Use these links to jump to the section you are interested in on this page :-
Making the Regulator Gland Making the Wet Header Manifold Fitting the Dome bushOr try one of the other pages on building Spencer :-
Machining the Driving and Coupled Wheels
Spencer Start page, frames, Axle boxes, painting wheels
I made the regulator bush on the previous page, now I had decided to do all the drilling in one setup I needed to make the regulator gland which bolts into the bush. First thing to do is to clean up a piece of 3/4" Phosphor-Bronze bar. And turn to the classic top-hat shape.
The piece was then drilled and centre drilled. PhBr is not nice to drill. This is hole does not go all the way through as it needs to be tapped to hold the gland nut.
The roughed out gland was then parted off, here's a pic next to the drawing so you can see what I'm aiming for.
I actually finished off the Wet header parts before continuing with the regulator gland but it makes sense to lump all this together. The Gland was drilled to tapping size.
Next the gland inner 40TPI thread was created again using the tail-stock centre as a support.
Next I got to work on the gland nut.
The narrow part was chamfered to make threading easier.
I used a die to make the thread, the die-holder back has pressure applied from the tail-stock barrel to keep it square. Then the part is centre-drilled.
The hole for the regulator shaft is drilled.
Finally the nut is parted off.
Here's the Regulator Bush, Gland and Gland nut prior to dividing
I'm using the same setup as before this time I need 6 equally spaced holes in regulator bush. These are blind holes tapped 10BA
The gland is drilled through clearance size being careful not to hit the chuck. Note The gland nut is in place to keep the crud out of the thread.
Here's them drilled, just need to tap and make the nut an bit nuttier.
Milling the hexagon head on the nut. Note you CANNOT do this with the nut screwed into the gland as the cutter unscrews the nut - luckily not too much damage occurred!
Going back in time slightly I needed the smoke box components which connect to the wet steam pipe from the regulator to the superheater. First up the manifold that connects to the super-heater. The trusty 3/4" PhBr bar was again chucked and cleaned up.
The manifold is has blind hole drilled in it.
Finally it's parted off. Managed to stop my QCTP parting blade to stop slipping. New bolts will cure it.
A similar method was used to make the Wet Steam pipe flange. Though it was threaded before parting off.
This was Lucky as the parting blade had not left a particularly flat edge so a threaded mandrel was quickly made to assist in cleaning up both mating faces.
To align the dividing head I knocked up a couple of centres.
The steam flange needs drilling through clearance for three 6BA bolts.
All three parts were drilled on the same setup, the bush is drilled tapping size.
Bush tapped and trial fit of bolts. Will use stainless for these if I can source them
With all the dividing done it was time to start on the boiler proper again, first job was marking out the position of the holes in the boiler barrel.
Next I needed a way of aligning the milling machine to the centre punched holes. I had some broken milling cutters so it didn't take long to make one into a centre, on the Tool and Cutter grinder.
This 'cutter' can then be used to align the work. Note I had several attempts at clamping the barrel none particularly good.
You can see I've changed the clamping, the Smokebox tube plate and it's wooden former are inside the barrel stopping it from being crushed. You can see the boring head is taking a really wide cut which doesn't help matters. I think I should have made a very narrow trepanning tool to reduce the width of cut to a minimum.
Here's the finished hole with a view of the extra clamping, the whole thing is very precarious and I did feel on the edge of disaster during the cut. And sure enough the hole was too big!
Side view of the clamping
Here you can see there is a bit of a gap between bush and barrel.
The solution was to cut a narrow strip and bash it till it was thin enough to fit between bush and barrel with room for Silver Solder to penetrate.
This took several anneals but no sweat for an experienced copper smith like myself!
Here it is in position. Note the hammer marks
All the parts were cleaned up and pickled.
And assembled with lots of flux. The parts where Silver Soldered with the flange flat on a fire brick (i.e. upside down) with a ring of SilverFlo-55 in place inside the barrel. This was heated and extra dabs of solder were added to make sure both sides of the copper shim were coated. The results are pretty good I reckon.
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