Building the deHavilland Cirrus Mk I


Created: Feb 2005
Last update: September 2006


The late Merritt Zimmerman designed replicas of the DeHavilland Cirrus I in 1/4 and 1/6th scale. He built several for sale (I've heard the figure 25 bandied about), and presented the plans to Robert Washburn to help kick-start SIC Magazine. The 1/4 scale version was built and documented by Ron Colonna. Eric Whittle did likewise with the 1/6 scale version and later reduced it to 1/9 scale. His plans and the construction feature for the latter appeared in English magazine, Engineering in Miniture. The cylinders, pistons, 'rods, and head of this engine formed the basis for Eric's Aero V8 that was serialized in the Model Engineer. This makes for a very satisfying symmetry, as the full-size Cirrus I, designed by Major FB Halford, began as the (metric) cylinders, pistons, 'rods, and heads of a WW I era Renault V8!


Despite my intent not to write about the construction photos, I've weakened under urging from others and added some words of explaination on the less obvious steps, plus a couple of gotcha's.

   Pistons and Rings
   Valve Gear
   Cylinder Head and Manifolds
   Engine Mount and Running

By the way, the Cirrus Mk I picture at the top of the page is Kurt Bjorn's. Click on the pic to read about it.





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