Trevithick Dredger Engine- First silver soldering session

by John

Today I fitted the chimney right angle piece, drilled and soldered on its flange, and drilled the end plate to accept the flange.  Then I CNC drilled the big bronze end plate to accept the flange.

 

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The angle piece is a commercially available plumbing part.  The stainless steel square nuts came from China.  Joins are silver soldered.  In a departure from the Tubal Cain/Julius deWaal plans, I decided to attach the chimney flange directly to the flat end plate.  I reckon that’s what would have been done in 1806, and it is what shows in the 1820 Rees Encyclopaedia drawing.   Note the unwanted threaded holes, now filled with stainless steel threaded rod.

Then I carefully positioned the bronze end plate, the firebox and the firetube, and silver soldered them together.

 

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The parts are fluxed and pushed together, ready to apply some serious heat and expensive silver.

 

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Not pretty, but I am happy with the silver joins.  Minimal retouching required.

Next, the inspection hatch will be soldered to fill the rectangular hole.

Then the main bronze flange will be permanently attached to the boiler shell.  I intend to silver solder it, but considering bronze brazing.