The folding arms are also designed that way to help make it portable, but also so that it folds in a crash instead of breaking. As long as they are tight and not flopping around you should be fine.

Also sai, did you say you used locktite on the locknuts as well? No need to use it on a nylock, the cutting of the threads into the nylon is the lock device.

-Scott

Yes...the folding arms on impact are one of the things that really appealed to me about Dave's build, since I knew I would be crashing :-). After years of spending hours rebuilding my Trex after a crash, I decided I wanted something that was quick to patch up and get back into the air quickly after any unfortunate event.

I only locktited the screws and nuts holding the frame together, not the nylon ones on the props. Locktite + plastics = mush, so I always steer clear of that.

Crash! Good to hear from you. That is great about your (impending?) official Storm-Spotting credential. Are any of the other ham guys involved in that? Sounds interesting. I'd like to hear about it when we see you next.

I'll make sure I keep you updated on possible fly days. It would be great to have you join us. Doc and I had fun this morning doing some maintenance and tuning on his 450. It was flying really well once we got through with it.

What's the matter? One set of rotary blades wasn't enough for you No but seriously, very nice work!

Sai, being a Texan I figured you knew better then to locktite a nylock, but good to put out there anyhow for anyone else reading the build thread ;-)

The build is awesome, and I am sure I will be bugging you some in a month or so on flashing a KK board for dummies.

-Scott

Originally Posted by Scott_NJ

Sai, being a Texan I figured you knew better then to locktite a nylock, but good to put out there anyhow for anyone else reading the build thread ;-)

The build is awesome, and I am sure I will be bugging you some in a month or so on flashing a KK board for dummies.

-Scott

http://rcexplorer.se/Educational/HKKK/HKKK.html

seems pretty straight forward. Did you follow that guide sia? Was it pretty straight forward?

So...Let's say it could have been that simple. Dave's flashing guide is one of the best, and I used it a lot. I did have to find key bits of info in other places, though, so for me it was not one-stop shop. If all of the elements had been the same as Dave's, I'm pretty sure it would have been a breeze. As it happened, it wasn't anything major, just that I ran into a couple of issues that I had to wrestle with a little. If I remember correctly, I spent about 2-3 hours on the flashing process, including reading Dave's flashing guide, downloading and installing the software, running into a couple of problems, reading up on the forums, trying a few things on my own, and ending up with a working tri firmware on the board. I'd say in the big scheme of things, that operation went well, and I learned some useful things. Reasons for my different experience:

1) The board was different (his was HK V1, mine was V2.1)
2) The programmer was different (his was usbasp based, mine was tinyusb based)
3) He was using a mac, and I was using Win7

I don't know if the board version really had to do with any problems, but it was a difference so I wanted to point it out. My PocketAVR was part of the problem. First, I'd hoped that I could get it to work on my mac (and be like Dave :-), even though on the Sparkfun product page it said that there had been a lot of problems reported with mac and linux. But I decided to take the chance, since I use both mac and Windows at home, and because I like Sparkfun as a vendor, and it was domestic shipping and a company with real people and customer service, etc.

As it turns out,while someone may be able to get it working with a mac at some point, I was not, so I had to move to the Windows7 box. By the way, the problem on the mac has to do with the driver, I believe.

Turns out there is a sort of driver-related problem on Win7 with this programmer, too. Although I saw some posts that indicated that the driver was indeed a valid signed driver, Windows 7 did not agree with them. To use the current PocketAVR driver on Win7 (64bit), you must reboot and press F8 during post to bring up the Windows boot menu, and choose the disable the driver signing requirement in order for the driver to be "trusted" and installed. That setting stays in effect for the duration of that boot session only. It is cleared on the next reboot (unless you set it again.) Note that this problem is specific to the PocketAVR (and any other similar devices whose drivers are not recognized as validly signed).

The second issue was with the flashing process. Once I had Windows and the flashing software seeing my programmer, the flashing process initialized properly, and went through the first read/write steps successfully. But once it got to the final actual firmware write operation, it hung on the "writing" step, and progress indicator just sat there. I found a couple of posts referring to this issue that suggested moving to previous versions of the flashing software. I don't recall what the recommended version was for resolving this problem, but I had to revert to an even earlier version before it worked for me: version .33. Note that .33 pre-dated the availability of the HK KK 2.1 version of the board, so I selected the closest thing, which was version 2.0.

That combination worked for me. If you do some reading (especially the KK thread: http://www.rcgroups.com/forums/showthread.php?t=1458663), you'll find evidence of all sorts of little sticking points that different people with different versions of this or that had to work through. Some of them much more troubling and persistent than mine. Based on my experience, I would say to expect some fiddling around with the flashing process before you nail it, and consider yourself fortunate if everything just works the first time around. As I mentioned, I like that I had to jump through a few hoops because I learned some useful things in the process.

On a sidenote, LazyZero (the author of the kkmulticopter flashing software) said that he would order the PocketAVR to do some testing, and so that issue may be something he is able to address in a future build: http://www.rcgroups.com/forums/showp...postcount=1376.

Hopefully this information will save someone a little frustration at some point.

-Sia

Originally Posted by jarod120

What's the matter? One set of rotary blades wasn't enough for you No but seriously, very nice work!

must....build...more....flying....things....with.. ...cameras.....arrrgghhh

lol. You're one to be talking, Jarod. What are you up to now? 5 flythings? 10? :-)
This is only my number 2 (unless you count my Walkera 4G6S for sale over on the classifieds...http://www.rcgroups.com/forums/showt...highlight=4g6s...shameless plug!)

I thought flashing the firmware on the hk quadcopter v2 board was going to be hard but damn it only took me 10 secs.

Here is my frame I am using the HK CF plate .. hope it stand up in a hard crash.

Aw yeah! That is going to look killer, freshmint. Tight! After seeing yours, and having to deal with the occasional wire getting caught as I fold and unfold, I think that if/when I have to replace my frame, I'll switch to the "coffin" style like yours.

That is great that the flashing was a breeze for you. Would you mind posting your specs here for others to see? Like board version, programmer version, flash software version, firmware version you decided to use, and whether you used a mac, or Windows 7/XP, etc...

This is the tree I decided to smash my tri into for it's first crash. Well, no it wasn't on purpose, but I knew it would happen at some point. I'm still getting used to the difference in response between my Trex and this Tri. There is a lot more airframe for the motors to sling around with the Tri, plus the whole approach is supposed to favor stability and smoothness of flight over acrobatic responsiveness. Soooo...I didn't react quickly enough as I came towards the tree and smacked into to it head on...one arm leading the way.

Results? Front right motor zipties snapped. The motor was still hanging by its barrel connectors:



The arms stayed mostly extended, although the right arm started folding about 2 mm or so:



The prop was also compromised (see stress mark near hub):



And how did the RCE Tri do in terms of recovery?

• Reconnected the motor with 2 new zipties...3 minutes, 0$
• Drilled out, balanced and installed a new prop...7 minutes, $0.25

I was in the air finishing my pack in about 15 minutes. If I'd crashed my Trex into that tree, I would have been replacing one or both blades, probably the flybar, probably the main shaft, to a tune of about $25, and at least an hour of build and test time.

Let's just say that I am very pleased with my first crash. Lol, I know that sounds kind of wierd.

Originally Posted by freshmint

what are you using for the landing legs? plastic strips?

Large Zip ties.

Originally Posted by sia100

At this point, the only thing I know of that needs work is the landing gear. I really like what crezzee did with his. Big black zipties:



Lol...here is what mine look like right now...all squished down. Not sure if my rig is that much heavier, or the zipties are too thin, or too short. Crezzee...any comments?

Sia, I used Truly massive Zip/cable ties, industrial ones that are the same width as the arm (about 10mm). The ones you have used don't look that phat, go get a handful of monster ties.
I have flown my tricopter quite a bit now and the cable ties are still perfect.
My mate tried to loop his tri and it kissed the weeds big time, it went in flat out inverted and the only thing it broke was a few cable ties, a prop and a broken kk board. Total crash cost about $18 including postage to the UK.

Thanks for that info about the mondo zipties, crezzee. I didn't know they came that big. You think I could find them at an auto parts store?

I strapped the gopro to the tray and made sure it would hover. Then I took it outside for a quick look-see. Works great!

Note: The scratchy sound ended up being my velcro battery strap rubbing on the case mount (or on itself). That said, I think there are still vibes that need to be ironed out. The recording quick test flights with the gopro might end up being a good way to monitor the effect of different vibe elimination changes.

First RCE Tri Hover with GoPro 2 (1 min 10 sec)

I love the quality of the video! It kind of sounds like a monster that's coming to get you

How small do they make these Tri-copters? This would be a great design to scale down. I bet you could get one of these flying around your house near whisper quiet.

Originally Posted by sia100

Thanks for that info about the mondo zipties, crezzee. I didn't know they came that big. You think I could find them at an auto parts store?

Yeah Auto parts store should do it or maybe an electrical store.