Tuesday, August 10, 2021

HO scale 3025 Build Process

    Hello everyone, First I must apologize for the lack of posting here. As I have stated before I have been working primarily on a history project on the various types of equipment found on the Valley Railroad. What started as a simple series of articles has, for the better, turned into a full fledge book. I will go into more details about this at a later time but please now that more Model trains and 3d modeling will be coming in the near future. But as for today I thought it was finally time to update you all on my HO scale Valley 3025 project.


    I’ve mentioned before that this was my first true scratch building and semi rivet counter project. There are so many aspects of the hobby that I learned from this and am very happy with the outcome, but I know there is always room for improvement.

    As stated before, I started with a stock Bachmann 2-8-2 SY class Mikado, Susquehanna No. 142, to be exact. This is the best place to start if you would like to follow my process as about 60% of the work has been done by Bachmann. However, the biggest issue is what the other 40% entails. When Bachmann created their SY model they used the Chinese locomotives as the prototypes. Meaning that they are in their original configurations with the engineer on the left and firemen on the right; opposite what is standard here in the United States. This would also include their model of No. 142 as it is a glorified repaint of the base model for the American markets. The issue with this is that the actual 142 and 3025 were modified at Tangshan to be right hand drive before coming state side. Meaning that certain appliances and controls on the model are on the wrong side!!! So, in order to match the porotype 3025 I would need to revers the details, a task easier said than done.

     First step disassemble the model and start to remove details.


This included the reverser, air pumps, automatic lubricator, what I believe is the throttle piping and headlight. (I can be 100 % wrong on these items names) Be careful to not loose screws and parts during this process and hopefully you don’t have the same issue I did and find that screws are missing from your model you bought as “Used but never opened”. eBay can be cruel sometimes.

Here is a comparison of what I removed from each side of the boiler compared to a stock 142.




The next step was to make major modifications to the running board as the air pumps pass through them. The issue here is that the running board is cast metal piece that can be very fragile. I accidentally bend mine during the cutting process and needed to straighten it out before continuing. Two cuts are needed here one is simple as it cutting off the slim section of running board for the stock pumps. The harder side is cutting a duplicate square cut out to match the other sides dimensions. These cuts were done with a razer saw, hobby knife and pliers.  After light sanding it was a simple matter of gluing them onto the opposite sides. Where there were gaps, I used strips of styrene 0.040. The annoying part here was that the running board has built in diamond plate some of which was sanded off curing the cutting. I later replaced this with a diamond plate 3d decal I found on eBay. More of this is detailed in my previous post.




With the major cutting done I moved on to body filling and final sanding. For this I used Tamiya Surface putty. This helped fill in small gaps and divest where parts were removed. These areas were sanded using varying degrees of fine sanding sticks I got from Hobby Lobby for cheap.

Following this I placed all of the metal components, (Frame, Wheels, Running Board, etc.) into a plastic tub filled with Super Clean Degreaser. I know this may seem odd but it was suggested online by a fellow modeler and tested it on a Tyco model to great effect. While these parts were soaking over night, I moved onto 3d modeling.

In addition to the new reverser listed in my previous post I also updated my 3D models of 3025’s cab and tender. Both have been available on my shapeways store for a few years now and are based on the original drawings used to create the actual items. The newer versions (Which will be uploaded soon) are more detailed and better fit the Bachmann model. (I guess there is a slight difference in sizes between Bachmann’s model and the real engines dimensions. Benefit of being able to measure the real engine for reference.)

The newest model to be created was the entire smokebox and headlight. I knew I as going to have to design a NH style headlight to fit the model but didn’t expect to remodel the entire smokebox as well. The short answer is that the stock smokebox was just too different that I needed to create it to satisfy my need to make it look accurate. (The smoke box will be available online as well soon.

While the parts were printing, I moved back to the parts soaking. 24 hours later the paint was peeling off, remaining paint was gently removed with a toothbrush. (Remember to wear appropriate safety equipment.)


With the old paint removed and the 3d parts cured it was time for primer and test fitting. I used Tamiya fine spray primer and quickly assembled the major parts. 3025 was looking more and more like its prototype.


This was soon followed with a coat of Tru-Color Engine Black. And graphite for the smoke box.

With the engine shaping up it was time to focus on the tender. The process was very similar to the cab and smokebox. Design, print, primer and paint. Hardest part was fishing the new LED headlight through the body and gluing the light in place. The tender body snaps on and off with built in clips so its very easy to access the electronics inside.


The rest is simple reassembly, super detail items and decals. All which can be seen in my Facebook group photos.  There is still some detail work to complete and replacement screws to find but overall, it has been a really enjoyable project and can wait to bring it to a few friend’s layouts as a special “guest power” maybe once I’m really happy with it I will bring it down to the Valley to pose with its1:1 scale inspiration.