5" gauge Kozo Hiraoka Shay

A few pictures showing work done on the Shay. This was the engine as it arrived

This was the state of one of the port faces.

Piston, crosshead and a bottom cover. The steam oil had been introduced into the flow immediately above the manifold branch to number two cylinder. The other two must have been oil starved, causing the seizure and the yarn packing to have been eaten.

Replacing bits missing from the backhead and rearranging to steam feed for the gauge glass so that it doesn't come from the manifold.

This is the newly designed oil injection point. It has a snifting valve which wasn't originally provided. The oil is fed through a 0.5mm hole into a venturi. The hole visible in the photo is 1.2mm diameter and a stub with the aforementioned 0.5mm hole carries the oil to the centre of the venturi bore.

This is the lubricator dismantled for inspection and cleaning.

The loco going back together with the new oil supply visible. She has had new pistons and rods, a new regulator needle, the square cylinders have had the corners knocked off and a lot off pins in the valve gear were replaced when it was found they were in fact using a thread as a bearing surface. I have changed all the visible cross point screws in the engine for socket heads. Not prototypical but they look a lot better.

Here new glazing is being fitted to the cab windows after repainting the inside of the cab. The buffer beam red used originally really jarred on my nerves.

The brass collar seen here resting on a drive shaft has been replaced with a smaller diameter one in steel with a bronze thrust washer. The idea is that the materials are more suited to purpose and the smaller diameter collar cannot foul the gear if things come loose.

This strange thing was the start of of a Lima Improved Spark Arresto, which has been added to the diamond stack. I have a copy of the Shay book and put a picture of the Lima stack drawing into CAD and drew the diamond stack fitted to the model. I was pleased it is actually the same shape. I've designed a laser cut frame and it is effective with an 8 hole per mesh on the top. The exhaust comes out of the full area like the big ones and steaming is not impeded.

Lima stack drawing

This is the completed device.

New nameplates to return her to the original name- I don't like ships and locos having name changes. These were CAD models, wax printed and cast in silicon bronze by Mike Jack in Auckland New Zealand. The enamel is a product called Efecolor available from Cookson Gold. Usual disclaimers.

Loco in steam at Ribble valley Live Steamers, Clitheroe. This was before the spark arrestor was made, there is a bit of wood on the fire for photographic effect. The only thing which doesn't work now is the steam pump. Much closer than it was, but no cigar as yet.

Finally a link to a clip on my YouTube channel of Lucie running at RVLS. I know the big ones were slow, but this one certainly isn't. Lucie at RVLS

She is a miniature 50 ton standard gauge loco to Lima code Baluster of about 1920 as near as I can make out.

Fine work! It is very heartening to see a rescuee returned from a sorry state to proper and indeed truer condition.

An impressive run, too - no shortage of steam, and she certainly makes light of what seems a suitably stiff bank for the Pennine foothills (or Oregon forests!). I noticed you'd notched down for it.

The big ones were probably slow because they had to be driven slowly, expected to drag heavy trains along often very indifferent, sometimes temporary, track where galloping along could have proved Very Unwise.

I studied the spark-arrestor drawings and its parts quite carefully. I'd often wondered those characteristic American wood-burner precautions - vital in forests of course - worked: essentially a very simple cyclone, slowing the embers and throwing them sideways out of the exhaust stream. What do the four holes in the bottom of the central tube do, though? On full-size, burning wood, I'd have thought they would soon become buried in ash.

Congratulations Steve, a job well done.

Neil,

Thanks Nigel and Neil.

I don't know what the holes do and I wondered that myself when I first saw the drawing a few weeks ago. Unless they drew the embers back into the system and beat them repeatedly until they were ejected as harmless dust. There was a another design for areas where the fire risk was greater which I've included below.

She's a whole lot of fun to drive though and so much faster than I ever imagined. It is a shame that you only get to hear the engine when you slowly reverse across the traverser back up to the steaming bays at RVLS. Otherwise at 12 beats per revolution it is just a whoosh.

Pictures are of the Radley and Hunter stack with ports for emptying the cinders. I've put a sectioned version on too but that is slightly different in the initial spark diverter. It wouldn't like the oil we throw out of miniatures!

Steve

Re - holes. I think there are two concentric tubes to the funnel. The flue gas with embers goes up the middle and the embers are thrown sideways to fall back between the two tubes. There they either burn to ash which with good wood is light and will not clog like coal ash does. I would expect the design to have tried to arrange that there is a relative vacuum between inner and outer tube such that the ash is sucked back into the main flue.

Nice work. You have the old girl looking good. I saw a few full sized Shays in parks in the Rocky Mountains USA, former logging train engines. Fascinating machines.