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Old Apr 20, 2012, 09:42 AM
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United States, NY, Bethpage
Joined Nov 2011
101 Posts
Just off the bench- Free Flight Fokker EIII

Gotta tell ya, I really like the DPC/Aero-Werkes replacement wood packs for some of the older free flight kits.

Years back, I built the Sterling Fokker EIII using the stock kit wood and it was an easy build but heavy! It was a stable flier but not for very long. So when DPC/Aeroworkes started making replacement wood for this kit, I thought it would give me an opportunity to have another go at the kit and see if I could lighten it any further while it giving the scale treatment.

The wood was of good grade and the laser cutting, perfect. Trying to lighten it a bit more, I cut holes in the wing ribs using different sizes of tubing with the inside edge sharpened. Anyone who knows these old kits can tell you about how ungodly wide the trailing edges are. I cut the width in half but probably should have gone narrower. I made laminated wingtips to rid the wing of those needlessly heavy “planks” hanging on the ends. I like to add rigging when possible so I added small lengths of styrene tubing so that the “Stretch Magic” elastic thread I use will pass neatly through the wing.

This is a peculiar kit as you have to build and cover the wing and install it before finishing up the fuselage. Because my first one was so tail heavy, I wanted to remove as much rear weight as possible. I didn’t want to build (call me lazy) a totally new fuselage so I figured I try something different. I built the fuselage using the replacement formers and keels but widened the corner longeron notches to accept 3/32 sticks. After installing the formers and oversized longerons, I added the cross pieces and then cut away the formers and keels aft of the wing taking much weight off the rear end of this bird. I also moved the rubber peg one bay forward. I did leave most of the forward wood intact except removing wood from the inner edge of the formers making more room for the rubber. I’m sure the original intent of this design was for control line and not FF as there is little room for the rubber to pass under the wing due to it being mid-wing and one piece from tip to tip.

Being a scale nut at heart I knew I had to install a more correct landing gear. I knew this would add some weight but knowing it would be mostly forward. I like a nice strong gear so I went ahead with my plans building that crazy trapeze gear out of wire and added some wire wheels I made. The stock Sterling kit used a vacuformed cowl and cheeks but DPC supplied balsa and plans to reproduce them in balsa and card. Nice! Checking balance as I went along, I went ahead and used plastic engine cylinders from A2Z and made up my own engine gladly trading some balancing clay for detailing.

I like the adjustability of the Gizmo-Geezer thrust buttons. The hole comes drilled for a odd sized .055 shaft, but is easily drilled larger and bushed with brass tubing so that a more common 3/64 prop shaft will work. I went with a balanced and painted 7 inch Pecks prop as a start but might try an 8 inch later on.

After I finished covering and airbrushing on the markings, I balanced it in preparation of some test glides. Testing without the prop and rubber, I only needed to shim up the rear of the stabilized 1/64 of an inch to almost double the glide…surprising me when it hit the side of the garage. Don’t think it will be enough but I made up a 12” two loop motor of 1/8 rubber as a starting point.

When all is said and done, meaning prop, rubber and balancing clay installed, she’s still no lightweight at 55 grams (all that wire in the gear!) but still 15 grams lighter than my first and much more pleasing to the eye. Time will tell, but I think it will be a better flyer too.

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Last edited by SteveSw; Oct 26, 2012 at 08:45 PM. Reason: Added flight photos
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