Best Of Polar Express build

[peteski]

Excellent John!  So what did you end up using with the flickering LED? 500 ohm resistor and/or hooked it up directly to the rectifier?

[Lemosteam]

Peteski, I used one of the 560ohm resistors you specified (the one just past the rectifier in your circuit), hard wired to the rectifier as you suggested.  That Flickering LED gets hot so I'm a little worried about the roof.  I may end up moving it back to the other side of the board and drilling a hole thru the board to use the board as a heat shield.as a heat shield.   I left the fire atop the led for a while and the heat does not seem to affect it. 

[peteski]

Hmmm.  The flickering LED should not get warm at all under normal operation.  If you measure the voltage across, is it more that 3V?  If it is then it is getting too much voltage.  The other possibility is that it got partially damaged by your previous attempts to power it up (but it is still good enough to seem to be working).  Do you have another one to try?

The problem with powering the fflicker LED with a variable source of voltage (like a DC throttle) is that the LED has a fairly narrow range of operating voltage. The white LEDs are much more flexible. They emit good amount of light from less than 1mA of current to their maximum current.  Since current through the flicker-free circuit is directly dependent on the input voltage, the white LEDs have much greater range of operation at all throttle settings.

The better solution for the flicker LED would be to power it from a 3V voltage regulator, but that introduces another set of issues and increases parts count.  That is why working with DCC makes lighting effects so much easier to implement.

[GN Fan]

What are you doing for decals?

I have been thinking about doing one of these, I'm sure that yours will be much better, since this would be my first car bashes.  But if you are getting decals printed commercially I'd be in for a set.

Tom Todd

[Lemosteam]

GN Fan, Microscale makes a North Pole express set, 60-1433, that you must piece together, thankfully full words.  My assumption is they could not obtain a license. Don't sell yourself short, these are my first car cut ups!

Peteski, yes I have several. It is funny how the voltage at the 1.2k resistors varies very little through the full throttle range.

It did fry this time after it got hot enough that it melted the solder at the resistor and positive lead.

I am at a loss now.  There is room on the board as this board does not have all of the capacitors.  I would like the flicker led in the near middle of the board.  Ideas? Parts? Ve decided I really want this feature.

[peteski]

GN Fan, Microscale makes a North Pole express set, 60-1433, that you must piece together, thankfully full words.  My assumption is they could not obtain a license. Don't sell yourself short, these are my first car cut ups!

Peteski, yes I have several. It is funny how the voltage at the 1.2k resistors varies very little through the full throttle range.

It did fry this time after it got hot enough that it melted the solder at the resistor and positive lead.

I am at a loss now.  There is room on the board as this board does not have all of the capacitors.  I would like the flicker led in the near middle of the board.  Ideas? Parts? Ve decided I really want this feature.

So, I'll email you directly with the options. There are dozens of 3V regulators at Digikey I'll just have to pick one.. .

[Lemosteam]

Thank you Peteski!  In the meantime:

Installment eleven... Decals and dullcoat complete:

The baggage car:

 

The Combine:



The optional coach sleeper, the hobo will likely end up on this car.:

 

The passenger car:

 

The diner car, or Hot Chocolate car:



The observation car:

 

And finally, the tender:

 

I decided to place the decals low on the cars, like the book edit, movie..

Next I will be finishing the observation deck detailing and adding the figures.

[chicken45]

Looks like an early P70! 

[Jeff AKA St0rm]

Looks great!!! and it should be done in time for christmas 2015 

[VonRyan]

John, seriously, only U.S. uses knuckles (well some Japanese Kato models too) - rest of the world still uses Rapidos. To this day! All my European prototype models are Rapido-equipped and there are no problems. Like I said - successfully used in N scale since the 60s. 

I figured that since this is a fixed (and fantasy) consist (and you are on a deadline), Rapidos would work just fine.  Call me silly. 

The pivoting action on the MT heavyweight couplers is totally unintended. Think about it - if the coupler box rotates then the automatic coupling/uncoupling no longer works. The couplers will just be floppy and won't line up in the car's center line.

I think that I saw bunch of Red Caboose couplers in stock at M B Klein recently.

Chinese N-scale uses an MT-comparable one-piece knuckle coupler.

[peteski]

Chinese N-scale uses an MT-comparable one-piece knuckle coupler.

I did not know that.   I never seen an N scale model of a Chinese prototype railroad subject.  I learned something new.  Sounds like those are similar to the Red Caboose couplers, since usually 1-piece knuckle couplers can only be uncoupled by lifting up one car's end above the adjacent car's coupler.  Unless the couplers themselves can be be tilted up (like Rapidos) for automatic uncoupling.

[nkalanaga]

Since MT-clones are now being made in China, I wonder if the Chinese modelers will start using them?

I wonder if the Chinese have any N scale models of their steam locos?  If they were available for export, there might be some interest from North American modelers.

Unrelated, there was once a proposal to drop the old "horn-hook" coupler as the HO train-set standard and switch to Rapidos.  The idea was that Rapidos not only worked better, but were close to HO scale than the horn-hooks, and looked better.  As it is, nothing came of it, and other knuckle couplers became the none-KD standard, just as they seem to have in North American N scale.  It would have been interesting if HO had adopted an N scale coupler.

[Lemosteam]

Polar express elevenpointone

Installment eleven.1.... A revised circuit for my 3D fire.

Here is a very short video if the revised LED placement and 3D fire.

The fire will protrude up through the roof casting and hopefully tall enough yo pierce above where the hobo will be sitting. A longer one may be required, but oh well.

Up next finishing the porch...

[craigolio1]

That is so cool.

[Lemosteam]

First, thanks craigolio!  I'm glad you like it!

Installment twelve...It's all about the children, Billy the lonely boy, Hero Girl, and Hero Boy, as the Wikipedia cast info identifies them.

I bought a Prieser "Nun with children" figure set, separated some figures sculpted a long robe for Hero Boy and painted them in approximate colors. They will appear on the observation deck as they were in the movie when singing "When Christmas Comes to Town":

 

After adding glass to the back wall and adding the railing, here they are, installed on the observation deck:



In an attempt to recreate this scene:



Next some touch ups, couplers and roof install for the observation car.  Interior will have to come later as I am fresh out of seats.