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Posted by thwaitm | Jan 11, 2013 @ 08:37 AM | 4,638 Views
As others have said, you need to make sure that your swash is in the middle of the gap between retaining collar and the base of the rotor head.

To do this you need to first remove the blades or back the motor away from the main gear to avoid injury. Then set your TX to send 50% pitch - I use throttle hold, set L to -100, 1 to 0, 2,M,3 to INHIBIT, 4 to 0 and finally H to 100. This way, you know that as long as your collective is roughly centred you have 50% pitch.

Bind the TX with the heli and make sure you are getting some servo movement. Set the collective stick to somewhere in the middle.

Then remove the screws and move your servo horns/arms so they are all as close to level as you can get them - ideally they should be completely horizontal.

With the horns level, adjust the links between servos and swash so that the swash is centred, level and moves from bottom to middle to top remaining level. If it doesn't, go back and recheck, re-adjust (be sure that the ball links are all in the same holes etc). If you hear the servos straining at either end, use the Travel adjust menu to reduce the PITCH travel (mine is at ~+/-55% with my slightly non-stock setup).

Once your swash is levelled and centred at halfway then you can go ahead and attach the swash to blade grip links - adjust these so that the bolts to hold the blades are vertical. Once you're good, go back and attach the main blades.

Check with a pitch gauge or at worst with both blades swept back together...Continue Reading
Posted by thwaitm | Dec 01, 2012 @ 10:12 AM | 4,641 Views

With exception to the ping pong balls, everything else can be purchased at Jo-Ann Fabric and Craft Store. You will find many diameters and lengths in the bamboo knitting needle rack (thanks to my wife) and I can't remember which ones I bought but just remember they have to be long enough and not to big in diameter that would add needless weight.
The light weight square wood dowls you will find at Jo-Ann's also. They are made by LOEW CORNELL p/n 1021231 and come in a bag of assorted sizes. Again use the sizes that would be small enough to do the job.
Ping Pong Balls I bought at Dick's sporting Goods but you can pick them up about anywhere.

1. Get a couple sqare wood dowels out of the bag that would be large enough for you to drill holes through for the bamboo legs you have selected.
2. I kept the 12" length if I remember correctly or cut them to the rotor diameter if they were longer.
3. Find exact center on the two sqare dowels and notch them out so the will fit flush to each other in a perfect "X". Once your satisfied with the fit glue them togeather.
4. Drill the holes for the bamboo legs.
This must be done carefully so each leg will be in line with the square cross member it's inserted in and at the proper angle.
The angle of the leg will be set by drilling through the square cross member by useing a Kobalt Utility Blade as your guide to set the angle.
Please do not cut...Continue Reading
Posted by thwaitm | Jul 21, 2012 @ 04:24 AM | 5,501 Views
Lots of people ask about how best to make a flashing connector for ESCs. It depends a bit on what you have around and what you're trying to flash but this is the tool I made which requires no soldering and works very nicely for ESCs with inline pads like the HobbyKing F20A/F30A series. It can be adapted with a bit of patience for the smaller 10A ESCs as well.

I used:
6 female to female connectors (available on ebay)
a standard header - 6 pins worth
and a USBAsp programmer

Take a look at the photos.

Press hard enough with the header to the pads to make sure you get a decent contact and maintain that pressure during the flashing process. If you get a verification error - flash it again.
Posted by thwaitm | Jun 18, 2012 @ 02:19 AM | 6,797 Views
The pic below shows what's required to calibrate multiple ESCs in parallel for Quad/Hexa/Octo copters.

It assumes the power harness is connected to all ESCs
Posted by thwaitm | Jun 04, 2012 @ 12:02 PM | 15,051 Views
For anyone who might be interested, I've hacked the Devo-10 A 100mW firmware to work on the B 10mW version.

The process was based on work done by FDR_ and rcH4x0r who did the same thing for me and my Devo-8 10mW Tx.

Needless to say, this is unsupported and might trash your TX.
Not for the fainthearted!

You need,
  1. HxD - Hex Editor - free
  2. DFU Tools from FDR_

The method:
In the Devo-8 hacked firmware there is a string of 10 repeating bytes 00 C7 in block 184D-1856.
In the original FW for both A and B versions this same string appears at offset 1853 in A firmware and 184B in B firmware.
It's just before the 4 bytes 44 45 56 4F which spells DEVO.

In the Devo 10, the same 4 bytes 44 45 56 4F occurs at offset 1111.
Again, just before this there is a similar series of bytes except this time it contains 00 C9 at offset 110B.
Replacing the 10 bytes in block 1105-110E with 00 C9, saving the hacked firmware and recalculating the CRC enables the 20db option in the Devo-10.

See the attached PDF for screenshots helping you through the process.
Posted by thwaitm | Feb 06, 2012 @ 09:59 PM | 6,125 Views
Attached is data from CrystalDiskMark on the microSDHC cards I own.
Posted by thwaitm | Jan 16, 2012 @ 09:05 AM | 6,204 Views
I was joking about V120D02 FPV flight when CANNONFODDER said it had already been done. I researched a few suggested links, decided to bite the bullet; stripped my key fob camera's case can started thinking how to mount it to the heli.

Pics and construction notes to follow shortly below...

Gave up on the old camera since after reading Chuck Lohr's site I realised I had possibly the worst version of the 808 style camera. 1 real frame in 7 version... useless for on board flight video.

------ New camera #16 808 arrives ------

12 Feb 2012
So after a few different attempts at securing the camera to the skids I decided that this might be a viable option. I just received my #16 808 camera and have glued two pieces of silicone fuel tube to the fob. Split with an xacto and it clips securely to the carbon training gear rods which I've attached as skid braces. Clips in the same position every time (not adjustable but removable).
I think I have a bent feathering shaft and need to replace it to smooth out the vibes but I'm already quite satisfied that I'm on the right track to a simple and solid mount.

13 Feb 2012
Changed the feathering shaft out for a new spare... worlds of difference. Clear video - way better than anything I've been able to manage on anything other than my 450. Now just need some good weather to get to test it outside.

V120D02 + #16 808 (0 min 55 sec)

After testing outside I found that the camera vibrates on the mount and thanks to E10 who suggested just adding a rubber band to stabilise it a little further.
Also key for this platform is that the heli tail is tuned properly for the head speed and associated torque. I've found that if I change my throttle curve I have to readjust my tail. Since the indoor and outdoor setups are quite different for this heli I can get lovely smooth video indoors but it jellos like mad outside unless I tune the tail in rate mode and then return to HH.
Posted by thwaitm | Dec 17, 2011 @ 09:58 PM | 6,323 Views
Recently I've been flying my V200D01 quite a bit and I added a light kit. I sometimes fly with a key fob camera attached and recently I noticed that the video quality was really much worse than some of the earlier film. I decided to find out why.

On visual inspection there wasn't anything obvious but holding the heli vertical (nose up up, tail to the floor) I noticed that my tail rotor could at some point rotate freely. Turns out the B/C cone gears were a little worn. After replacing them things were much better. My tail is now fully controlled by the main rotor just as it was when it was new.

Since I was in the mood for fettling ( I decided to check if I could improve the vibration I'd noticed. I was guessing it was the blades. I took them off and put them on my balancer, both ways round and it was pretty level but I was sure there was a problem - holding the heli in my hand no blades, no vibration, in my hands with blades and I had a definite wobble. Time to take a guess... I added a small amount of tape to one at the balance point and found it improved slightly, I added a bit more, 4 times until I decided that 2 or 3 pieces of tape were best. It's still not 100% perfect but with the tools I have the best I can do for now.

Next, tracking... A black marker pen down the leading edge of one blade, a head lamp and a couple of spool ups and a twist of a link or two later the blade tracking was spot on.

Then -...Continue Reading