Someone very kindly looked at the boiler design for my Burrell and suggested some boiler end plate stiffeners. The conversation was based on a discussion on HMEM where I have posted images of the various stages of the design. Lots of people have very kindly offered help. Drawings, calculations and ideas. The model making and model engineering community is a very healthy place.
The original boiler design had 7 flue pipes in the lower half of the end plates.
The upper area being flat and unsupported. Hence suggestion of stays front to back or a stiffening rib.
As this boiler is tiny and I want to keep the volume as large as possible I thought a rib would be the best options.
The initial size for the stiffener was taken from a drawing sent to me. This rib is 2mm thick copper and ~35mm long and 7mm wide.
7mm is wider than required, but this means it ties into the endplate flange completely.
Kiln Silver Soldering Test
A simple test piece was used as this was my first time using high temperature silver solder in the kiln.
The Prometheus kiln had been pre-heated to 820°C.
The silver solder flowed rather well on this test piece. However, as you will see this was not the case with the real parts.
Silver Soldered End Plate Stiffeners
The Easy Flo 24 has not flowed as well as it should on these larger copper parts. I really should have used test pieces that were closer on mass and size to these. Silver soldering in the kiln takes time to learn and master.
One thing I should have down was to thin down the silver solder.
Although it still melts at the same temperature, the thinner section means that the heat will propagate faster throughout the solder.
I will remember that for next time. For now the boiler end plate stiffeners are good enough. Saving me from having to add stays.