PRR N2 Steam Locomotive Build

[nscaleSPF2]

So here is the plan.

Start with a Bachmann 2-10-2:



Lots of nice detail on the running gear, the mechanism runs pretty smoothly, even better with a decent decoder.

Add a Superturbine boiler shell from Jason Smith:



Lots of really nice detail here, also.  And a good fit on the Bachmann mechanism.  I think that this is actually a shell for the M class of locomotive, but my measurements indicate that the boilers for the M and the N classes were practically the same.

We are trying to recreate an N2:



According to Wikipedia,
"The Pennsylvania Railroad's class N2sa comprised rebuilds to PRR practice of the 130 USRA Heavy Santa Fe steam locomotives the railroad received under the auspices of the United States Railroad Administration, the nationalized central control of the nation's railroads during World War I. These locomotives, as received, were classified N2s. Rebuilds began from 1923 and all locomotives were rebuilt, classified N2sa after the rebuild. They received a Belpaire firebox, the PRR-standard smokebox front, a raised headlight following PRR practice, and the bell moved from smokebox front to boiler top. Brakemen's "doghouse" shacks were built on the rear tender decks.

Their assignments were primarily in PRR Lines West (of Pittsburgh), especially after the introduction of the I1s decapods. Both these and the PRR-designed N1s 2-10-2s were primarily used to haul iron ore from the ports on the Great Lakes and coal towards them, at a slow drag freight maximum speed of 35 miles per hour (56 km/h). The arrival of larger power such as the J1 shifted the N2sa locomotives to more secondary roles."

Maybe some of you spf's out there can verify the accuracy of the above.

Anyway, here is the result, just before the engine heads to the paint shop:





There is nothing special about the tender.  The Bachmann one seems to be the correct length, and even has trucks that are similar to the prototype's.

Enjoy the photos.  Comments are welcome, as always.

[randgust]

That's cool.   I was going to ask the obvious questions on where those were used but you covered that.   

Note that the photo has one pulling what appears to be a troop train in WWII - the hospital car or diner in the center is a giveaway.

Did the original Bachmann one have a metal shell?  That's the only concern I'd have about this project - trying to get the weight up to get any real tractive effort out of it.     My GHQ conversion out of an Kato Mike (L1) is an absolute beast with the traction tire, but that's with a heavy cast-metal boiler shell.

[CodyO]

Did you solder the plumbing on the engineers side?

Looks awesome and like a very quick project.
 
what did you use to cut out your styrene block?and did you drill it out to put the wire into it?

[pjm20]

Very nice, I am planning to do the same to my Walthers Proto decapod.

[mmagliaro]

Well, here's my ex slobbering PRR freak two cents...

I'm always loathe to criticize when somebody is obviously a skilled modeler and is doing a nice job, but there
are some big proportional problems with using the Bachman 2-10-2, at least to my eye.

That chassis has small, widely-spaced drivers.  Aren't those about 53"?  They should be 63" for a PRR N2.
And while the M1's overall boiler dimensions are close to the N2, that big Belpaire firebox from the M1
extends about 4 feet too far forward for an N2.  If you could pull the shoulders of it back, it would look a lot more correct.

I try not to be a rivet counter with things like this because the overall goal is to get the related proportions
right and have it look "Pennsy".   The above 2 things are big proportional issues.

Excuse my "wet rag".  You're doing a nice job.
Those cooling lines soldered to hanger strips - really nice work there.
I just think that some of proportions between an M1 and N2, and that Bachmann chassis, are just not right.

[peteski]

I also feel funny criticizing this type of model (since I have never built anything like this), but sine nobody mentioned it yet, I will.  The shell seems to sit way too high over the chassis. And by quite a bit. I thought it was just a test photo and the shell was not fully seated on the chassis but when I mentioned it going to the paint shop I think this is its final location.  It just doesn't look right in my eyes.

[Dave V]

I also feel funny criticizing this type of model (since I have never built anything like this), but sine nobody mentioned it yet, I will.  The shell seems to sit way too high over the chassis. And by quite a bit. I thought it was just a test photo and the shell was not fully seated on the chassis but when I mentioned it going to the paint shop I think this is its final location.  It just doesn't look right in my eyes.

In fairness, having done a few similar bashes myself, this seems to almost always be the case.  My H10 and M1 bashes both sat too high.  I never was able to get them low enough for my liking.  The GHQ L1 conversion, OTOH, sat correctly out of the box.

[Kiasutha]

Part of it may be because as Max said, the drivers are too small.
The Pennsy loco did have 63" drivers; while the light usra had 57".
I've no idea what size the bachmann ones actually scale out at, but they look small.
Maybe there'd be room to use the drivers from a consol or kato "Mike- they'd be about right.
No criticism implied here...
 

[mmagliaro]

Part of it may be because as Max said, the drivers are too small.
The Pennsy loco did have 63" drivers; while the light usra had 57".
I've no idea what size the bachmann ones actually scale out at, but they look small.
Maybe there'd be room to use the drivers from a consol or kato "Mike- they'd be about right.
No criticism implied here...

I agree, the small drivers accentuate the look of the boiler sitting too high.
The USRA light had 57", but I looked up some old review threads on the Bachmann engine, and in there
Victor measured the actual Bachmann drivers to more like 53".  It wasn't clear if that includes flanges,
but I'll assume it doesn't.  With the flanges, they might be closer to 57".  The problem is that visually from
the side, the flanges won't show enough to make the wheels look bigger or closer together.
It might help when that white striping is removed from the drivers.

EDIT:
I am less concerned about the boiler sitting high, because things like that can usually be fixed.  If you are really
determined, you can always mill or file that frame down, or ream out the inside of the shell wherever possible.
The driver size and firebox size are the two things that concern me most here, because there is little you can do about them once you commit to using those parts.

[victor miranda]

I am pretty sure the 8.25mm diameter is tread.  (52 inches)

the flanges add a little more than a mm to that.  (makes it 58 inches)

I recall  24 thousands but I can't find a measurement.

(so I think the drivers represent a 55 inch driver)

victor

[nscaleSPF2]

Wow, I did not expect such a large response to the original post.  Thank you all for your comments.

Before I respond, I need to explain a few things.

This post was not intended to be a "look at what I did, isn't this great" post, rather it falls in the category "look at the dumba$$ thing I did, hope that you don't make the same mistake".  A lot of my recent posts fall in the second category.

First, the boiler sits at exactly the correct height.  I spent a lot of time getting this right.  It appears to sit high because the drivers are undersized, and I think that this is accentuated by the white wall drivers.  (For a visual comparison, check out Nate Goodman's recent post of his Con-Cor 2-10-2 in "Let's see the Steam").

Already well into this build, I noticed that there was something not-quite-right with the drivers.  I had already checked the spacing between the drivers, which is close to the prototype's, and the drivers are as close together as they can be without the flanges rubbing on each other.  So do not blame Bachmann for the 53 inch drivers.  Blame the size of the flanges required for N scale.  The Bachmann drivers for their 2-8-0 are 60 inches in diameter, which is almost perfect, but there is no way that they would fit without a new frame, and a stretched wheelbase.

So I was faced with three alternatives.  Stop the build and put the parts in my junk drawer, make a new frame, or continue with the build and learn to live with the result.  I chose the third alternative.

As far as issues with the boiler casting itself, there are more things wrong with it than the length of the firebox, Max.  The running boards have several up-and-down jogs that are not present in the prototype (on both sides of the boiler) and none of the N2 prototypes had 2 air compressors on the fireman's side.  I considered stripping off all the running boards and the details located below them, to make them closer to the N2 prototype's.  But given the issue with the drivers, I decided to live with all of the discrepancies, paint them black, and hope that they won't be too noticeable.  As far as shortening the firebox, to be honest I did not notice this until Max pointed it out.  But I know that I would make a total mess of that if I tried to fix it.

Now on to the other posts:

Did the original Bachmann one have a metal shell?  That's the only concern I'd have about this project - trying to get the weight up to get any real tractive effort out of it.     My GHQ conversion out of an Kato Mike (L1) is an absolute beast with the traction tire, but that's with a heavy cast-metal boiler shell.

Yes, the Bachmann boiler is made of metal, but the superturbine casting has plenty of room inside for additional weight.  The Bachmann mechanism does have 4 traction tires, so I don't anticipate any pulling problems, especially since my layout does not have any grades.

Did you solder the plumbing on the engineers side?
 
what did you use to cut out your styrene block?and did you drill it out to put the wire into it?

The trick with the plumbing is to use phosphor-bronze wire, instead of brass.  It's much stiffer and does not deform as easily.

Start with a strip of .040 by .040 styrene.  Drill a hole for the wire perpendicular to the strip.  Trim the end of the strip.  Now drill the other hole in the end of the strip.  Finally, trim the cube off of the strip.  It's a good idea to put a wire thru the strip before you trim the cube off.  Otherwise it will disappear on your work surface, never to be seen again.

Hope this helps.

[mmagliaro]

Jim, you are one stand-up guy.
And for the record, I did notice the walkways, but I figured I was already giving you a hard enough time 

Since you obviously understand the approximations of using the Bachmann engine, I will just
wish you good luck on your project and watch as it progresses.  I do agree that getting rid of the white
walls will help.  I would reconsider shaving off the walkways and putting correct ones on, along with
the correct compressor location and piping.    I think it would improve the model enough to be worth doing.

That large Z-shaped jacketed steam line running up
the left side on the smokebox is a dead "M1a" giveaway spotting mark.  So I would be sure to get rid of that (but I'm sure you knew that).

[peteski]

First, the boiler sits at exactly the correct height.  I spent a lot of time getting this right.  It appears to sit high because the drivers are undersized, and I think that this is accentuated by the white wall drivers.  (For a visual comparison, check out Nate Goodman's recent post of his Con-Cor 2-10-2 in "Let's see the Steam").

Well then...maybe another approach other than accuracy should be invoked?

Instead of trying to make the model accurate (which would naturally give it perfect proportions to look "right") you might consider to dispensing with the accuracy and try to make the model to look "right" with what you have.

As-is, compared to the prototype photos, the model just don't look "right". Like I said, the shell look like it sits way too high over the loco's frame. IMO, if you were to lower the shell down on the mechanism that might hide or minimize the wrong look of the smaller drivers. and give the morel the right look.    Mind you, this is only a speculation on my part, but if I was building that model that's what I would try.

[victor miranda]

.....dunno....

I think I'd lower the boiler a bit.

the reason for that is to reduce the spacing from the drivers to the boiler
where one can see the proportions are a little off.

another way to say that is that the area from driver tops to boiler is easy to see.

the overall height can drop a 1/16 inch and few will be able to tell.
(this is a generic comment ...)

the drivers are smaller than they should be by about half the 1/16th I just mentioned

so lower the shell about 1mm and it should look a lot better as a model.

victor

[mmagliaro]

the drivers are smaller than they should be by about half the 1/16th I just mentioned

so lower the shell about 1mm and it should look a lot better as a model.

victor

A good observation, Victor, and it made me think.   Half that 1/16th... thats about .030"...
I wonder how wide those white stripes are.  I bet they are at least that wide.  They have that
"American Flyer" look.  So maybe removing  the stripes will make a huge difference to how those drivers look.

Because of that...
nscaleSPF2:  Perhaps it would be a good idea to take that striping off now instead of later. 
It could affect the whole way you (and we) look at the model and how you decide (or not) to lower or adjust it to improve its proportions.