Cladding

Cylinder block cladding.

I am using 24 swg brass fo the cladding and to make the cladding for the cylinder blocks I first made a paper template by cutting the paper to width and then wrapping the paper over the cylinder block and marking out the fixing holes and drain cock holes by rubbing a pecil over the paper which leaves an impression of where the holes are. The paper is then glued to the brass sheet already cut to width and the holes drilled.

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Paper template stuck to the brass sheet.

Two cut outs are required one at the bottom to clear the draincock operating lever and one at the top to clear the steam pipe flange. The top cut out in the template has been marked but not yet cut.

Once all the holes are drilled the brass sheet has to be bent to fit the curves of the block. I used a steel bar of similar diameter to put the curves in by hand pressure. Then its a case of offering up the cladding and checking the hole positions and the curves. So it’s on and off like the proverbial yo-yo ( I know that’s up and down) until a good fit is obtained and the holes all lined up with a little bit if filing here and there.

Once happy with the fit the cladding is still a bit springy so once all the fixing screws were in place for the bottom part of the cladding I used a gentle flame to reduce the springiness and get the cladding to lay flat on the front of the block. Then fitted the remaining screws and also reduced the springing at the top curve.

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The fitted cladding

All fixing screws have washers and are small head 8 BA.

Once done the draincocks are fitted and secured in place with thread locker.

Before fitting them I painted the cladding. The brass was first etch primed followed by a grey primer. Then satin black top coat was applied. This is same process used for all other painted areas but this time a problem arose as the black wrinkled. So I rubbed the cladding down applied another coat of grey primer and tried again. It still wrinkled but not as much. A bit of research on the web provided advice that wrinkling is usually due to the underlying layers of paint still releasing solvent from the drying process. I had left 24 hrs between coates which I thought sufficent but obviously not. So I repeated the process leaving it longer and achieved a better result although there was some evidence of wrinkling but in areas that were not visible. I left it at that.

Another cladding task that can be done with progress as it is the cover around the steam pipe exiting from the smoke box.

An awkward shape to determin so a template was made from card.

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How to make the template though? Well I used plastacine. I moulded plastacine around the pipe and shaped it the smoke box and to give the angled shape down to the running board. With this mould to hand I carefully rolled the mould onto card tracing the line as I went.. The card was then cut and with a few minor adjustments to true it up on the job used to cut the brass sheet.

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The card was glued to the brass sheet to enable the sheet to be cut and filed to the card template and trial fitted as seen above.

Satisfied that the cover fitted OK the flanges were cut by marking the sheet from the now available cover and soft soldered in place.

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Soft solderinga flange in place

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The finished article.

The cover is held in place with three 12 BA cheese head screws tapped into the running board. There is no fixing to the smoke box.

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The finished fitted cover

Before finally fitting the cover the pipe was lagged with 1/8″ thick  sheet lagging wrapped around and a small bit of wool lagging needed around the steam oil lubrication non return valve.