DW Rainbow 800mm

Introduction:

I was actually in the middle of building another plane before taking this up. The reason I started this was because I got tired of repairing the FT mini arrow and wanted to see what a EPP wing of a similar size could do. Also, I figured this one would be lighter and with similar electronics, could be a lot faster.

Components ($45):

• Dancing Wings 800mm Rainbow
• 2x Tower Pro MG90s servos
• Emax MT2204 II 2400kv motor
• Micro receiver
• Emax 12a simonk esc Sunrise Model 20a ESC & 3A bec
• 5050 propeller
• 3d Printed Bonsai motor mount

Conclusion:

This wing flew great on the first flight. It needed much less reflex than I originally thought. The total weight was 167grams without the battery (260 grams with a 2s 1700mah battery). It doesn't fly fast with the 5050 propeller, but can definitely fly slow. I think that it will fly much better with a 6050 prop, but that will require me to cut away the foam a bit (which I may do later after flying it some more). With the 800mm wing span, it feels much more stable than the smaller DW mini rainbow - which is no surprise since bigger planes (in general) are easier to fly than smaller ones. After flying this, I am now very interested in putting a bigger motor of the Mini Rainbow to see what it can do.

The motor mount worked well and the best part about it is that it doesn't need to be glued in (removable). However, two of the legs snapped off the mount after the 2nd landing (not a hard landing). I am going to try this mount again except I will reinforce each leg by drilling a hole through each one and slipping in a push rod. I went with this mount over others in order to save weight, so I am hoping I can make it work somehow. Wing flex hasn't been an issue so far at this point, but that is probably because the wing is not capable of flying too fast with the 5050 propeller.

Update 1 (5/28/2017) - I was curious as to how it would fly with a larger 3s battery and decided to put one in. From the bench testing I did, using a 3s lipo did increase the thrust by a lot, but it also pushed the amperage by more than the 12amp max for my esc. I was too lazy to change the ESC, so I decided to try to fly it with a 3s 2200mah lipo at 2/3 power (which is already a lot more thrust than a 2s at max power). Long story short, the performance gains were not as great as anticipated mainly because most of the gains were used to push the much heavier battery. In fact, overall handling decreased by a lot due to the much heavier weight of the battery. For 3s to work properly, I would need to upgrade to a 20amp esc and find a 3s battery with no more than 1000mah.

Update (1/9/18) - I upgraded the wing with a 20a esc & separate 3A bec as there were blackout issues due to insufficient power from the smaller esc & built in bec. The blackout issues are all gone now and elevator throws are improved. The only issue is still the smallish props limiting more power to this wing.