Noob Scratch Builder Attempts N Box Cab Loco

[Dwight in Toronto]

Having hung out at TRW for a couple of years now, I found that I was getting increasingly inspired and encouraged by watching talented craftsmen create remarkable models from raw materials.

Over the years, I’ve done some freight car mods, kit-bash add-ons, loco detailing etc, but I had never tackled the scratch build of a loco shell.  It was time to give it a shot.

A few months ago, I ordered a few things from Plaza Japan, and while browsing their site, I came across a small Kato 2-axle powered chassis (#11-108, used in their Steeple Cab series).  I had no idea what I’d use it for, but at only $19 I couldn’t resist:



When the urge to scratch up something took hold, I thought this little chassis would serve as a good introductory base upon which to start building.  I also thought that a small box cab loco would be a relatively simple structure on which to cut my teeth.  Here’s a small sample of models that I found online, from which I scoured an array of design concepts and ideas:








My first step was to equip the chassis with an ESU LokPilot decoder (no sound on this model!).
This included fabrication of a small pc board to serve as an anchor point for the track and motor wires, as well as three 8K ohm resistors for LED’s:




A trip to my LHS equipped me with a variety of Evergreen styrene.  After a few hastily-drawn plans and sketches, I started by fabricating a base “foundation” using .04” styrene - ie - a substructure upon which to glue the more refined cab walls and other features:

[peteski]

A few months ago, I ordered a few things from Plaza Japan, and while browsing their site, I came across a small Kato 4-axle powered chassis (#11-108, used in their Steeple Cab series).  I had no idea what I’d use it for, but at only $19 I couldn’t resist:

Yes, those "critters" are very handy for all sorts of bashes. Especially the new version with equalized suspension and coreless motor. They are also quite a bargain for what you get. @Chris333 likes them.  They are only 2-axle (4 wheels), not 4-axle. 

[Dwight in Toronto]

I laid out the four walls on a single piece of .02” styrene, and hand-scribed the representation of board-&-batten siding.  I also tried a few techniques to simulate wood grain, and found that a combination of wire brushes and sand papers did a pretty good job. 

After marking up window and door locations, I started to cut out the openings:




I do not have 3D print capability, nor any automated cutter device … solely a variety of Xacto blades, Dremel kit, jewellers files, miniature belt sander, pin vice and the like.  For the openings, I found that drilling the corners with a #78 bit in the pin vice provided handy access points in which to introduce the knife blades.  Slow, steady blade work, followed by careful filing, did a fairly good job of squaring up corners etc. 

Throughout this entire build thread, I implore my fellow enthusiasts to PLEASE chime in with faster/easier/more accurate/more efficient ways of doing the tasks and steps that I tackled.
This entire project is an exercise in bringing our motto to bear … “Better modeling through peer pressure” !

[Chris333]

Oddly I never bought one of those 4 wheel chassis the whole time I was in N scale until basically right before they changed the design. And I bought it just to see if it would fit a body I made. The new version of the chassis shown here is way better.


But lets talk about that ConCor ruler 

[Dwight in Toronto]

Chris333 - lol - what’s wrong with my ConCor ruler? (50 cents train show find!).

I finished up the cutouts for windows and doors, and then had a shot at making the doors and window frames out of .01” styrene.  Since I wanted to spray dullcote BEFORE the window glazing went in, I had to first airbrush the cab walls and then apply a few decals (the road number is my birthday - 2356 … Feb 3 1956).  I also had a shot at fabricating the front headlight housing, as well as an engine radiator shroud, complete with fine-mesh metal grill, and two air grates for mounting into the side walls:




Not knowing any better, here’s a demonstration of how I did the window frames.  I pre-fabbed the required number of slightly over-sized “L” segments, then fine-tuned them, simply by progressively nipping/filing/sanding & trying until they snugged in with a friction-fit.  When all was good, a drop of watery Testors adhesive did its job through capillary action:



Again, I had no preconceived notions about how best to make window frames and doors.  I hope the masters amongst us will advise on alternate/better approaches.

Glazing. 
I was worried that the adhesive used to affix clear styrene to the backs of the window frames might cause paint-bleed staining.  As an experiment, I made the window frames extend very slightly beyond the interior surface of the cab walls, such that the glazing, when glued, was actually laying on a bit of a “standoff”, slightly distant to/set back from, the interior wall surface. 
I also glued in narrow .01” ‘shims’ between each window to help ensure that the glazing was set slightly back from the inside wall surface.  I’ve tried to convey this methodology with the following pic:



I hope this makes some sense, because it definitely worked … there was no paint bleed whatsoever.  Feedback time … I’d love to hear from others about window, glazing, and door fabrication techniques.

[Dwight in Toronto]

A big step was separating the four wall segments, and aligning/affixing them with adhesive on the supportive ‘foundation’ piece.  A little bit of Tamiya white putty helped to ensure seamless joints at the four corners (I quickly learned how nice this putty is to use, if one first dilutes it either with Testors adhesive, or Mr.Hobby paint thinner).

However, the main point of the following pic is to demonstrate how I tackled the fabrication of the curved rooftop.  I first made a paper template, then cut out the roof using .02” styrene.  But how to form the curve?  Some time ago, many of us watched a video where someone made a highway bus from pvc plastic pipe.  I remember how this fellow used a Bic lighter to gently sag-&-bend various shapes.  So, I attached the styrene blank to an old pill bottle with double sided tape, and proceeded to heat-&-press the soft plastic to conform to the pill bottle curve:

[Dwight in Toronto]

A little bit of followup filing and sanding resulted in a pretty good fit. 

My next goal was to make the roof look like old oak or teak planks.  I happened to have some very thin real wood veneer, that was originally wrapped around a fine cigar in a stoppered glass tube … my long-departed dad gave it to me some 20 years ago (after he had burned the cigar).  Aside - anyone know why cigars are wrapped in wood veneer, and what kind of wood it might be?




Again, please comment on alternative ways of heat-forming styrene plastic!  Heat gun?  Low temp oven?  I’m sure there are better ways than what I did here!

I scored the veneer to simulate wood planks, then attached it to the styrene substrate with double sided tape:



A view of the rear - note the backup lamp housing formed from a very short piece of brass tube:




My next challenge was how to attach the roof to the cab body, but retain the ability to remove it?
I need to be able to remove the roof so as to facilitate access to the cab interior, in order to be able to properly position the LED lighting (this will become clearer near the end of the build).

I ended up creating two styrene tabs, one on each upper edge of the cab walls, and two corresponding slot assemblies glued to the underside of the roof (tabs & slots indicated with red arrows):



The roof is simply dropped in place:




Then pushed rearward until the stops bottom-out:




So far, so good, I think!

[Dwight in Toronto]

Next, I thought it was time to flesh out a subframe around the lower half of the loco chassis.

Here I used .04” strips, and then some Evergreen channel for the lowermost skirt:




Here’s how the cab fits over the chassis and snugs up to the subframe.  Note that I’ve had a shot at fabricating a few roof details, and simply plopped them in place for a quick look-see:




I had a bit of fun with all these bits and pieces.  The star of the show was my cordless drill, which I adapted as a poor-man’s lathe.  First, I had a go at shaping some styrene rod into compressed air cylinders, an exhaust pipe, and a small horn.  Encouraged by this outcome, I likewise used the drill to form a bell from some small brass tube.  A few jewellers files and sanding sticks did a pretty good job, but I’d love some input on alternative approaches!


I spent a bit of time cutting out rectangular openings in the subframe, and then fitting suspension hardware where the axles are located.  Also cobbled together some compressed air reservoirs and hung them on the centre portion of the subframe.  This was followed by a quick spray of Mr. Hobby black:




I aged the wood on the roof with a thin wash of white and gray paint, followed by light sanding.
I also painted a thin wash of aluminum on some of the roof components, so as to give them a bit more of a metalized/steel look, and added brass strapping to anchor the exhaust pipe to the roof.
I know, I know - brass would never have been used … it would have been steel strapping.  But I’m really liking the look of real brass alongside the lavender paint job, so I’ve decided that railings etc are not going to be painted - they will all remain pure brass.

[dem34]

Think its an unwritten rule that everyone's first Scratch bash is a 23 tonner/Steam dummy inspired boxcab.

[peteski]

That's pretty darn impressive Dwight, and also creative.  I like your window frame method, roof retaining tabs, and heat forming the roof. You keep asking for better methods of what you are doing, but your methods are quite good already.  The window frames method is new to me, and I like it.  Easy and simple.

Your model  looks very good, even a bit whimsical!

The other comment I have is that I'm not a fan of seeing 1:1 scale wood(grain) used to represent 1:160 scale wood.   The other thing is that as I see it, I would have stopped on painted plastic roof.  In real life roof needs to be waterproof. I don't think you would see a natural color wood used for a vehicle roof.  It would have likely been either sealed with tar, tar paper, or covered with something solid.  If you left the roof as (painted) bare plastic would likely be a better representation of 1:1 roof.  Of course someone will post a photo of  a 1:1 vehicle with bare wood roof!   

[Dwight in Toronto]

Thanks guys.  I chuckled at how a box cab seems to be everyone’s first scratch attempt … makes sense, since it’s just so nice and ‘boxy’!  And Peter, I appreciate the praise, and I particularly welcome the commentary regarding prototypical practice. 

I started out with the intention of replicating a sheet metal roof.  I even went so far as to purchase one of those spiked wheel tools from a local fabric store to try impressing a rivet pattern in the .01” styrene (they had a $5 tool, and a $22 version - I opted for the pricey one).  I could not get an acceptable simulation of rivets, so decided to try the more offbeat wooden roof.

Hmmm, I was just thinking - I should have taken pics of the things I tried that did NOT work, and posted them as well.  After all, my prime objective in sharing the build here on TRW is to emphasize new learning and draw out better ways of doing things.  Next time will feature failures as well!

[Dwight in Toronto]

Diverted my attention to beefing up the front end of the box cab.

Added a bit of styrene strip and channel around the Kato horizontal grid bars, which included a narrow shelf effect right across the lowermost front edge.  I don’t know why, but a lot of the sample models I studied have this just-above-the-rails cow-catcher sort of thingy.

I also added the same wooden plank effect for the flooring of the front “porch”, as was used on the roof:

[Dwight in Toronto]

Added a front guard-rail using .02” brass wire, and an “old hand” taking a well-earned break to have a bit of a rest and a wee look around.

Also added a few hand grabs using .012” brass wire:

[Ed Kapuscinski]

DUDE! This is sick. I love it!

Especially that roof forming trick. Brilliant.

[peteski]

More added details look great, but the 0.020" handrails?
I thought after your initial attempt of using such thick rod for N scale handrails, then finding that much thinner rods are readily available, you swore off ever using 0.020" for handrails.  That is 3.1" diameter in 1:1!    The grabs on the corners of the cab look closer to scale.