During the 1960's and even into the 1970's there were several articles published in Model Railroader and Railroad Model Craftsman about modifications to currently, (at that time), manufactured brass locomotives and to making them into something else that was not available then.  With the advent of improved injection plastic molding other articles appeard for modifications to plastic models.  Some of these modifications are simple and others pretty extreme.  Creaftsman who have the time, sit down, study the prototype and model,  make plans or drawings, study market availability of parts, and then execute a change based on that research of both the prototype and stock model availability.  This usually lead to a hi-bread model that was unique,  looked great, and functioned as well as the original model did, without having to wait for a manufacturer to produce and import it.  For low quantity run models it is not umcommon for a manufacturer to advertise, well in advance, of a model they were/are thinking of building and see how much interest was/is developed.  If the interest was there they made it and if  not, they saved possible lost money and canceled the idea.

Today we see a proliferation of models in diesel and steam made from all kinds of materials, some plastics, others conbinations of plastic and pot metals, and in some rare and expensive cases even brass.  The cost of these models has risen from the under $20 models to at times over a thousand dollars.  Modelers are reluctant to start chopping and modifying a particular model that they put a lot of money into and  represents a sizeable investment.  So what is a modeler to do when he/she wants a specific model of a prototype that is not available.  First research the present and past market for models you desire.  Check specific detail and see what is the closest to what you want.  If you find something close, you may just wish to only repaint and letter it.  For models that are plastic you need to know the properties of the plastic material you are working with.  Check how it  reacts to certain plastic welds, glues, and paints.  The inside of the shell of the model is a good place to test in small areas without damaging the visable exterior.  ALWAYS perform tests FIRST so your not sorry later.  For metal models, brass or pot metal, you must be more of a craftsman and know how to drill, tap, fabricate, solder, sand, smooth, machine, and posess metals and have other craftsman skills. 

Parts availability to make a change much easier can be located in publications such as the Walther's Catalog, in specific manufacturers publications or on line sites, and even on ebay.  You can order specific parts from the manufacturer, through a hobby shop, or try pot luck on eBay.  These detail parts are excellent sources to change the looks of any project and make it look professionally doen, and something you can be proud of .

Where can these skills be developed and research come from.  The National Model Railroad Association, NMRA, is an association which has modelers, a reseach libruary, and decades of data just waiting for you to tap into.  The regional, division, and local groups of NMRA members that get together at National, Regional, and Local conventions where they hold contests and clinics to pass along the "how do you do it knowledge".  Questions should start there and anyone at these convetions will be more than willing to give you the all important hands on information, give you phone numbers for further questions, and will help out in any way available.  In some cases, there are clinics that Master Modelers and others provide training at with the only cost being for materials, which you keep.  Usually a disc or brochure is provided to take home for reference later on.   All these model makers share information and they are good talkers on how to go about your projects.  As mentioned earlier, another great source of information is the NMRA research Libruary at the NMRA headquarters in Chattanooga TN.  They have thousands of pictures, books and magazines with a staff dedicated to finding the information you are looking for.  Give them a call or email them with your desires.  They will get back to you in short order.

I did just that recently with a project. I am going to end up modifying four (4) Pacific Fast Mail (PFM) older brass locomotives into a specific locomotive that I wanted and was never available.  In this example it was only rumored to have been made by United, the builder for PFM, but only sold in Japan.  I have never seen the United model, a photograph of it, or any data referening to it.  If anyone out there has any of that information I would love to see it.  In any case, no commercially available model has been available in the USA. This unusual locomotive is a Whitney Lumber Company Class C Climax #801 Molly-O, manufacturer shop number #1509, built in August of 1920.  As an example, I first gathered as much information and pictures as I could on the prototype and then compare it against the present day models.  The NMRA libruary found two photo's for me, one of the right side and one of the left side.  In this case the prototype locomotive is a three truck Class C Climax.  When comparing the photo's against the present and past models that have been produced we find that the United Built/Pacific Fast Mail Imported, two truck Class C Climax comes the closest.  A critical study of available material and models is important.  You are looking for the easy way out and that is important because it will require the least amount of work, ie; changes, manufacturing of new parts, and refabrication of a current model. 

For your project sit down and study your model and the protype for differences in detail.  Use a pen and paper to note all the small differences in details on the right, left, back, front, top, and if you can see the bottom, that as well.  With any model we find can find several small differences even over the life of the prototype locomotive.  Major differences may include the fuel bunker, stack, and addtional powered center truck.  On my project the fuel bunker of the model locomotive is way to long and has to be shortened.  This will require the frame to be shortened.  PFM imported some nonpowered tenders that one could be simply attached to the back of the unchanged locomotive and simulate a three truck Class C Climax, that is an easy way out.  This tender, fortunately is exactly the same as the Whitney Climax, but unpowered.  Upon examination and study I found that this unpowered tender can use the powered truck that is under the rear of the present locomotive and the side frames from the original tender dummy truck  for the center truck.  Other mall details must be changed, but the proven PFM drive system is left pretty much intact for smooth and uncompulicated operation. 

Now you need to ask yourself a question, can I skillfully work in brass, plastic, or other materials to the point I am not destroying the locomotive?  Do I have the tools and can I manufacture or purchase a center truck and other parts successfully?  Can I make modifications to the superstructure of the model to make it what I want?  If the answer is yes, then by all means start your project, but take it one step at a time, be careful, and by all means don't be in a hurry.  You will find this project a very rewarding and unique experience that has many rewards.  You will learn new skills and satisfaction from a job well done and receive the praise of those who wish they had the courage to do the same.  What about that $300 model you just modified, what will happen to the value of it.  That question is hard to answer, it depends on your skill, the quality of your work, and of course the market at the time of the sale.  Most of the older modified brass models have a history, and in turn their value is in excess of average market value due to the builders skill and efforts, and the desirability of that particular model.  If you feel you did well, enter your project in an NMRA contest.  You may win and that heritage brings added value at time of resale too.  Documentation of your work is important.  Take lots of pictures and notes during the process.  It is nice to look back on as well as remember what you did and if any problems were met and solved.

Presently I am in the process of building four of the Whitney Climax's, two as it was built and delivered to the Whitney Lumber Company, and two as it was after the big Tallimook burn when it was required to be changed to an oil fired locomotive.  I will post pictures of my progress on these models and will probably write an article for publication as well, from the documentation notes.  You should always document your work.  If you have questions please feel free to ask me and I will do my best to answer them.

I look forward to diving into this project, as a hobby, where I can sit and enjoy what I am doing, which is exactly the way you should look at it too.  When it becomes work, it stops being a hobby you enjoy.  Never fear making changes, it only makes the hobby more personal and enjoyable.

As Thoreau once said, " If a man does not keep pace with his companions, perhaps it is because he hears a different drummer.  Let him step to the music which he hears, however measured or far away."  Now you too can act as an individual and not keep pace with the rest of the crowd, strive to accomplish the impossible and you will make it possible.