Diamond Demon (oz8646)
About this Plan
Diamond Demon. Free flight gas model.
Quote: "Take a look at the Diamond Demon, modern from fin to cowl. Unique triangular fuselage construction that features real 'beef' without excess weight, and amazing simplicity of construction. High lift wing section, shock-proof landing gear, hefty motor mount are more of the Demon's features. Be the first in your vicinity to own this swell performer. Complete kit, full size plans, all dopes, wood, cement, and airwheels ... $2.95"
Note this plan is (I think) a later copy of the original, that was sold by Consolidated at 2/3 size of 32in span. It has now been rescaled to full size at 49in wingspan.
Direct submission to Outerzone.
Update 24/02/2020: Added kit review (of the Ben Buckle kit) from Silent Flight, December 1995, thanks to RFJ.
Quote: "Review: Diamond Demon. Nostalgia's not like it used to be. We bring Ben Buckle's classic up-to-date with electric RC.
The late Ben Buckle laboured long and hard researching past delights and the vintage movement does have a very healthy following world wide. Son Colin is keeping up the good work and has made some concessions to the current generation in offering details of radio assistance to a number of models in the range.
Silent Flight has taken this a step further and electrified the Diamond Demon, an original [Jerry Stoloff] design from 1937.
Typical of the era, this model features built up construction using the well established by then, method of balsa and doped tissue construction which gave a light yet rigid structure considered essential at that time. A generous undercamber gave a high lift coefficient and a slow flying aeroplane which was not so important then, as everything went away down wind at the same speed. Style was becoming a consideration and whilst today's eye would consider it a caricature of a light aircraft, that deep fuselage had its counterparts in full size aviation at that time.
So what do you get? As usual with Ben Buckle kits, well selected balsa and ply, good quality die cutting and clearly and easily understood plan and instructions. I needed to buy a pair of 2-1/2 in wheels but that was about all.
Build a fuselage: The drawings show that the construction is based upon a centre crutch of 1/2 x 3/16 in balsa and that supplied for the job was well selected being on the hard side of medium, true and straight grained. The drawings show hard wood sections let into the front of these longerons which are pinned down and glued up over the plan with spacers between. I didn't bother with the hard wood. The triangular formers are built up over the plan and glued to the crutch with a spine running the length of the fuselage. This is shown as one length of 1/4 in square, I used two of 1/4 x 1/8 in for a little extra strength. Die cut formers are provided and the underside of the fuselage rapidly took shape. The cabin construction and rear upper fuselage are equally quick. A hole through the front ply bulkhead will be needed to run the motor wires through and the undercarriage wire can then be bent and fixed in place before the front side cheeks.
The motor mount was made from 1/4 in ply and was made a little narrower that the fuselage to give a bit of taper up front. This was glued in to give around five or six degrees of down thrust, a guess admittedly but it seemed a good idea. A 1/16 ply deck cut out to accept the motor was glued in to reinforce the front end as can be seen in the photographs. A balsa former was glued to the front of this to enable the font to be sanded and a cooling duct also cut and sanded..."
Note the Diamond Demon was actually designed by Jerry Stoloff, not Leon Shulman. See the AMA biog of Jerry Stoloff at https://www.modelaircraft.org/sites... for confirmation. They in turn quote a 1937 Air Trails article as follows: "Jerry Stoloff designed the Diamond Demon, powered by an Ohlsson 23, and the meet was the first in which the plane had been entered. It has a span of 48 inches and weighs 22 ounces complete, ready to fly. Primarily designed for a contest ship, the Demon is unlike most ships of its type, having received much comment because of the simplicity of construction.”
Curiously, both the Ben Buckle plan and the Silent Flight Review quoted here credit the design incorrectly to Leon Shulman.
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User commentsTo complement your plan, I'm sending pictures of my Diamond Demon 1938 model [more pics 004-012]. I built the model as planned on Outerzone. I installed the Super Atom diesel /1949/ replica engine.
KarelSlupsky - 23/03/2018
Please find attached photos of my brand new Diamond Demon built from OZ plan, converted to electric power and of course radio controlled [more pics 013, 014]. Control surfaces added yet still retaining that wonderful vintage appearance.
AlanD - 03/08/2018
Added photo of finished model, thanks to GaryW [more pics 015].
Mary - 05/06/2020
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