First Rotor Bones Build Questions

[slappySF]

OK gang, I have almost everything I need to build my first Rotor Bones 370 quad.

Still waiting on a couple parts. Primarily the flashing cable for the KK2 board. Should be here this week.

Meanwhile, a question:

How do I drill perfect 90 degree holes in my wooden booms if I don't have a drill press?

In Chad's build vid he uses the guide to mark the holes, then whisks the boom over to a drill press. But I don't have one of those.

So...short of buying a drill press which I really don't need for anything other than this...any suggestions?

Assuming that they need to be 90 degrees exactly. If they are not, will the motors mount out of alignment, or will I miss the holes on the bottom plate? Neither sound good.

So looking for that perfect 90 degree hole drilling solution.

I'm sure I will have other questions along the way.

Thanks in advance, gang.

- Henry Joe

 

[jhitesma]

Just go one size up on the drill and do the best you can. With a bit of practice you'll probably even be able to drill straight enough to not even bother with the slightly larger drill. Ultimate precision isn't really important on the FT designs.

 

[andybenton]

I clamp the wood to a table, hang the portion to be drilled over the end, then focus on getting the drill bit vertical with both hands.
With both hands free to hold the drill Ivan move around and get different perspectives, go slowly and spend some time squaring things up and you'll do fine.

Clamps are really helpful for a lot of things, and if you don't have one, I'd suggest you get a few they'll make life easier

 

[FinalGlideAus]

Find a friend and get them to look at it 90 deg from your position. That way you can concentrate on keeping it straight on the left/right direction and the friend can give you pointers on it's forward/backward direction.

If I can once again steal words from Cranial, Practice on a scrap piece and then when you're getting the hang of it..... "Drill baby drill!"

 

[cranialrectosis]

The better you drill, the better your copter will fly. That said, if you are new, you don't yet have the flying skills to know the difference unless your holes are DRASTICALLY off.

Use the 9/64th bit to give you some wiggle room. The holes don't have to be perfect just good enough.

I recommend measuring, punching a dent in the boom where you want the hole so the drill won't 'drift' and practice until you are confident. Boomstick is cheap. Buy it 32" at a time from Lowes or Home Despot (sp on purpose). You will want it to build spares anyway.

I also recommend you not push the drill. Let the weight of the drill carry the bit through the wood and put a piece of scrapwood under your boom so when the drill punches out the bottom you don't 'blow out' the hole.

It is also possible to build a jig by connecting two pieces of wood at right angles and putting your bit in the corner to keep your drill straight. Basically, you build a "T" with wood clamp it to your bench and your project and put your bit in the armpits of the "T" when you drill.

The beauty of the FT kits (and I have 3 of them) is you don't have to get them perfect. This is key as you will break booms when you crash. Get in the habit of building one or two extra booms and drill them all at once like an assembly line. This lets me get into a rhythm and the holes tend to be straighter as a result because I stop overthinking it.

Welcome to Flite Test!!!

 

[slappySF]

Great tips, gang! Thank you all so much!

 

[arsenalj]

I use a pin vice to start the hole and check if all lines up while drilling all the way through. It is always easier with a pin vice becuase it is so small and you can use one hand to drill while using the other to hold and check everyhting. After you do that then drill the hole to size. You won't drill at an angle because it will follow the starter hole. Hopefully I explained that right.

 

[slappySF]

Yes! Great idea. I have a pin vice.

I also have a Dremel, and I see you can get a Dremel workstation that will function as a drill press for $39, which is much more reasonable than buying a giant drill press for my overstuffed garage.

Considering...

But the pin vice strategy is a great call, too!

 

[jhitesma]

A few additional tips.

A center punch to mark where you're going to drill and brad point drill bits help a LOT. Getting the hole started in the right place and angle is important as it's much more difficult to correct a hole once it starts going the wrong way. A center punch lets you make a little divot to position the tip of the drill - and brad point bits have a little point on them that can center itself very easily in a center punched mark.

The brad point bits are also flatter on the end which for me makes it easier to keep them straight.

Finally Instead of hanging your workpiece out over an edge I'd strongly suggest putting it on top of a piece of scrap instead. This will keep the backside of your holes MUCH cleaner and prevent them from splintering and tearing when the bit exits.

Even cheap brad point drills make it so much easier to drill accurately, I picked up this set at HF a few years ago on a whim but have fallen in love with them:
http://www.harborfreight.com/29-piece-brad-point-wood-drill-bit-set-35837.html

 

[moldavia]

I have the Dremel work station, and it is iffy. Quite a bit of slop in it for doing anything precision, still works though. Harbor Freight has a small benchtop drill press for less than $80. If you have room for it.

 

[DDSFlyer]

I got the Drexel drill press and while it does have slop in it, it makes a mich straighter hole than I could with my two hands. Just turn up the speed and go quickly, works great! Cranked out 16 arms in no time!

 

[slappySF]

Progress!

- Got the frame built. Except for the battery plate. Gotta screw that on.
- Spray painted the booms obnoxious colors to help with orientation.
- Got the KK2 board flashed. I think (I hope!) it was a success.
- Will balance props tonight, mount motors, solder ESCs, and get those installed.
- Tomorrow I will wire the RX and the KK2 and start tuning.

Hope it continues to go well...

 

[slappySF]

Hey gang,

Build is going fine. More photos, soon.

Getting ready to do the KK2 setup and tuning.

Question is this -- does anyone care to share their ideal P-gain/P-Limit and I-gain/I-limit settings for their Rotor Bones 370 quad setup?

Going to use the settings listed on this video as a basis.

https://www.youtube.com/watch?v=0W7PiV6qvWc&feature=youtu.be

They are:

Roll/Pitch P Gain: 75
Roll/Pitch P Limit: 50
Roll/Pitch I Gain: 40
Roll/Pitch I Limit: 20

Yaw P Gain: 75
Yaw P Limit: 20
Yaw I Gain: 30
Yaw I Limit: 10

But the video shown and setting above are for a different quad, and probably behaves differently.

Wondering if any of you had settings you have and like for the RotorBones 370.

I'm new to multirotors, so docile, noob settings are not insulting to me!

Thanks in advance, gang!

- Henry Joe

 

[slappySF]

OK, here's a pic of her all wired up and ready to go.

I took her into the back yard (It's San Francisco, so my back yard is the size of a postage stamp, only smaller) to at least get her off the ground.

And the verdict is...she flies!

Very happy.

Hope to get her to the local park after work one of these days where there is a little more room to play around.

So glad I've been putting time on the stick with that little NanoQX. It's really coming in handy. Not ready to do figure 8s yet, but I do have some control.

She tends to drift toward me, so I'm watching those tuning vids to see how to compensate for that before I use the trim on my tx.

More reports, soon.

Menwhile, here she is all wired up.

 

[FinalGlideAus]

Congrats mate, it's a great feeling isn't it

With regard to drifting, first make sure that the drifting is happening in dead still air. That is to make sure it isn't wind that is doing it. To fix the drift make sure firstly that when you calibrated the board that it was on a dead flat surface. Next go into receiver test and make sure all channels except throttle and AUX have Zero's next to them. If they have anything else, use the sub-trim trim function in your radio to change the numbers to zero. This will fix the drifting in Acro mode. It won't hold level forever because it's acro mode but it shouldn't drift a certain direction all the time. To fix drift in Auto level there is a screen to adjust the P and I gains for auto level (can't remember the screen's name off hand). Under these things is ACC TRIM which you adjust to trim the craft Left/right and forwards/backwards level in Auto level mode. There is a video on how to trim in Auto Level mode in the Multirotor Top Tips sticky post.

Hope that helps.

 

[slappySF]

Final Glide,

Thanks so much. It does indeed feel like quite an accomplishment. I'm a plane guy, so whenever I saw guys with quads with a million wires and speed controllers and printed circuit boards, I always thought to myself I could NEVER do that. Well, here I am now. I did it!

I have the video on how to trim in Autolevel mode and will be doing that tonight.

I already did the receiver test and zeroed all the appropriate functions with sub trim. The backwards drift happened after that.

I think I will do it over again on a surface I'm 100% sure is level. Don't have that confidence in my garage floor...got a drain in the middle and it probably slopes slightly.

One thing I will address tonight also is how the KK2 board is mounted to make sure it's level. I did as Chad recommended in the build vid and just hot glued it to the foam lid, then tuck the corners in under the hub to hold it in place. It's secure, but not level. So I'll take it off and re-arrange the ESC/power management cable underneath it so the board sits as level as possible. Then re-do the receiver test. Then adjust ACC trim according to the video if it's still drifting toward me.

Thanks for your help!

 

[DDSFlyer]

I would ditto your thoughts on the KK board mount. I tried to soft mount it like Chad suggested, but after I ended up with a little drift, and other various crashes and replaced booms, I decided to more securely mount it to the board. I ended up using foam that had adhesive on both sides to mount it to the frame. I think it made the KK board more accurate and easier to tune.
Other advice about it would make sure that your CG is good, which with your setup should be easy to determine. Then make sure you calibration is on and then off to tuning.
I'd check out the beginning of the KK2 thread on RCGroups (http://www.rcgroups.com/forums/showthread.php?t=1675613) as the tuning videos are all good to start out with.
The last thing I saw in your numbers kind of mystified me...I've heard that the default limits should not be changed on the KK board as they are pretty important to letting the board sort out the corrections. Your Roll/Pitch P limit should be 100 and your I limit should be 20. Just something I saw to point out

 

[slappySF]

DDS Flyer,

Thank you for the advice. I will look around the workbench tonight for supplies and strategies to secure the board to the frame so it's more flat. I suspected that may be part of the issue!

As for KK2 default settings, that's great to know. I will try it with the settings I have now, and see how she does doing more than just hovering 2 feet off the ground (that's really all I could do in my teeny back yard). If it's too hard to fly, I will go back to the default settings as you suggest.

 

[cranialrectosis]

I use zip ties to secure my FCBs.

I cut the single width edges off the foam 'lid' for the 'box' the KK2 came in. You can leave a little extra, but don't cut it too small. Then I line up the KK2 so it sits on the center of the 'lid' and all four edges are flush with the sides of the foam. I then, carefully, push a punch through the mounting holes in the KK2 and through the corner of the foam until I completely pierce the foam for all four mounting holes.

These should now line up with the mounting holes in your Anycopter lower plate. Push a zip tie from the top of the KK2, down through the hole in the KK2 and the holes in the foam and all the way through the hole in the Anycopter body plate. Take a second zip tie and cinch it finger tight up the first zip tie to the bottom side of the Anycopter lower plate.

Finger tight is key. DO NOT APPLY PRESSURE TO THE KK2 AT ANY TIME. Do not push on the corners and do not cinch the zip ties with your pliers. The zip ties should be tight enough to hold your KK2 steady and lightly compress the foam. Too much compression and you risk breaking your KK2 or eliminating the value of the foam. Too little and the KK2 can shift during flight.

When you are done, make sure the KK2 is evenly cinched so it is level.

To remove the KK2, slip a set of surgical scissors under the head of the zip tie below the lower plate on the Anycopter and snip it. Do not pull on it with pliers to get your dykes under the head as you will put pressure on your KK2 if you do.

 

[DDSFlyer]

Zipties are a great idea! I almost thought you were looping them through the holes until I saw the pics, although that might work as well...
slappySF, you also need to try and find an area where you can hover more than 2 feet off the ground. You'll hear the difference in how the copter sounds getting out of its own prop wash coming up off the ground. It will help you tune it better as well. Take it step by step and battery by battery. Also, have you balanced your props yet?