MRL 132 GP9 in Proto:48
Jan 29, 2014 22:35:16 GMT -5
Colin 't Hart, brgp302300, and 1 more like this
Post by ednadolski on Jan 29, 2014 22:35:16 GMT -5
Hello Detailers! Here is my project featuring a build of a Red Caboose GP9 in O scale, with Proto:48 wheels & dimensions. I had this kit from a few years back and had put it away due to problems with the drive train. Recently however I re-discovered it, hiding among a variety of other stored items. I couldn't resist opening it up and looking it over, and after doing so I realized that it was just too nice a model to let it sit forever in some box. So I decided to have a go at fixing up the drive issues and finishing the model.
For the drive train, I was (finally!) able to find the parts that I needed online, and I ended up replacing all the chain and sprockets with better quality components. I also ended up changing the gear ratios from approx. 1:1 to something like 2.5:1, since my intended use is low-speed operation. It took some effort but I finally got the unit running, and I am very pleased with its low speed performance.
I installed the Proto:48 wheelsets, which are as close to a true prototype profile as can be made for a model. The gauge is also a correct scale 56.5" instead of the too-wide traditional scale 60" (1.25 actual inches) that is historically known as "O gauge". For this model I also installed the kit that narrows the trucks to prototype width. I was surprised at the difference in appearance that those few scale inches made. For all-wheel electrical pickup, I fabricated some phosphor-bronze strips and installed them to contact the back sides of the wheels. You can see the additional wires in some of the pics below.
The model kit originally came with a plastic frame, but I'm building it with the optional machined brass frame. This is much more sturdy and adds weight. I did have to slightly modify the frame to allow for the larger sprockets that I installed in the drive. I also installed some additional styrene strips to represent the underframe structural components.
For a prototype, I settled on the Montana Rail Link. This railroad still has a number of GP9 units in service today, and it is an interesting sight to see these next to the MRL's brand-new SD70Aces. Besides, I like blue, LOL... I'm building this unit as MRL 132, which you can see here at this link and at this link.
The MRL GP9's have the 'chop nose', so that will be one of the key modifications I will be making to the kit. Anyways, that's enough words for now. I'm planning to update this thread as progress continues, in the meantime here are some of my initial pics (including a comparison shot next to a typical N-scale loco).
Drive train with brass frame:
Initial assembly of drive train, trucks, motor, and DCC decoder:
Shell test-fitted onto the frame:
Closeup of one of the brass trucks. The suspension on this thing really works!
Hope you enjoy this!
Ed
For the drive train, I was (finally!) able to find the parts that I needed online, and I ended up replacing all the chain and sprockets with better quality components. I also ended up changing the gear ratios from approx. 1:1 to something like 2.5:1, since my intended use is low-speed operation. It took some effort but I finally got the unit running, and I am very pleased with its low speed performance.
I installed the Proto:48 wheelsets, which are as close to a true prototype profile as can be made for a model. The gauge is also a correct scale 56.5" instead of the too-wide traditional scale 60" (1.25 actual inches) that is historically known as "O gauge". For this model I also installed the kit that narrows the trucks to prototype width. I was surprised at the difference in appearance that those few scale inches made. For all-wheel electrical pickup, I fabricated some phosphor-bronze strips and installed them to contact the back sides of the wheels. You can see the additional wires in some of the pics below.
The model kit originally came with a plastic frame, but I'm building it with the optional machined brass frame. This is much more sturdy and adds weight. I did have to slightly modify the frame to allow for the larger sprockets that I installed in the drive. I also installed some additional styrene strips to represent the underframe structural components.
For a prototype, I settled on the Montana Rail Link. This railroad still has a number of GP9 units in service today, and it is an interesting sight to see these next to the MRL's brand-new SD70Aces. Besides, I like blue, LOL... I'm building this unit as MRL 132, which you can see here at this link and at this link.
The MRL GP9's have the 'chop nose', so that will be one of the key modifications I will be making to the kit. Anyways, that's enough words for now. I'm planning to update this thread as progress continues, in the meantime here are some of my initial pics (including a comparison shot next to a typical N-scale loco).
Drive train with brass frame:
Initial assembly of drive train, trucks, motor, and DCC decoder:
Shell test-fitted onto the frame:
Closeup of one of the brass trucks. The suspension on this thing really works!
Hope you enjoy this!
Ed