Model Railway, Metropolitan Railway

For years I have been a railway modeller, but getting hold of certain models have proven difficult mainly due to them not being made or them not being correct, or just generally not being available.

3D printing is a tool I have used for small replacement parts but I have never used it for printing a large model like for example a coach. I was fortunate to be in London a few years ago to witness a Steam loco and beautiful 100 year old Metropolitan coaches running under ground.

I have wanted a set of these coaches for years, but the only way I can get them was using 3D printing. After year of research trips, research and reading through books I had enough information to start.

• Metropolitan Railway rolling stock - By James R. Snowdon
• Bluebell Railway - Photos, visits, measurements

The Design:
Using the research from books and photos and general measurements, I managed to start creating the models of each coach. The coaches are all the same in terms of dimensions, but there were some small subtle changes to the chassis (types of buffers, couplings ect).
The chassis of the coaches were all made on Google sketchup, a nice easy to use program but it did have it's Limits...
Which I found out when trying to model the body and the wheel sets.
For these because of complex shape and detail we had to use a program called Creo Elements direct modelling express, which is a much more powerful program to use, and will handle the detail and the curves of the body.

I came up with a neat idea to put seating inside which just slots in to the walls which is nice and easy so you can take them out to work inside the model or to add figures.

Material:
We wanted to go down a cheaper material route due to the size and cost of each coach, I have some prototypes printed on a Ultimaker printer which came out pretty well, I decided to go for the SLS Nylon powder route as it was the most cost effective, and using some poly jet printers to do the detailed parts like the wheels sets and other small items.

First print arrives:
I received the first print earlier in the year, and was quite happy with the print and how it had come out, I changed a few things in the design but the general design remained the same.

Over the last few months, I have been completing the other 4 coaches, one of which printed in Resin by SLA, also had a prototype sent by form Labs who wanted to try and print one on their Form1 plus... which looked very good I must say.

Being a modeller I have now painted up and completed all 4... they are an attractive set, which work and run very well, and also get a great deal of interest.