Best Of Scratchbuild Project - CC&F Twin Trailer Flat Car

[BCR 570]

For most of us attempting to model a prototype railway as closely as possible, we often have to resort to kitbashing for some pieces of equipment which are not likely to ever be available commercially.  However, there are some cars for which there is nothing close enough to use as a starting point.  In this case, scratchbuilding is the only viable option.

Such is the case with the British Columbia Railway's fleet of twin trailer flat cars.  During the 1970s approximately 13 per cent of the railway's trailer traffic went to Dawson Creek, so I am going to need several of these.

The first five purpose-built cars were received from Canadian Car & Foundry in December 1961 and were the first twin 40' trailer flat cars in Canada.  They served the railway until 1994.

I have some dimensions from the railway's 1976 Revenue Car Catalogue, and I was able to refer to a pair of HO Scale models built years ago by PGE modeller Bill Hewlett.  Additional reference photographs were sourced from fellow PGE-BCR modellers.

To examine the feasability of attempting a scratchbuild of these cars in N Scale, I decided to try my hand at a pair of test sections.  These were intended to help determine the specific sizes of styrene to be used, and to work out the optimum order of assembly.  Specifically, I wanted to see if I could duplicate the actual construction arrangements of the prototype without having to make too many compromises.  In other words, would I be able to build a highly accurate model from raw materials?

In these photographs, the lower section is a slice out of the middle of the car showing the full depth centre sills, a diaphragm and several cross-ties.  The upper section includes a tapered section of the centre sills, a bolster and end coupler pocket for the purpose of working out the truck and coupler requirements.

The first two photographs illustrate the underside of the car with supporting diaphragm and cross-ties, and also the bolster and coupler pocket arrangement:






The next photograph shows the top side of the car with the running plates either side of the centre sills:




These end views offer a cross-section view of the cars:






Several important lessons were learned during this process.  I invested some time learning how to measure, mark and cut out parts accurately for a precise fit with each other.  I also made some changes in sizes of material between the first and second test sections, and I revised the order of assembly.

I believe that this process will help me to build a much better model.  I invite you to follow along as I attempt my first scratchbuild of a revenue freight car.  Constructive criticism, suggestions, and words of encouragement are all welcome!


Tim

[James Costello]

Wow, looks amazing Tim, very impressive!

Any photos of the prototype?

[VGN50]

Tim,
Nice approach to the project.  Consider this a word of encouragement.
Mark

[TiVoPrince]

Question
With the open nature of the centrebeam do you have a plan to add weight?  I have a similar project in mind but cannot figure a way to get enough weight to track reliably.  I'm interested in what solution you may have up your sleeve...

[Hyperion]

Question
With the open nature of the centrebeam do you have a plan to add weight?  I have a similar project in mind but cannot figure a way to get enough weight to track reliably.  I'm interested in what solution you may have up your sleeve...

Looks like there's quite a bit of space right between those two I-beam center sills that could be packed full.

[lock4244]

Geez, Tim... your test looks flawless. Do you walk on water, too? 

I've been, off and on, pondering how to obtain models of CP's 81' COFC flats, so this will be of great interest as they present a similar dilemma being rather open cars.

[BCR 570]

James:

Prototype photographs coming soon - just waiting for permission to post them online.


Others:

My plan is to have some custom weights machined in tungsten.  I figure I can get slightly better than half an ounce inside the centre sill, which is not enough, but it is better than lead.


Tim

[Iain]

James:

Prototype photographs coming soon - just waiting for permission to post them online.


Others:

My plan is to have some custom weights machined in tungsten.  I figure I can get slightly better than half an ounce inside the centre sill, which is not enough, but it is better than lead.


Tim

Have you considered doing the centerbeam of brass?  When I built all my logging flats, I used brass for the weight, even though it was slightly harder to work.

[Sokramiketes]

An additional benefit to brass structural shapes, besides weight and durability, is that their cross sections are typically thinner than styrene.  Maybe it's not an issue, as I'm not familar with the prototype, but if the styrene looks thick, it might be an option.

[wazzou]

Didn't I read somewhere that there was no substitute for Skibbe? 

[BCR 570]

The styrene shapes I am using are actually fairly close to prototypical dimensions.  I did fatten up the centre sill web for longitudinal rigidity, and because the thickness will not be visible when completed.

Using brass structural shapes is an intriguing idea but I have no experience working with it.  Getting square accurate cuts is a little more challenging, and I do not know if it could be glued or would have to be soldered together.  I like working with the plastic cement because you have working time to make sure every joint is square and solid.


Tim

[Iain]

CA works on brass.  Now's the time to get acquainted with it, you won't gain experience if you don't try it.

[Hyperion]

CA works to varying extent with brass.  Different brands seem to work to very differing degrees.  I've had really good luck with the E-Z Bond lineup that Kleins carries.  I'm sure soldering would help, but seeing that I'm deplorable at it, I've not really tried it.  I would think in conjunction with the glue to hold the work in place would be great, but not sure how the CA would holdup next to all that heat.

[Iain]

When soldering brass bits, I'll tack together with glue first, then solder.  Don't glue the brass to plastic and expect to be able to solder it to something else.

[TrainCat2]

CA works on brass.  Now's the time to get acquainted with it, you won't gain experience if you don't try it.

I would not use CA in this application, nor any other that involved extruded brass shapes. You would have to clean AND etch the surfaces before CA could get a bite on the metal. Rolled sheet is fine. The Brite Dip chemical that is used to keep tarnish to a minimum actually helps CA adhesion. Shapes sold by K&S (or by Special Shapes) will not bond properly with the natural oxidation the extruded surface develops.