Crafting CPR’s ‘Sandford Fleming’ Theatre Car in N Scale

[peteski]

That's too bad Dwight.  I had my share of projects going "south" on me, but I still haven't left the hobby. Hang in there!

Looks like the clear window area in the theater section is intact. That is a good thing.

You can likely hold the pieces together and flow some liquid cement in the joint (from the inside). Tamiya cement comes with a finely pointed brush in the cap.   Just don't knock the bottle over for more carnage!    You will have to sand (and maybe even smooth/fill) the seam in the roof, then repaint it.  The re-glued clear window area will have scar in it. You will likely have to cut out the area, then just glue a piece of clear inside the car's body to replace the cut out section. That will likely be the easiest part of the repair.

[sirenwerks]

The tilted saucer-like item has me puzzled.  And in that first photo in the above post, it looks like the two cars preceding Sandford Fleming each have the very same thing on their roofs.  Beats me!

They're rainwater catchment devices. I know this beyond a shadow of a doubt.

[Dwight in Toronto]

They're rainwater catchment devices. I know this beyond a shadow of a doubt.

 
On one shoulder sits a tiny gremlin telling me sirenworks is pulling a fast one; on the other sits his counterpart reminding me of my naivety by suggesting who am I to question! 

[davefoxx]

On one shoulder sits a tiny gremlin telling me sirenworks is pulling a fast one; on the other sits his counterpart reminding me of my naivety by suggesting who am I to question! 

Well, if you believe that, then you should know that this VIA car has a brick chimney, visible in the following pic.  As you can imagine, it’s got a fully functional Rumford firebox, complete with a colonial-style mantel, and perfect for those Christmas Eves when St. Nicholas needs a convenient ingress/egress. 



DFF

[Dwight in Toronto]

Thanks Dave - I was kinda playing along with the ‘it’s a bird bath’ claim.  And the pic you posted is indeed the Sandford Fleming coach I’m modeling, in one of its earlier incarnations.


I shoved discouragement aside, bellied up to the bar, and ‘got on with’ the repair attempt.   

I held the fracture in place with small pieces of masking tape on the inside surface of the shell, then dabbed miniscule beads of thin styrene solvent along the inside seam.
 
An hour later, I masked where required, and airbrushed the roof section.  Then airbrushed it again.  And again.  Six times.  The exterior seam remains slightly visible, but I think I’m going to live with that.  I could have attempted more intensive cosmetic surgery with Tamiya putty and lengthy rounds of sanding and smoothing, but there was the chance of that going from bad to worse.  Better to leave well enough alone:




I’m lucky that it was a clean, two-piece break (rather than multiple fragments).
Also - hard to believe, but the separation in the clear glazing segment managed to avoid  transgressing through any of the window openings … that part of the break is hidden by the car side.  Thanks for small miracles!

I’m going to leave it as is for now, and proceed with the build.  There’s always a chance that other aspects could head south.  If the remaining work goes to plan, I can always revisit that slight imperfection in the roof. 

Thanks for the encouragement guys.

[davefoxx]

That’s great that it went back together that well with no obvious damage in the windows.  But, I would suggest that you reconsider and take @John’s and @peteski’s recommendations to hit that crack on the roof with Tamiya Putty and repaint.

DFF

[sirenwerks]

Thanks for the encouragement guys.

Glad you caught my sarcasm. As much as TRW has a significant knowledge base, it has a significant amount of leg pulling and tongues stuck in cheeks; and a double dose of subtlety at times that creates undergarments to twist. Don't be a twist - always err on the side of humor.

[Dwight in Toronto]

That’s great that it went back together that well with no obvious damage in the windows.  But, I would suggest that you reconsider and take @John’s and @peteski’s recommendations to hit that crack on the roof with Tamiya Putty and repaint.

DFF

Thanks Dave.  I’ve used Tamiya putty (the white stuff) often enough, but I tend to look at that as a last resort.  I have had good results with it, and some not-so-good.  For me, it’s reminiscent of doing my own body filler repairs, long ago, on my then-25 year old ‘78 Camaro.  No matter how meticulous I was with the finishing, the paint always revealed less-than-perfect results (my bodyman brother-in-law would make things right afterwards!).  I do genuinely welcome the peer pressure, but as I mentioned above, I think I’ll leave well enough alone, at least until I see how well the rest of the build progresses.

Plugging ahead, I fabricated tiny lense housings for the upper lamp assemblies on the rear face of the car, attached them to the fascia above the big picture window, then drilled light openings penetrating through to the coach interior:




I used Bondic UV-curable clear resin to make the lenses, and lightly dabbed red and green Sharpie on what I assume are some sort of classification lights, or maybe just end-of-train markers (?).

The odd little triangle piece above the big window is my attempt at a light delivery tube.  I don’t know if this is going to work.  The idea is that it will be affixed on the inside of the fascia that it is perched on in the pic. 

Here is how I made it, starting off with a piece of Kato transparent sprue:




I drilled a hole in the apex to accomodate a white 0402 LED.  I filed the sprue piece to have a thinner profile, then glued two strips of black 0.01” styrene to the inner edges of the “V”.  I then glued two triangle pieces of the same black styrene to the top and bottom, sandwiching the clear plastic light pipe in between.  I then ‘polished’ the light pipe ends using 1200 grit wet sandpaper. 

So, what we have are a light pipe source on the right and left edges of the triangle piece, and a smaller, blacked-out triangular cavity in the interior of the assembly (apologies for the crappy photo, but hopefully it shows what I’m trying to explain):




Out of curiosity, I slipped the headlight LED from one of my locos into the hole I had drilled in the apex of the triangle, and was encouraged to see that the light pipe effect seemed promising:




So, referring back to the first pic in this series, my idea is that the two light pipe faces will snug up behind the red-&-green lense assemblies, and that the LED at the apex of the triangle will illuminate them.  Now, that smaller triangular cavity that exists inside of the two light pipe arms, which is lined on all sides with black styrene … I intend to slip a second white 0402 LED into this cavity, and hope that it will illuminate the other two lamps. 

Both LED’s should be controllable through function mapping on the ESU light strip.  Anyways, that’s the plan.  As I say, no idea if this will work.  Stay tuned!

[Dwight in Toronto]

Quick update.  The diy light pipe approach did not work.  Details follow.

First, I spent a bit of time familiarizing myself with the ESU digital light strip on LokProgrammer.  It really is a nifty little piece of electronic engineering; worth every penny.

I then cut down the ESU strip to fit the length of the car, replaced the two factory-wired “rear light” red LED’s with one of my prewired 0402 white LED’s, and soldered a second 0402 to the “front light” pads on the board.

Usually, I find that the 0402 LED’s that I’ve been using are shockingly bright, and I’ve been equipping them with 8K+ resistance to dim them down.  Having soldered them onto the ESU light board, I found them to be nowhere near as bright as I was hoping, and needed them to be, for the light pipe application. 

I think I have to abandon the idea of using one LED for the right & left red/green markers, and another for the two rear spotlights.  Might have to use four separate LED’s instead.

Back to the drawing board.

[peteski]

Can you tell what value resistor ESU has in the red LED circuit?  Looks like I should buy one of those DCC LEDs strips to figure out how everything is laid out.  It is possible that the common positive voltage on that board is 5.3V (not 12v) like ESU has done on some of the LokSound decoders.

[Dwight in Toronto]

Can you tell what value resistor ESU has in the red LED circuit?  Looks like I should buy one of those DCC LEDs strips to figure out how everything is laid out.  It is possible that the common positive voltage on that board is 5.3V (not 12v) like ESU has done on some of the LokSound decoders.

As soon as I saw the dimmer-than-expected LED output, I tried to discern what resistors they might have used.  There are two components adjacent to the red LED solder pads that sure LOOK like smd resistors, but they are labeled something like “O1C”, which means nothing to me!
The coach lighting LED’s each have an “810” resistor on them.  There’s one that says 4700, and another larger smd resistor of 1000.  There is a variable resistor/pot to adjust brightness of all the LED’s, but I didn’t try tweaking that (the car lighting LED’s didn’t need to be any brighter).

Sorry Pete, but that’s about all I can tell you.  And yes, I think you would be interested in doing an autopsy on one of these strips!

[peteski]

Dwight, If you want to get into a bit of reverse engineering, try to measure resistance across all those resistors you mentioned. You might have to customize your multimeter's probes. You could clip some jumper wires with alligator clips and on the other end of the jumpers clip some thin stiff wire. Something like piece of paper clip, or even better straight pins (as those are thin and have sharp points).  Then use those to probe the resistors to measure their resistance.  Of course with the power off.  The readings of the resistors in the circuit will likely be slightly off, but likely very close to the actual resistance.

Since I do this fairly often I made my own micro-probes using sewing needles glued in pieces of styrene tube. For wire leads I used ESU decoder wire, and on the other end I have alligator clips to clip them to standard size test lead probes,  but in your case you could make some ad-hoc ones like I described above.


Here are my probes. If you follow the thin red wire to the upper right corner of the photo you will see where the red alligator clip is clipped to my multimeter's red probe. Same with the black probe (but the black alligator clip is barely visible).

I'll buy one of those lighting strips next time I order some decoders (which should be fairly soon).

[Dwight in Toronto]

Peteski, instead of micro-probing the resistors on the ESU light strip, I focused on getting track power into the shell.

I tried the earlier suggestion of simply soldering ESU decoder wire to the brass tips of the Kato wheelset pickup posts.  This worked great at the head end of the car, where the wires came straight up, vertically through the floor, and where it was easy to slip on small pieces of heat shrink tubing as solder joint reinforcements. 

The tail end of the car had to be done differently.  The tiered seating platforms meant that the track power wires couldn’t intrude vertically into the shell, and had to be run horizontally instead.  I soldered the wires to the pickup posts in a horizontal orientation, affixed them to the bottom of the frame, and ran them to the front end of the coach. 

With the wired trucks in place, I latched the car to a loco and subjected it to repetitive loops around my “S” curve-equipped test oval.  Although the coach was negotiating the track effortlessly, it was obvious that even the minimal flexing of the decoder wire at the solder joints on the rear truck would eventually result in separation. 

So, I ended up using the Kato phosphor bronze contact strips for rear truck pickup.  The first pic is a top-view, the second photo is from the side:






I attached a small piece of PC perf board to the interior floor at the head end of the car.  This serves as a junction point for the right (red) and left (black) truck-mounted wires, with an additional set of red and black wires feeding track power to the ESU light strip.  I included a yellow decoder wire with a 570 ohm smd resistor, just in case I end up installing rear backup lamps using one of the extra LED outputs on the light strip.

Once I figure out how I want to retain the light strip within the shell, I’ll be able to connect it to track power, and then solder up the four LED’s for the tail-end lamps.

[peteski]

Looks like the Napoleon Hat trucks are there to stay?

[Dwight in Toronto]

Looks like the Napoleon Hat trucks are there to stay?

Not necessarily …  as I mentioned in our earlier discussion, I’ll get the more appropriate trucks the next time I have to order something from Kato.  They have a minimum shipping fee of $20 for Canadian customers, so I’m content with what I’ve got for the foreseeable future!