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Showing posts from January, 2008

Tender Body

The original drawings showed what I think is the Hawksworth tender - I've previously made one in 5 in gauge, and thought the Collett tender would make an interesting change. It has a couple of major challenges - the top of the sides are flared, and also the rear corners of the tand are very rounded, so a tricky compound curve is created where they meet. I took the basic dimentions from the drawings, and scaled the Collet specifics from a couple of photographs. The fact that the major lines of the tender matched up with the profile of the cab gave me some useful reference points. Then there's a raised extension which fits on top. I left a tab which I curved to match the lower part of the tender, and riveted and soldered the two together. The other tricky bit was the rivets -there are several hunders of them, and they're very prominent. My solution was to make the tender tank out of thinner brass than usual -about 22 gauge. (Another reason for this was that I had a couple

Tender 1

The frames were already cut out, saving a bit of sawing. I checked that all dimensions were correct, and cut out the buffer beam and drag beam, from angle section. It never seems to be truely square, which shows up on the insides, when the angle fixings are mounted. So I lightly milled them all over, which got rid of the mill scale at the same time. Also the angle sections to lock it all together. I clamped the angle iron in place, and drilled through from the fames. Only then, I marked of the length of these pieces, taking the dimension from the frames rather than from the drawings - at least this way, they all fit accurately. I worked on a surface table, checking that all was square as I went along. For the horn blocks, I milled the mounting surfaces to size, and riveted them to the frames, slightly overlapping the horn openings. then milled the horn gaps to size. This made sure that the horn slots were accurate and truly square. If I'd milled them completely to size before fitti

Painting

I recently read the book 'How (not) to paint a locomotive' by Christopher Vine (ISBN: 9780955335907). It's full of useful information, and a council of perfection. I read a lot of the things I'd tried when painting the A3, and although I stopped short of what he'd done, I came to many of the same conclusions. I sprayed using a Pasche internal mixing air brush, using automotive type paints (NOT two-pack cyano acrylics, which absolutely need an external air fed mask. I used water based paints (sounds odd, but I'm told are the replacement for cellulose paints) , thinned with cellulose thinners. I started a very light coat of etch primer, just a token rub down, then grey primer. Finally, a few light coats of gloss. Once its cured - at least a week - I flatted down the surface with 1200 grit wet and dry paper. I then used cutting paste in two grades, and was amazed at the quality of finish I achieved. I've heard aerosol spray paints being recommended. I have tri