Opportunity to learn some hands on engineering at the residential Missenden Abbey Engineering Weekend. There was a huge mix of activities broken out into about 8 different areas ranging from paint spraying to metal work. I took the opportunity to work on the Midland Spinner frame which I am very happy with progress so far, definitely got to break in quite a bit of the equipment I have been collecting (think I took everything but the kitchen sink).
We even saw some snow!
I have reprinted the plans of St Pancras in my final quest of making St Pancras, now in 2mm scale. Here are the first sample outputs of the drawings which are taken from the plans and then re-drawn in Adobe Illustrator and then fiddled about with in InkScape via svg and dxf formats for cutting – all very complicated!
These flat structures will have a number of detail added to them by the way of low resolution printing I have been testing.
St Pancras has to have something running on it, and here is what I am working on, I done a number of 3d prints which really pushed the boundaries but really a heavier material is what will make this work. The resin is probably just too light to pull any sort of loads out of the station.
So sticking with 3d printing, the boiler here is printed in wax and then cast in brass. However this is very light and probably still not very practical. The result looks amazing though. Close inspection however shows a lot of dimples where the brass is polished, this wouldn’t paint nicely, if you look on the inside you’ll see that the unpolished area is very rough. I have filed it flat and will smooth it off for painting, but still not there in a mass production perspective of having a dozen of these locos.
You’ll note my workbench has seen computers disappear and give way to a whole suit of watchmaking tools, now to learn how to use them!
If you have been following this post you’d know that I built a 3d model to extract the CNC paths from to cut my metal pieces from. Well I was curious how far I could push the 3d boundary and decided to make a specific model to incorporate this pushing of the bar. This resulted in using extremely tight tolerances and the agency writing back to me telling me they didn’t think it was possible, I asked them to try and it was 95% successful, with some further refinements required.
I also sent off a series of wheel sets indifferent sizes, again because the tolerances were so tight I wondered what ones would come back in pieces, I am glad to say the correct scale wheels were fabricated, but without some bevels and so I will try to incorporate them into the next version.
I am very pleased with the results of both parts. The loco itself in my opinion is ready to paint with no further working. The wheels need taking down a fraction.
However I do wonder if this is a way forward for mass production (well multiple production) or whether it is just too light in comparison to a metal frame. I think if I went this way I would add a lot more detail now I can see the limitations in person.
After joining the 2mm finescale association and the quest to have a locomotive from the 1890’s that used to run on St Pancras (I am sure you have seen the St Pancras obsession on this blog) This is my first attempt at building a 2mm scale model.
I’ve taken a reasonably modern approach to prototyping, checking the size via a 3d print after designing the model in a 3d Cad programme from plans. From there I have used my CNC machine to cut the shapes from 0.25mm brass sheet. The precision has come out particularly well as you can see.
In addition to this I have also had a go at turning some of the large drive wheels (15mm) on the Harrison M300 Lathe and also hand turned some chimneys using a smaller jewellery lathe with some success.
In my quest to build a scale model of St Pancras, which set out as an experiment in 3d prototyping I have taken a trip to the Midland Study Centre and found a treasure trove of information, including some of the original plans and even my favourite photograph of all time – a fairground opposite St Pancras Station, found randomly whilst looking for the Midland Spinner drawings! I wonder if the fairground will make it into the final model 🙂
I had read a lot about Tim Watson via google and some of the remarkable models he has scratch built in 2mm scale.
I was lucky enough to meet him at the Copenhagen Fields Layout on the MRC stand at Alexandra Palace this year. I then had the wonderful opportunity to meet Tim at the Model Railway Club just by Kings Cross/St Pancras where he showed me the Midland Spinner he hand built some 30 years ago, and that I hope to attempt to build myself. Tim has been invaluable to learning some of the techniques needed for the construction of these models and also has a passion that is infective.