I'll flip the file and work on the other edge.




OK.  I'm starting to get the front to back width correct.  Getting closer.  Work SLOWLY and check, check, check.




Because there may be an orientation issue with this part, I make sure I'm working in the same direction by adding a little dot.   The dot is away from me (nose to the left).




Ooooo.  I'm getting so close.   I'm working in microns now.




I true-up the corners on the left side, now I see I need to true up the right side.  This is where I use a triangular file to get a sharp edge in the corners.  I'll eventually use a #11 Xacto knife in the corners, but only when i'm REALLY close.




I finally got the exhaust in, but I'm not satisfied.   It's rotated clockwise a bit. 




So I flip the part so the dot is near to me.  And that looks better.




Not perfect (to my eye) but it looks much better.   I work it to get the right height before I glue it in.




The exhaust sticks up just a little like the prototype.




That's enough for one day!