Baudis recommend that the CG of the Skywalker is between 120-122mm. My Skywalker took just about 450g of weight to bring the CG to 120mm. I might push this back a little after the first few flights.
I made this slug from melting lead in a mess tin over a camping stove, it took a surprisingly short amount of time to turn to liquid. I then poured it into a mould made of tin foil, moulded to the inside of the nose. The mould sat in sand to keep it upright while the lead set. The whole process took less that 15 mins to complete and now fits perfectly inside the nose of the model. The correct amount of lead was measured by sticking it to the outside of the fuz first.
In the image below you can see the layers of lead that went into the slug. 20p piece for scale reference.
I added a little extra lead to the slug to bring the CG to 120mm. Here is it installed into the nose.
Since I had an S-BUS2 port free I added a Futaba SBS-02A altitude sensor and vario so I can find lift and check my altitude. I tested it at home and it’ll be great for those lazy summer days hunting for thermals 🙂
The nose of the Skywalker is 2.4GHz safe, so before the range check I built a simple tool to keep the antenna at 90° from each other.
Close up of the 90° tool
*Edit* After reading a fantastic article on 2.4 GHz antenna placement I quickly scrapped this idea to spread out the antenna a little more. The article is called Introduction to Antennas and it’s definitely worth a read for those of you who use 2.4 radios. I’ve been a little concerned with the carbon insulating the antenna so I’ve been more cautious than a regular epoxy/glass model.
After this article this is how I finally installed the receiver antenna.
The surfaces were all set up as per Baudis’ guidelines as follows:
Outer aileron – up 15 mm / down 8 mm
Inner aileron – up 10 mm / down 6 mm
Flaps – at max roughly 75°
Elevator – +-10 mm
Rudder – +-25mm
I’ll make a video of the mixes in a later post but I’ve got flap/aileron, aileron/rudder, and butterfly mixes set up.
I used a Höllein control surface deflection meter to get nice accurate measurements of surface deflections. Here it is in action.
Finally I bought a fuselage bag from Revoc which I thought was essential to keep the fuz in tip-top condition!