SpeedFreak III custom design - built for speed and crazy fast with more to come
Apr 29 2013 by FaTe
Big thanks to www.FrSky-RC.com for providing the Receiver unit for this project :)
The SpeedFreak design series has quickly become a favourite of mine with it's fast speed and agile manoeuvring capabilities. The 2nd version had a meeting with the ground at high speed after I took off in the wrong channel lol. Anyway I still wasn't totally happy with the 2nd version with exposed control lines down the entire fuselage and other things like the aileron control lines going across the wing.
This is the fuselage size / shape for the SpeedFreak III. I'm still undecided if I want to make this for release after I work out more kinks, so for now I'll give you the photo step by step of the build for those builders good enough to see whats happening and replicate it themselves. Later if I decide not to release it myself I will do the final version with exact details on how to build.

The model has a 70CM span and is 60CM long. Fuselage is 4CM square to fit lots of different motor types.
The entire fuselage is built from 1.5MM plywood. Here at the front of the fuselage the inside is re-enforced with glass fibre cloth epoxied in place, I wanted maximum strength so I can really play with strong motors.
To keep this sleek I wanted to run the motor wires through the firewall front.
The back of the fuselage is designed to transfer shock and stress up the side walls into the center. When the wing is in place being solid balsa it's very strong.
Because the SpeedFreak is a low wing design I wanted the wing as low as it could be. To do this I recessed the wing into the fuselage making the bottom of the wing level with the fuselage itself all flush.
The wing slots into the fuselage on the front and then sits very tight in place, 1 nylon bolt then holds it down.
The balsa we get is always 1 meter by 10CM wide at different thickness variety's. So to make up a 70CM by 14CM root cord wing I had to join several pieces together.
This is not the final sanding just getting down to the profile I wanted.
This kind of design works best with dihedral to help the plane build up speed without having to use control surfaces so much.
Note how the middle of the wing is still a block shape, this allows me to build different wings to try out as long as they have the same 14CM center size as a block.
First pass over the model with Oracover. This was done using a normal clothes iron, I keep meaning to get a proper one. However I do have a digital heat gun which goes from 50c onward in 10c increments. I found at 130c from about 30CM/1ft away the film begins to stretch pulling out any deformities. Just don't do it too long you'll burn the Oracover faster than you release what is happening lol.
Now finished with all control surface connected and rigged.
A little tag label for it's name and model. Up front I used a plastic bottle top to make the engine cowling cover, I made a mould and heated the plastic slowly until it pulled in. It's not super but it does fit the shape and is more aerodynamic than a flat firewall.
Front view
Right side view
Left side view
Bottom view
/imgs/SpeedFreak/v3/snapshot 001/imgs/SpeedFreak/v3/snapshot 002/imgs/SpeedFreak/v3/snapshot 003/imgs/SpeedFreak/v3/snapshot 004
Some snap shots from the flight