Evening All...

This blog post appears after a long line of evenings trying to work out why my 3D designs were not being accepted to print on Shapeways.. The answer it turns out was simple, and familiar to anybody cursed with a bucket with a hole in it. In short, you need to ensure that the 3D model is 'manifold', in other words, does not contain the kind of tiny holes which are easy to miss when you have a model with several hundred, or thousands of tiny lines and surfaces combining to make something resembling your prototype.

All of my designs are done in Google Sketchup, and I have made a little discovery which helps in finding these rogue holes. In the 'view' menu, under 'edge styles' DESELECT 'edges' and instead SELECT 'profiles'. This then hides the 'wireframe' of spidery thin lines that define the shape of the object, leaving only a shaded mass of stuff, with thick lines tracing sharp edges. Much like in the case of my Class 139 here:

Look closely at the side of the cab, and you see a pointed blue triangle behind the lower light cluster, under the main headlamps. This was a hole. After several frustrating evenings trying to upload the model it now works, and will soon be printed hopefully in time for the model to debut on Wyre Forest MRC's Kinlet Wharf at the DEMU Showcase event in Burton.

You will notice that it is now a hollow model, which will require a little extra work, to hopefully good effect, cutting out and installing glazing. The odd thing with 3D printing is that by deleting holes where the windows ought to be, and chipping away material from inside the cab, the cost has gone down (to about £18 for a print) despite the relative complexity of the design going up. With a bit more of a 'crash diet' I could probably reduce wall thicknesses to the extent that the model became printable for less than a tenner. (In the most expensive 'Frosted Ultra Detail' plastic)

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Thoughts on scales in and around 2mm/ft.

There has been some lively debate around RMWeb on scales and standards for models of this size..

..the above Class 139 is designed to '1/148th but then stretched a little to fit the Kato chassis' scale...

With some very sensible proposals put forward (this is a personal preference, but very sensible in my book equates to if it looks right.....ish ). As far as I can tell the modelling world has four scales for British outline '2mm' modelling:

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a) Bog standard N gauge.

Or is it? Take a look at...

http://www.rmweb.co....y/page__st__150

...which has its beginnings as a few ovals of plain Peco track, and becomes something genuinely rather wonderful. I put a link here in case bloggers missed it among the layout threads. If you have yet to see the story in full, pour yourself a strong cup of tea or a tall vintage cocktail and tune in to the broadcasts!

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b ) .What I am going to call 'EEN gauge' (confusingly, pronounced the same as 'N gauge') where 2mm FS Easitrack is used beneath modern RTR N gauge stock to great effect. This could be done with careful interweaving with standard Peco points, or with handbuilt 'hybrid' points as in TomE's Ropley.

PS... (Easitrack-Enhanced-Ngauge)

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c) Full 2mm FS trackwork and points, with heavily modified N gauge stock.

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d) Absolute full on 2mm FS. (I have seen it done and remain generally and respectfully in awe!)

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I was going to try to pigeon hole myself into one of these, but in truth... I aspire to vague modelling ambitions ambling and bodging my way in amongst all four.

Latest news from Victoria Bridge, I have been building more layers of varnish in the river itself, including a number of eels approximated with stripes of silver paint, I'm not sure they are strictly 2mm/ft.. unless maybe they are substantial conger eels!