The smokebox
With Bridget both the steam supply and (obviously) the steam exhaust pass through the smokebox so it is necessary to get the smokebox in the right position before the appropriate steam plumbing can be put in place.
The steam supply will come from the superheater tubes into the steam column, a vertical gunmetal manifold that passes through the bottom on the smokebox and then out to the cylinder steam chests. The lubricator injects steam oil into the very bottom of this column so that it is carried into the cylinders. This is a reasonably straightforward machining job with some copper pipework. The supply pipes have to bend through a pretty sharp right angle as they go over the frames and on to the top of the cylinder. I found this pretty hard to do well and, in the end, made a deep groove in a piece of round bar and worked it round as best I could with lots of annealing.
The exhaust pipes are much more of a challenge because they have to be silver soldered together while in place between the cylinders and the smokebox in order to have any chance of fitting and sealing. More of this later.
The core part of the smokebox is a piece of 6 inch diameter steel tube and I was pleased to discover that this is easily obtainable from my local metal supplier. Photograph 27 shows this piece of pipe cleaned up, machined to length and with the steam exhaust and flange fitted. I also drilled the rather large hole on the top for the chimney. Obviously, you can’t use a pillar drill to drill these. I mounted the piece horizontally on a boring table on the lathe, drilled each hole and then bored out the chimney hole to the required 40mm diameter.
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Denne historien er fra 4627-utgaven av Model Engineer.
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WORKSHOP TIP - Boring Eccentrics
I am making a 1 inch Minnie traction engine and have arrived at the machining of the eccentric straps.
Wenford A 7¼ Inch Gauge 2-4-0 Beattie Well Tank
The stage has now been reached where the well tank body can be completed but beforehand there are some internal details to add.
Vertical Boiler Locomotives
Vertical Boiler Locomotives
Union Nuts, and How to Make Them
These are quite different from those commercially available and are made from copper
SHOWCASE Paul's Engine
One day my son Paul came to me and asked if we could make something in my workshop, so that he could learn engineering processes.
CLUB NEWS
My secret’s out!
Building Dancer - The Boiler
Dancer needed a boiler that would be somewhat larger than the size permitted under the Model Engineering exemptions in the New Zealand regulations.
An Inverted ‘Ross Yoke' Watercooled Stirling Engine
As with all my hot air engines they are cheap to build, mostly from scrap
A Draught Proposal
A Draught Proposal
A Boiler Feed Pump
A Boiler Feed Pump