#scratchbuild

I've always liked the EMD SW series diesels, mainly due to the way they look. So, about a year ago, I bought a Proto 2000 SW9 with a view to making an On30 version of this diesel. Recently, I got around to doing it.

I started with the donor locomotive, as well as some cabs left over from previous projects. I went with the (maroon) one made from plastic, as the texture and window shapes on the 3D printed one weren't suitable.

After marking out the footplate, I used the original model's footplate to trace out where the gap would need to be cut to accommodate the hood.

After removing the hood from the original cab of the model, I glued it in place. I had to file the cut hole slightly, but it fit in place.

I added some styrene strips along the sides, to hold the body slightly higher than it had been originally.

With that done, I added the pilots and a bit of an overhang.

My next step was to install the electronics. With the speaker suspended over the rear truck, I was able to put the TSU-1100 and keepalive on top of it. I did have to widen the hole at the rear to accommodate this, but that will be covered by the cab.

With that done, I added some footplate details and the cab itself. I then test-fit it. After this, I raised the body by another 1mm, to allow a bit more space for the electronics.

The cab I recycled had a flattened lead weight glued to the roof which I couldn't remove, so I needed to account for this. The wires for the rear headlight actually run through this weight.

With that done, the model was ready to paint. On my previous On30 diesels, I usually painted the body in Tamiya 'Hull Red', with a black footplate. This time, however, I decided to do something a bit different.

I'd painted a few N scale diesels in a custom livery for my N scale 'Inglenook Harbour' shelf layout:

These had the blue and grey painted on, with decal lining separating the two colours. I decided to do a similar livery for the On30 SW9.

After priming the body, I masked off the bits that I wanted to remain red.

I then airbrushed Tamiya 'NATO Black', which is really a very dark grey, over the model. After removing the masking tape, I was left with red panels around the side. I then put black paint on the radiator grilles, to add some depth.

After a coat of lacquer, I applied the decals. I used Microscale HO scale 4" wide white striping, and 'Block Gothic' lettering. The usual 'Railroad Roman' that I've used on my other locomotives didn't seem to fit, as this is a more modern diesel.

Thank you for asking.

The first thing I'd say is to make sure the locomotive runs well. That it has a good chassis and smooth motion. I've had a couple where I didn't, so they ended up looking okay but running poorly.

It helps to have a good idea of where the project is going. Unlike a 3D model on a computer, making a scale model doesn't have an 'undo' function. Parts can be removed, but they'll leave glue marks. These can be removed, but it'll be tricky. Knowing where you're going also saves time and money, as you can focus just on what you need.

For example, my latest build (which I haven't posted here yet) was to make a 'On30 SW9'. With this clear goal, I was able to take a HO model of an SW9, identify what I needed to do to make it an On30 model (new cab & running board) and figure out the steps needed from there.

Having the right tools for the job is important, as well. It's important to keep your hobby knives sharp, as a dull blade will wander and not cut properly. Also, keep a first-aid kit nearby (don't ask 🙂).

Using the right glue for your materials is important as well. PVA/wood glue is good for wood, cardboard and paper. It also dries clear, so I usually use it to stick window glazing in place. Plastic weld cement works on plastic only. Cyanoacrylate adhesive, or CA, is good for sticking anything to anything (including fingers). However, it'll turn clear parts cloudy, hence why I use PVA for those instead. (It also makes them easier to replace if they get cracked or marked.)

It's worth buying some copper craft wire, also known as 'beading wire'. I've made dozens of handrails, grab irons and other bits from it over the years. It's easily found on sites like eBay, and I keep a few different thicknesses of it in stock.

If you're using DCC, make sure to leave space for the electronics - decoder, speaker and keepalive module (if applicable). Also consider if you're going to put lights in the model and where they're going to go.