Bubbly bolster

The wheel plan for 622 requires perfect castings. Unfortunately, every attempt so far using my test molds has resulted in large bubbles. These bubbles are not there when I pour the resin, but seem to be forming during the curing process. According to the Smooth-on website, this could be due to humidity, and I should […]

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First four tyres

The photo above presents the first four Proto:87 tyres to be found among the chips around my lathe.  These are the 30″ pilot wheels, and their brass centres need to have spokes cut in before getting soldered into the tyres. They’re not perfect, but every wheel is better than the last, and I think these […]

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Wheel Progress

Parts for the first wheel rolled off the lathe this week.  The engine truck wheels are only 8 mm in diameter, and have eight spokes.  The spokes themselves are only a couple of millimetres long, and so, I have elected to make these wheels in two parts – a tyre and a centre. I actually […]

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Momentum

I didn’t realize it at the time, but the worst thing about the great flood of 2018 was that it completely destroyed my momentum.  At the end of January, I had finally arrived at a place where I thought I might be able to cut Proto:87 wheels for #622.  I had even cleaned the lathe […]

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Frame pattern for 622

Working fifteen minutes at a go, I’ve finally finished putting together the pattern for the thicker Nickel Silver sheet.  I think if I’d been more cunning, I almost could have fit two whole models on there.  As it is, there will be plenty of leftover etch and there are doubles of all the riskiest parts.  […]

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Mutually Assured Alignment

I’m telling you this because, in a few months, you might be me, and we will want to take advantage of some of the cunning plans that we laid in the summer. We’re going to attempt to fold the crossheads up from etched material.  I’ve put four of them on the etch because there’s loads […]

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Etching pattern begins

As I start work on the pattern for etching, there is good news and bad news. First the good news: it appears that OnShape have improved the compatibility with Inkscape, and so, now I can take flat patterns from OnShape and import them directly into Inkscape without traversing through QCadCam.  Someone is still resizing the […]

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Virtual dry fit for 622

In typical Panglossian fashion today, I uploaded the STL file for 622’s plastic parts to Shapeways.  I might have hit the big “Print” button, if the bounding box hadn’t precluded the use of their highest resolution machine. It’s a good thing I didn’t because the pause gave me an opportunity to assemble all the parts […]

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All the parts that are fit to print

I’m just about ready to upload all the printed parts to Shapeways.  To support some of the more delicate parts for printing, and more importantly for shipping, I added some sprues.  I actually started out making a sprue for all the parts, but then I re-read the pricing guidelines for Shapeways and concluded that this […]

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