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Posted by luovahulluus | Apr 19, 2013 @ 09:41 AM | 3,779 Views
Superlight foam canopy

Some time ago I was looking for a way to make a lighter canopy for my V911. After looking through some paper canopies, I found a funny looking Angry Birds canopy for Solo Pro by AngryBirdie, made out of packing foam. What really caught my eye was the weight, only 0,5g! So, a few nights ago my g/f was having fun with her friends in a bar and I'm home all alone. I decided to have some fun of my own and pulled out some thick paper, a foam sheet, gluegun and scissors, and started cutting and pasting

This is version 4, which I think is not totally ugly (esp if you paint some windows or somethin on it). I included a .pdf file so you can make one too. If you are using non-A4 size paper, just be sure you don't shrink/enlarge it as you print. There is a true size or scale 100% option or something like that. Just get some packing foam, print and cut the template, and draw the template outlines on the foam. After cutting the foam, glue the long curved edges together. I tried CA first, but it just melted the foam. Also my hot glue gun melted it a little, but you just have to use as little glue as possible and be quick about it. I glued it about 1cm at the time.

I'm not sure how much my version weights (as my scale didn't even detect it), but compared to AngryBirdies canopy, I believe I used a little bit less foam, but mine was thicker. AngryBirdie used 3mm and I used 5mm foam. My guess is I'm around 0,7g with this, which is about 1,5g lighter than the stock. That's almost 70% reduction!

If you decide to make one, please post some pictures
Posted by luovahulluus | Apr 18, 2013 @ 10:19 AM | 4,718 Views
Improving FFF by making a resistor mod to V911 servo

Coolthoughts posted here a post that I found very interesting. His newer V911 (a clone) was more sluggish than his older rev. 05 V911. He traced the problem to lower servo voltages in the newer bird. The post seemed to go unnoticed, so after a while I pm'd him and asked if he had found a solution. And indeed he had.

Coolthoughts' solution was to add a resistor to the lead of the pot of the servo. A servo has a feedback potentiometer that tells the servo motor if it should turn more. This mod changes the range of the potentiometer so that the motor turns the servo horn further.

I made the mod for my rev 05 V911. Coolthoughts used a 1k ohm resistor and I used a 470 ohm one. The weather has not been my friend lately, but I just managed to find a little time between rain showers. The wind was still way too strong for relaxed flying, but I had enough FFF speed to fight it. Even the smaller resistor made a clear difference on the angle of attack, and the copter can now fly alot faster and has more authority when flying in the wind. I'm very happy with it, but I wouldn't do this mod to my rev 07 V911 as it can easily reach steep enough angle of attack. With a steeper angle more of the motors thrust is translated into forward motion instead of just lifting it up. Edit: With a 470 ohm resistor the range went from 71 degrees to 84 degrees, so it's 118% of the original. Coolthoughts reported that with 1k ohm resistor the range is...Continue Reading
Posted by luovahulluus | Mar 31, 2013 @ 06:32 AM | 5,521 Views
Disclaimer: I'm a noob with about 10 days of flying experience with anyting.

I did yesterday the resistor mod for my V911 stock tx. It's a HUGE difference! My bird is now a lot easier to fly, even indoors with the more aggressive "mode 2" rates. I very much recommend this mod to anyone flying with the stock tx!

At first I had 2.2k ohm resistors for the yaw control. IMO it didn't make enough difference, so I replaced them with 1.5k ohm ones. I ended up putting the 2.2k resistors to the left/right cyclic controls. After testing some more, I added 2.2k resistors to the forward/backward cyclics too. I also added a 100 ohm resistor for the speaker. It is still clearly audible, should have used even smaller resistor to make it even more quiet.

If you plan to do this:
I had no prior experience with smds and very little other soldering experience too. Also my soldering iron is a cheap 40W one with a bad tip. However I'm pretty good with my hands and used to working with tiny things. These are just some things to consider when trying to decide if you should try this with smds.

I used tiny smd resistors salvaged from an old hard disk and a cd-player. Those are about 1mm x 2mm. The markings on the resistors have a logic:

222 => 22 + two zeroes = 2200 ohm = 2.2k ohm
152 => 15 + two zeroes = 1500 ohm = 1.5k ohm
101 => 10 + one zero = 100 ohm

Something to see before trying this:
How and WHY to Solder Correctly
Smd soldering tips
Posted by luovahulluus | Mar 06, 2013 @ 12:39 PM | 3,443 Views
List of mods I have done or plan to do. If you plan to mod your V911 here is a good reference list for known mods

My goal is to make the copter very agile and fast without losing too much flight time. I started this list even before I got the copter, and plan to keep track of my mods here in the future too.

To be updated....