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zagi zagi thl stiletto siesta filip400 simply the best nano floh skorpion

selection

I already had the standard epp zagi.
Only problem with it being a bit heavy.
Enter the thl.
External dimensions exactly the same, but much lighter construction.
Something stress free to fly when the wind's not so strong.

construction

2 piece foam semi symmetric wing cores.
These are the same shape as the standard zagi, but only the front 1.5" is crash resistant black epp foam, the rest being made up with extremely light, fragile, white, ceiling tile type foam.
The wing cores are epoxied together while sitting in the foam blanks giving no dihedral.
The kit was supplied with no reinforced tape, even though the instructions recommend using a little for strength.
Instead, just some coloured (yellow) tape is supplied.
I considered yellow, but rejected it, as being hard to see against the dried grass on the slope.
I tried using some transparent parcel tape, but couldn't get enough stick, even with spray mount.
In the end, I used the same reinforced tape as on the standard zagi, which I had leftover from the kit.
This will have made it heavier than intended.
Plastic fins have been left uncovered and without any balsa trim, to save weight.
I used 2x hitec hs81mg servos and a hitec slimline dual conversion Rx.
I left the Rx antenna just blowing in the breeze, rather than add the weight of a tube down to the tip.
I omitted a power switch, again to save weight, just using a an extension to allow the Rx to be connected to the power pack.
I used my own reverse engineered emulation of the Ken Hewitt mixer.
As I could reprogram it, I could do away with the config switches.
I also wired the servos directly to the vero board to eliminate any extra connectors.
The only components required being the 16f84a pic itself, a 4M resonator and a decoupling capacitor.
This added a measured 8g.
More detail over here.

I covered it before fitting the elevons, so I couldn't use the specified reinforced tape as a hinge.
I used mylar hinges stapled into the foam/tape and pinned into the balsa elevons.
Again, I changed the orientation of the servos slightly so that the pushrods are perpendicular to the control surfaces rather than in line with the air flow.
I initially fitted the recommended 110mAh nicad pack, but this is a bit of a waste of time as it needs extra nose weight anyway.
I didn't want to use my standard red solarfilm, so that it would be quite distinct from the other zagi.
I considered yellow, but ended up being tempted by some luminous pink stuff, which is after all, a light red.

flight

Flown for the 1st time Long Mynd reservoir slope May 2002.
Miserable damp, misty weather, but with some lead taped on the nose, it flew reasonably well.
I need to replace the warped elevons.

statistics

more photos

2002

zagi thl in the mist on a miserable damp day.Long Mynd reservoir slope May 2002. Can you see the other?

zagi thl after the ground appeared out of the mist unexpectedly on a miserable damp day.Long Mynd reservoir slope May 2002