first build thread: lessons and learning to follow...

[Motopreserve]

So... in anticipation of the Northeast winter ending at some point, and my penchant for crashing, I decided to go ahead and balance a bunch of props ahead of time. I was getting pretty frustrated with the cheap props I had bought (a bunch from Hobby King in my first order, and some GemFans that looked a bit better). Problem was, I kept having to put a LOAD of CA on the hubs to get them balanced. So much so that I began to fear that they might fly weird from the additional mass on the one side of the hub.

It seems people go round and round about the TopFlite vs the Du-Bro balancers, and I was NOT in the mood to spend more money on a tool I already owned, but I just pulled the trigger on the Du-Bro to compliment my TopFlite balancer. I began to get a little frustrated by the imbalanced 'stops' that hold the prop onto the TopFlite shaft. Also, the legs of the TopFlite make it almost impossible to get level, and are made of cheap plastic. I am having a hard time understanding why something apparently meant for precision is cobbled together from cheap plastic parts - other than the shaft and the magnets. I will be making some aluminum stops on the lathe so that I KNOW they are balanced - but I just got fed up, and bought the other brand to see if it works best...

 

[jbrumberg]

Scott- I have been sorely tempted by that Du-Bro balancer; especially so since wifey is still out of town, but I must stay strong on this. Although one cannot truly predict human behavior; I already "know" what would be wifey's reaction if she saw two balancers :hororr:I did however buy some more Gemfan and Hq props. There is safety in numbers. I just do not like the way those "hunchbacked" Gemfan hubs look when the are supposedly "balanced". I am going to try that aluminum tape suggestion, once I find a cheaper roll of that stuff.

It will be interesting to see how the two balancers compare side by side and prop to prop. Good luck

I do not know about this next shot of Winter cold and winds with the next series of systems. I did go out this AM and fire up the tractor to clear out all that 2" of snow we had for a "couple" of reasons. Maybe a slight improvement in weather conditions to allow for some limited flying later this week... maybe. The engine block heater, injector pre-heaters, battery charge assist and my own "special" diesel fuel additive mix and the tractor was still cold and laboring for awhile. I want to keep an area clear for take offs and landings so to speak.

 

[Motopreserve]

Ill let you know how it goes. I think Mike is going to have both as well. I need to see what he was talking about with raising the dubro with some shell casings????

i stumbled onto yet another tip that showed checking the tracking of the prop - basically seeing if the 2 blades run in about the same spot when spinning past a marker tied to one leg. The gemfans I had on the balancer at the time was NO WHERE NEAR tracking correctly.

I ordered the APCs so I'm done with props until the decent ones show up. I have the crappy ones for crash testing - and I'll get these new ones balanced nice when they arrive.

 

[coreyperez]

Moto & J:

I've got my 550 almost together and my Honey Badger should be here in about a week. I've also got another friend here in Korea who is getting ready to purchase one of the boards. I ordered x2 KK2.1's (one is here) other is coming. I also have a Multiwii here. I'm curious if you guys have a good couple of links that will really help me get schooled up (quickly) without having to read through a bunch of nonsense.

Thanks for any help you can provide!

Corey

 

[Motopreserve]

For which board do you need the info? KK2.1 or the Multiwii?

where did you get the Multiwii board? There are a few different types, but they all operate on the same basic principal.

 

[coreyperez]

I've got both. Hobby King.

SEE! I didn't even realize there was a difference between different types (same principal)!!

Corey

 

[Motopreserve]

The software from yours will be pre-loaded or is available from the Files section of the product page. It depends on the version of the board - But you can go to the wiki for multiwii and read a ton about it - and how to modify it.

Youll need eves the free Arduino program to do any mods or for snooping around and becoming familiar with it. Also, depending on what version firmware is on it (2.3 is the latest, but still has some bugs - but has waypoints), you can get the appropriate GUI to make switch assignments and adjust PID.

 

[jbrumberg]

Corey- I must have seen a 100 KK2.0 taining videos. I think the KK2.0 and the 2.1 set up the same. I believe these are two of the better ones:
http://www.rcproreviews.com/kk2-0-flight-control-board-v1-6-firmware/ , http://www.multirotorforums.com/showthread.php?7283-KK-Introduction-and-Tuning-videos

Good Luck,

Jay

PS: There was another one, It was like 15 minutes long, but it was pretty good. I am sure that I will run across it. I'll link it when I find it.

 

[slow_jun]

Hi,

Your build thread is very informative, planning also t build a similar quad with tarot gimbal for go pro and also later with a FPV,. just wondering what is your mixed flight time with your setup? you are using 3s right single only right? targeting a mixed flight of 15ms with your setup, will this be possible?

thanks in advance.

 

[Motopreserve]

Hey Jun. glad you found some useful info. I have only run a single 5000mah 3S battery so far. Unfortunately I have not had enough time in the air to give you a accurate answer. During my initial testing I was landing with a safe amount of battery charge remaining - just being overly cautious. I was definitely getting over 8 minutes on my timer. But it was basic flying - and more hovering and slow flying than anything aggressive.

The Gimbal w/camera will add to this weight considerably. So not sure how much time you'll get. I think it's a fine balance between capacity of battery vs weight of battery. Also, not overdrawing with unnecessarily large ESCs.

I think ink your best bet is to head over to eCalc to swap components around to find a good balance for start. It's not exact, but it helps with understanding the interactions between components.

I too too have been researching FPV a lot. But I think I'm realizing that I could get away with some type of video camera downlink - since I really just want to frame my shots.

Good luck!

 

[mbowser]

Like Moto, I haven't had enough air time to really dial in the flight times but I am using a single 4000mAh 3s (Zippy Compact) battery and according to eCalc I have 5.8 minutes mixed flight time (1350grams total weight). I believe the hover time was 11.5 minutes. This past week we put on a battery alarm to warn at 3.5, but it seemed that it cut the time significantly and there was still plenty of battery left. I think we have to start actually using a timer, but we keep forgetting. Once I started ignoring the alarm, we had at least 7 minutes flight time, but without time I can't confirm.

-matt

 

[jbrumberg]

For hovertime eCalc appeared relatively accurate based on flight time and remaining battery capacity which I measured "hot". eCalc is not the only predictive program of which I am aware, but it is very popular and used by a lot of smart and experienced people which I am not.

I will be curious as to logging in some real flight data someday. This sitting around and playing around with RC stuff indoors is starting to get dangerous. I saw a picture of a really neat motor test bench at RCG. I should rewire my Tx LiFe batteries. I am thinking of upgrading my Tx with hardware and firmware. All these things that could get me in even more trouble.

I got my HQ SF props from Got Heli RC today in AZ. I ordered on Friday. That means I should get my Gemfans tomorrow. An unfortunate afterthought that will cost me $2.95 for postage.

 

[Motopreserve]

I agree. This sitting and waiting is getting annoying and expensive. I might as well move to a warmer climate. I'd have more data and it might be cheaper.

just got got another couple inches and the wind kicked up. No respite in site...

Time to get cracking on the scratch-built quad.

 

[jbrumberg]

All kinds of weather craziness right before, during, and now with his new cold weather system. A dusting of snow, sleet, then a brief mix, and back again to snow. Wind increasing all the time as the temperature drops... Disgruntling weather to say the least. Of all those little projects that I mentioned I really do not need to do any of them, and as the old saying goes- "Don't fix it if it's not broken.". As for the Tx- I do not really need the backlighting, fancy graphics, expanded programmability, expandability to other protocols, etc. at this point in my learning curve. I could see myself really screwing up the Tx or its existing firmware.

Better days and weather will come. It's a statistical inevitability.

 

[Motopreserve]

Yep. I think sitting tight with the Tx is probably a good move. Play it safe and balance so e props while you have the time. Or something else productive that's proven to fix and not break.

 

[slow_jun]

Thanks guys for the quick reply. im really digging this stuff but by brain is always full . hahha... sorry for the question but am I correct to believe that the multiwii can do RTH and hold Alt and also do Waypoint right? sorry haven't searched those function yet, I was set to get the KK2.1 but when I saw your setup then . boom!!!!.... need to rethink again.. hahaha

 

[Motopreserve]

Jun,

multiwii version 2.2 definitely does RTH and altitude hold. Also a bunch of other stuff. The newest version is 2.3, and adds waypoints. I have not installed it yet though, so I can't vouch for that myself. It seems people are having decent luck with it from what I've read. These boards are not for everyone. It certainly will take more effort than a KK2.1.

Realize that multiwii takes some research and there are more variables to fine tune. But at the end of the day, it offers a ton of functionality for the money. If you decide to go this route - I would definitely suggest going with a Witespy version, because he pre-programs the firmware for exactly what you order - and it's cheap. Then you can make changes as you become more comfortable with the programs and interfaces. Many people complain about the shipping times (he can get backed up with orders), but for something this complicated, I think it's worth it.

If you're excited to get flying as quick as possible, I would suggest the KK2 (you can always upgrade), if you have more time on your hands and like the challenge - try multiwii.

Scott

 

[Motopreserve]

Not sure if I mentioned it here - but both Jay and I ordered Turnigy D2830-11 1000kv motors from Hobby King, and they arrived with stickers on them that said 1100kv. Very disconcerting, since I had ordered another set of 4 before actually looking at the sticker close enough to notice the discrepancy. Are they 1000kv or 1100kv? There is no way to tell inside the motor, no other markings of any kind. Seems like a slight difference for the rig I'm running, but since I ordered some from the USA warehouse, and the next batch from China, I was worried that they might be mismatched...

I contacted HK directly, and after MANY emails back and forth, finally got confirmation that they are in fact 1000kv motors, and just the sticker was printed wrong.

In the meantime, I had ordered a set of 4 motors from Witespy, who has some made for him that he markets under the "house" brand. These are only marked by his company name "Ready to Fly" on the side. The specs looked pretty good (NMB bearings, 220W, wires directly from the windings). They are 1050kv, with the prop adapter/holder that screws (you choose 2 CCW and 2 CW adapters so they tighten correctly for the motor spin) directly onto the bell. This is something I have been looking for after hearing all the imbalance nightmares with the collet-type adapters, and also the unnecessarily long shaft (bent one already!) that came with the D2830's.





At $18, they are double the price of the Turnigy's, but I am OK with that if they last and run well. And getting motors that have the screw-on type adapter is a huge plus for me. I have been researching Sunnysky motors, which seem to get good reviews for the price. Of course I'm looking for T-Motor style performance and reliability, for a cheap price, which may not exist...

 

[jbrumberg]

As I learn more about this quad build I am sure that my motors will be upgraded. I definitely do not like those long motor shafts and those nacelle connectors, but they seem to work for me for the present. Knowing what I do not really care for does at least provide me a sense of direction.

 

[Motopreserve]

I dont regret getting the cheaper motors to start. I think we all knew we'd crash a fair amount while getting up to speed. But the new motors might be a decent interim choice for me - better prop security and no extended shaft.

Jay,

What are you referring to when you say "nacelle?"