Depron Delta version 3. Bigger, faster and night light LEDs PART 1Depron Delta version 3. Bigger, faster and night light LEDs PART 1
Sep 02 2012
This is a 2 part project, in part 2 I will go through fitting night light LEDs and the motor upgrade (when it arrives)
Big thanks to my sponsors: www.FrSky-RC.com and www.MyFlyDream.com
I decided to list this project under Design as the first 2 versions of this design cover the bulk of the build topics, so this time I will take you through modifications and design improvements.

Version 1 and 2 both had a 500MM wingspan * 320MM length. This version has a 600MM wingspan * 400MM length so a 20% size increase all over. The reason I went up in surface area was to increase stability and allow mounting of more components. Version 2 was fast but when loaded up with Micro-FPV equipment the flying characteristics went to hell with lots of wing-over rolling and tedious sensitive COG.

As well as increased size I designed all control surfaces to be operated from "in-line" servos so this time there is no control lines at all for the most sleek design so far. The motor set-up is not so perfect as I've come to find the Turnigy Air range of brushless motors are quite inefficient but fast, so while the delta did top 160KPH/100MPH the 1000mAh lipo only lasted 2 minutes!

I stepped down the motor to the version 2 Turnigy smaller one but do have a new motor on it's way for an update to this model OR I might move straight to version 4 as I have more design ideas on how to improve speed and reduce drag.

Also lastly I've had many requests on the design / plan for this and seeing as each project thus yet has shown how to build, that version 4 will not be as in-depth covered too allow the designers out there to see what I've done and those who are not designers to consider buying one in a shop right here on site sometime this year.
So same as in other versions but in the larger size I cut out 2 identical shapes in 6MM and 3MM depron foam.

Because of the more powerful motor I also added a strip of 2MM balsa wood. Also note unlike the first 2 versions the motor is recessed into the delta point for a more flush design. Carbon fibre rods run the entire length of span and length to spread stress load again.
Now the 3MM depron layer is sealed to the bottom increasing strength not only from the double depron but also from the carbon fibre acting as a skeleton frame.
Each project so far I've played with various layouts of in-line servos but this version I got it wrong. It is best to set the servos sticking out enough for the head of the servo to be reached with tools in case you need to adjust them. I made little cuts to do it but still best to do in advance to save this kind of trouble later.
This was the last servo to be designed as in-line with version 2 having a control line. I used the same technique here but adjust this servo head is near impossible unless you create a "poke hole" from below as you fit the tail so later you can adjust the servo.
Now all the control surfaces are fitted in place and you can instantly see how much cleaner the design is. No more control lines doesn't just mean less drag but less weight and better looking.
The balsa wood engine mount is the same as the other versions where it creates a sandwich effect between the depron and beginning of the carbon fibre rod. This transfers any stresses and shock across the entire span of the wing and not localised in 1 area, it's because of this you can really abuse this design with nose crashes, hitting objects and other things and it'll keep flying!

I've proved in many videos and now night flying (see below) how much you can do and get away with while keeping a fun fast agile delta.
This was the first motor the Turnigy Air series but it's gone and replaced for the previous turnigy 1650kv. So it's not as fast again until the new motor arrive with a near 3000Kv rating and a range of props (4.5*4.5 <> 6*4)
On the scales with it's slightly heavier design but this comes from the heavier motor and the lipo pack being 100 grams in itself.

Remove the lipo and this silly motor in place for the standard and it'll drop to near 170 grams. The model itself with no motor or lipo just receiver and servos is less than 140 grams!
Night flying this Delta is super fun, it's visible no matter where it is in the sky with orientation easy to follow. This is the most lights I've ever added too a model but super worth it!
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