Atlas/Kato RSD12 resurrection

[nickelplate759]

Nice!

As for painting the Delrin plastic handrails, to minimize paint thickness I do not use adhesion promoter. Instead I sandblasted them with aluminum oxide media shot through a Badger air eraser.  Then I airbrushed a thin coat of Pactra  paint for polycarbonate RC car bodies, followed by the final color of Accu-Paint (Nowadays I would use Tru-Color paint).

Pete - I do not need an excuse for another new tool!

Still, that's a good suggestion.  Airbrushing won't work though, because the NKP painted the railings yellow and the posts black and that's just way to finicky to mask.  I've brush painted these before.  The railing in picture was brush-painted, and yeah it isn't perfect but...it looks OK to my eyes as long as I don't put on the Optivisor.

Final weight is about 3 1/2 oz. An unmodified unit (yes, I have another!) is 3 1/8 oz. Not that I'm at all certain my scale is accurate to 1/8 of an oz.  Anyway, it pulls a 21 car train on the layout with no trouble.

[nickelplate759]

A few more notes and a question about how do to this "right" in the future.

Even with the added weight, this doesn't run or pull as well as much lighter, later designed, units with the axle-end pickups.  I suspect it's mostly a matter of equalization (or lack thereof in this case).    That has me thinking about kitbashing a proper RSD12 at some point.   Atlas has the right Tri-mount trucks in the C628 / C630, but the C628 is not even close to the right truck centers for an RSD12.  I don't want to buy a C628 just to learn about it....  So if anyone has one handy could they look at it and tell me:

1. Do the trucks pivot in their geometric center or at the middle (off-center) axle?
2. Can the trucks used with the frames from other Atlas locos?  If so, which ones?   For example, I think an SD9 or SD35 might be close to the right truck centers for a proper RSD12 - if we are referring to geometric centers.

Also - anyone have pointers to accurate scale drawings of an RSD12?    The "dieselshop.us" web site data is unreliable at best.
http://www.thedieselshop.us/DataRSD12.HTML

[Iain]

A few more notes and a question about how do to this "right" in the future.

Even with the added weight, this doesn't run or pull as well as much lighter, later designed, units with the axle-end pickups.  I suspect it's mostly a matter of equalization (or lack thereof in this case).    That has me thinking about kitbashing a proper RSD12 at some point.   Atlas has the right Tri-mount trucks in the C628 / C630, but the C628 is not even close to the right truck centers for an RSD12.  I don't want to buy a C628 just to learn about it....  So if anyone has one handy could they look at it and tell me:

1. Do the trucks pivot in their geometric center or at the middle (off-center) axle?
2. Can the trucks used with the frames from other Atlas locos?  If so, which ones?   For example, I think an SD9 or SD35 might be close to the right truck centers for a proper RSD12 - if we are referring to geometric centers.

Also - anyone have pointers to accurate scale drawings of an RSD12?    The "dieselshop.us" web site data is unreliable at best.
http://www.thedieselshop.us/DataRSD12.HTML

So, this is going off of memory, but:

1:  Off-center
2:  They drop into a few other six axle frames, as I recall, such as the Trainmaster.  However, with some mods, they can be made to work in a B23-7 mechanism, which, as I recall, will get you close to the correct truck spacing.

[AlbertSpor]

George,
They pivot off of the center axle. Check here for photos and a link to how to fit them into an 8-40B chassis, https://www.therailwire.net/forum/index.php?topic=36934.msg441044#msg441044
I was thinking about doing the same thing, but into the GP-35 chassis, which gets you close to the correct wheelbase, but you have the wider Kato designed chassis to deal with. Also there are drawings and an article in the September 1987 Mainline Modeler magazine, about the RSD-12.
PM me if you would like to borrow any of these to play around with, your Railwire address is close to my work address.
Albert

[nickelplate759]

So, I've finally got adhesion promoter.   I'm going to paint the frame and handrails yellow now.   The ends, side sills and railing are supposed to be yellow, the rest (including handrail posts) should be black.  I can mask the walkways and steps but don't think it's practical to mask off the handrail posts.

So here're a question - I can see two ways to attempt this:

1. spray the frame ends and sides yellow, but neither the handrails nor posts.  Hand paint the handrails yellow. 
2. spray the frame ends, sides, handrails and posts yellow.  Hand paint the posts black.

The frame & railings will NOT be on the engine when I paint them.   I'm leaning to method 2 - anyone have any experience to share?

[nickelplate759]

another question - anyone got a Tru-Color paint suggestion for replacing the Testors Model Master "Signal Insignia Yellow"?