Shot this video of an A109 landing at the hospital, across the street.
That is all.
Monthly Archives: June 2010
EXI-450 Helicopter — Build Day 6
FRUSTRATION!!! Tried to fly but all I managed to do was cause the thing to spin like some sort of evil weapon. Despite my best efforts to solve the gyro issue, it was just not stable! At least the P-51 was treating me well yesterday. Even few it behind a long row of trees (accidentally) and it was still upright in the same slight banking turn it was when it suddenly went out of view. Even managed to land it on it’s wheels. Finally some R/C success.
So, going to the oracles on helicopter setup, it looks like the death spin was due to either sub-functional gyro (great..) or some other reason unknown. The gyro is brand new, and it initializes, reads inputs, applies compensation on yaw.. but.. just not working ‘right’.
Here is video my daughter shot while I was trying to sort the thing out.
Not exactly impressive. :p
Respect the Rotor
It’s really that simple. Don’t underestimate the smackdown power of a spinning 450 class rotor blade, even if you powered down the motor.
Sunday 13-June-2010 — After 5 hours:
Monday 14-June-2010 –After 18 hours:
Wednesday 16-June-2010 –4 days later:
EXI-450 Helicopter — Build Day 5
Setting Re-duex.
When I thought I had it all figured out, I learned (in a rather painful way) that I in fact did not. At least no blood was spilled.
So, after a lot of testing with the heli double duct taped to the floor, I have some new settings that visually agree with my very limited understanding of how these things really work. One mental hurdle was figuring how how the Swash mixing really worked. A simplistic view of individual servos on the swash was getting me into a major logic box. It was when I looked at it from a conceptual standpoint, instead of the discrete mechanics, that it made sense. Confused? Join the club!
DX6i EXI-450 Programming Ver. 2 |
||||||
|---|---|---|---|---|---|---|
| Dual Rate & Expo | ||||||
| Aileron | Elevator | Rudder | ||||
| 100% | INHibited | 100% | INHibited | 100% | INHibited | |
| Travel Adjust | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| ↓100% | ↑125% | ↑100% | ←125% | →100% | ↓125% | |
| Sub Trims | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| 0 | ↓10 | 0 | →38 | 0 | ↓16 | |
| Gyro | ||||||
| INHibited | ||||||
| Throttle Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 0 % | 25% | 50% | 85% | 95% | |
| Stunt* | 0 % | 20% | 40% | 40% | 40% | |
| Pitch Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 50 % | 50% | 67% | 82% | 100% | |
| Stunt* | 15 % | 27% | 62% | 80% | 100% | |
| Swash Mixing | ||||||
| Swash | Aileron | Elevator | Pitch | |||
| – 60% | – 60% | + 60% | ||||
| Channel Mixing | ||||||
| Master | Slave | Rate D | U | Sitch | Trim | |
| Mix 1 | Throttle | Throttle | 0% | 0% | ON | INHibited |
| Aileron | Aileron | 0% | 0% | ON | INHibited | |
| Elevator | Elevator | 0% | 0% | ON | INHibited | |
| Rudder | Rudder | 0% | 0% | ON | INHibited | |
| Gyro | Gyro | 0% | 0% | ON | INHibited | |
| Pitch | Pitch | 0% | 0% | ON | INHibited | |
| Mix 2 | Throttle | Throttle | 0% | 0% | ON | INHibited |
| Aileron | Aileron | 0% | 0% | ON | INHibited | |
| Elevator | Elevator | 0% | 0% | ON | INHibited | |
| Rudder | Rudder | 0% | 0% | ON | INHibited | |
| Gyro | Gyro | 0% | 0% | ON | INHibited | |
| Pitch | Pitch | 0% | 0% | ON | INHibited | |
| Revo Mix | ||||||
| UP | DOWN | |||||
| Normal | 0 % | 0 % | ||||
| Stunt | 0 % | 0 % | ||||
DX6i EXI-450 Setup Ver. 2 |
||||||
| Reverse | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| Normal | Reverse | Normal | Reverse | Normal | Normal | |
| Swash Type | ||||||
| CCPM 120° | ||||||
| Throttle Cut | ||||||
| POSITION – ACTIVE | ||||||
| Dual Rate Combination Assignment | ||||||
| Dual Rate Switch: – INHibited | ||||||
| Power Setting | ||||||
| B-US 247 | ||||||
| * NOTE: I have set the Stunt settings for my own safety, not for actual stunt flying. If you use those settings you’ll end up with a bird in the ground, but at least it’s less likely to go full-throttle without you expecting if, if you do something really stupid (like me) and flip the mode from NORMAL to STUNT without thinking. | ||||||
Not many photos were taken today since this was mostly transmitter programming, a little out of control flying and working on dialing in the Gyro. Still spent more than a couple of hours hacking away at understanding all there is to creating a BASIC setup for a good hobby helicopter. Now I have a better understanding of why RTF helis like the MadHawk typically don’t ship with an BNF (Bind-and-Fly) version. The amount of customer support they would have to deal with would quickly consume the fairly narrow profit margin.
Perhaps I’ll have the bird in the air this next week. For now I need to call it a night and get ready for another exciting week of computer programming, project management and cat wrangling.
EXI-450 Helicopter — Build Day 4
The fourth day of construction starts with preliminary radio programming. Based on A LOT of information floating around on the web, I’m going to start off with the following settings for the bird. The manual for the radio itself is 139 pages, 80% or more of which are specific to the two primary programming modes, AEROCRAFT and HELICOPTER. I’ve said it before, I’ll say it again. The advances in R/C radios and equipment over the last 10 years is staggering.
NOTE: It turns out some of these preliminary settings were DEAD WRONG – Those in red were changed. See DAY 5 Setup for the corrected values!
DX6i EXI-450 Programming |
||||||
|---|---|---|---|---|---|---|
| Dual Rate & Expo | ||||||
| Aileron | Elevator | Rudder | ||||
| 100% | INHibited | 100% | INHibited | 100% | INHibited | |
| Travel Adjust | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| ↓100% | →100% | |||||
| Sub Trims | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| 0 | 0 | |||||
| Gyro | ||||||
| INHibited | ||||||
| Throttle Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 0 % | 85% | 95% | |||
 |
||||||
| Stunt | ||||||
 |
||||||
| Pitch Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 50 % | 50% | 67% | 82% | 100% | |
 |
||||||
| Stunt | 15 % | 27% | 62% | 80% | 100% | |
 |
||||||
| Swash Mixing | ||||||
| Swash | Aileron | Elevator | Pitch | |||
| + 60% | ||||||
| Channel Mixing | ||||||
| Master | Slave | Rate D | U | Sitch | Trim | |
| Mix 1 | Throttle | Throttle | 0% | 0% | ON | INHibited |
| Aileron | Aileron | 0% | 0% | ON | INHibited | |
| Elevator | Elevator | 0% | 0% | ON | INHibited | |
| Rudder | Rudder | 0% | 0% | ON | INHibited | |
| Gyro | Gyro | 0% | 0% | ON | INHibited | |
| Pitch | Pitch | 0% | 0% | ON | INHibited | |
| Mix 2 | Throttle | Throttle | 0% | 0% | ON | INHibited |
| Aileron | Aileron | 0% | 0% | ON | INHibited | |
| Elevator | Elevator | 0% | 0% | ON | INHibited | |
| Rudder | Rudder | 0% | 0% | ON | INHibited | |
| Gyro | Gyro | 0% | 0% | ON | INHibited | |
| Pitch | Pitch | 0% | 0% | ON | INHibited | |
| Revo Mix | ||||||
| UP | DOWN | |||||
| Normal | 0 % | 0 % | ||||
| Stunt | 0 % | 0 % | ||||
DX6i EXI-450 Setup |
||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| Normal | Normal | Normal | ||||
| Swash Type | ||||||
| CCPM 120° | ||||||
| Throttle Cut | ||||||
| POSITION – ACTIVE | ||||||
| Dual Rate Combination Assignment | ||||||
| Dual Rate Switch: – INHibited | ||||||
| Power Setting | ||||||
| B-US 247 | ||||||
Once the Transmitting programming was complete, continuation of wire routing was undertaken. A quick trip to the electronics store for a bulk pack of tie wraps and large diameter heat shrink tubing got things back underway.
With the larger diameter shring tubing, I was able to put add it to both the motor and ESC wiring harnesses where they run along or through the frame. Better safe, adding a few grams of weight, than watching a helicopter catch fire because of a short.
7 wires from the Gyro are protected with the shrink tubing, where they will run through the frame. This is before using the heat gun to shrink.
My plan to apply shrink tubing in all areas where wiring is on or near the frame is working out well. The combined Gyroscope and elevator servo wire groups are protected where they will run between sections of the rear frame.
Preparing for first adjustments to blade tracking. Battery, canopy, ESC, motor all connected. Radio is not yet mounted because final tail servo setup has to be completed before finishing Gyro wiring and final radio installation.
Gyroscope and elevator servo wiring runs completed and secured. Radio will be mounted inside the frame just below re-entry point of the wiring harness. Shrink tubing covers wiring were it is near or in contact with frame.
More wiring work completed. Final securing of motor wires and ESC control harness (center to right), and primary AR6200 Receiver box with control wiring installed. Final radio installation has to wait for final servo setup, travel tuning and Gyro preliminary configuration.
30A Electronic Speed Control (ESC) secured to nose of frame. ESC is place are far forward as possible to help balance aircraft.
At this point, the blade tracking can be adjusted. Here is a video of the three runs in the shop to check and adjust blade tracking. One blade required 2 full turn reduction on connector length, the other blad required a single turn of extension to get blades tracking equally.
VIDEO:
EXI-450 Helicopter — Build Day 3
I only spent a couple of hours working on it tonight. I spent most of my time cooking for the kids. Tonight was no gourmet meal. However about 1/2 the time tonight was spent doing prep for tomorrow night. With 5 prime cuts of beef soaking up my proprietary beef rub overnight, it should be the basis of an enjoyable meal tomorrow.
So, with not much time I didn’t think I’d get much done. And, looking at the photos you’d probably ask how I spent 2 hours doing that. One word: soldering. One of the typically hidden, overlooked and far to often poorly done. Just for reference, here are some tips from Ask.com [LINK].
First, let me back track a little bit. As mentioned in yesterday’s post, I’d not been able to purchase a battery locally. Today, I took a chance and shot over to one of the really old-school hobby shops. It’s right next to the PLU campus in Parkland. As with all recent trips to the hobby shop, it wasn’t a cheap trip. I did, however, get a battery with a really nice mAh rating. The C level is fairly low (surge capacity) but for some training flights it might keep me out of trouble. And the price was pretty decent (about 1/2 of what other places were going to sell me much smaller battery for).
You can see in the photo here, the battery is a lot larger than the ‘big batteries’ for the MadHawk300. They look pretty wimpy in comparison (for reference, the MadHawk battery is the silver one marked ExceedRC on top).
It is only going to take about 3 1/2 hours to charge that battery with the wimpy little charger I have right now. That does not allow for much flying. :/
Back to the soldering story. The first step was to solder the Deans connectors onto the speed controller (aka ESC). Soldering the speed controller was a breeze. Good quality wire bound to the Deans connectors quickly. That was easy!
What I spent probably an hour fighting with are the cheap micro-hair stranded aluminum wire on the battery I picked up today. It’s one of those things you just can’t see when you purchase them, since they typically already have some sort of connector affixed. Sadly, not the connector type I want to use. Here is a close up of a Deans connector I’ll be using.
But I did get the soldering completed, after destroying one set of Deans connectors doing it. Quality of the joints are highly suspect, but they seem to be mechanically sound (tested). Voltage check on the battery before and after affixing the connectors did not indicate any measurable voltage drop due to resistance in a bad solder joint.
Here is a photo of the final production, on the ESC. I don’t plan to post a photo of the battery connector and soldering work. It’s an embarrassment. But after 3 attempts, one destroyed connector and starting to run out of wire for the battery, it’s going to have to be sufficient.
With a 3-cell battery, connectors attached to battery and speed controller (ESC), I was able to finally power up the AR6200 long-range receiver and get it bound to the DX6i radio.
One of the nice things about the DX6i, is it’s 10 model memory. Plus it has the ‘safe model’ feature. If you accidentatly forget to select the right model file for what you are flying, the RX and TX won’t talk to each other. RX binding data is retained with the model configuration. The concept here is to keep you from firing up your cool Delta Dart ducted fan jet, and taking off, only to find you’d left the transmitter configured for a conventional aircraft. That can create a REAL mess when you grab a stick full of elevator. The DX6i won’t like kind of mistake happen.
With power on the system, plugging in the servos allowed preliminary servo horn positioning and fine tuning with the sub-trims. Just in case I lose my programming on the bird, I’m going to document the subtrims and other settings on this page:
| Sub-Trims EXI-450 V2 & Spektrum DX6i | |||
|---|---|---|---|
| Throttle | 0 | Aileron | +40 |
| Elevator | +32 | Rudder | +23 |
| Gyro | 0 | Pitch | 0 |
So, here is the current state at the end my tonight’s short work session. As you can see, there is a lot of work left to do. It still does not even look much like a helicopter yet.
EXI-450 Helicopter — Build Day 2
Spent a couple more hours working on the 450 last night. It’s coming along nicely. Today I didn’t need to grind anything.
A couple of the many tasks required to get this thing in the air, is balancing the main blades and applying Loctite to all metal to metal fasteners. To accomplish this I needed some very small metric hardware and a new tube of low-power Loctite. A lot of people are using Blue Loctite 242.
I don’t think it’s the proper compound for fasteners of the size we’re using, so purchased a large bottle (all they carried at the store) of the Purple Loctite 222.
The place I like to go for such things is Tacoma Screw (there is one local in my town, about 35 miles from Tacoma itself – for this I’m glad). It’s a jobber style shop with top-notch customer service, curious people behind the counter (by that I mean they like to talk about what you are working on) and always friendly. I picked up a pair of German Philips #0 and #00 screwdrivers:
Also picked up 100 2mm washers:
And finally, a long 2.5mm bolt and nylocks for making a home-brew pour-boy blade balancing rig:
I ran one of the nylock nuts down on the screw, about 2/3 of the way. Placed the blades on the bolt and ran down the other nut, just making them snug. I chose the nylock nuts because I knew that they would stay put once I achieved the snugness wanted. A few extra pennies spent to save a lot of potential frustration later. You learn these sorts of things being a gearhead for nearly 4 decades.
The frame on the EXI-450 Plastic V2 is made of a stamped metal (you know, I think it’s aluminum, but I’ve not confirmed that), so some of the edges are rather sharp. To prevent the cutting/chaffing of wires where they exit the frame, I placed a small bit of high-strength tape (red) on the frame and then places a heavy duty heat shrink tubing over the wire bundle and applied heat to shrink with a heat gun, which works orders better than a lighter. You can get a cheap heat gun at Chinese places like Harbor Freight for around $10.
Here is the reciever I plan to use for this helicopter. It came with the Spektrum DX6i transmitter I purchased last month, and have been using with the ParkZone P-51 and Blade CX3. Not in this photo is the 2nd remote antenna/receiver that provides a very long range capability.
Installing the linkage balls on servo horns was next. The idea here is to make sure the link bars are as perfectly vertical as possible when installed on the servo, so some trail and error is required to select the correct hole to mount the balls. In this case both of the forward servos were able to use the last hole. You’ll notice that the balls are mounted in ‘reverse’ so the ball is on the servo’s side of the arm. Once they are all installed and photos taken, the reason for this will be clear.
Unfortunately, not all servo placements allow for such cut-and-dried installations. To get as close to pure vertical actuator alignment, you sometimes have to get a little fancy with the servo hardware. Once again, out comes the cheap Harbor Freight heat gun to apply some ‘persuasion’ to the nylon horn. After determining how much offset I needed, it was made very hot and then adjusted.
I think this makes it a little clearer why the adjustment was made and how it all turned out. This is the pitch cyclic primary servo.
The fly bar on a Bell-Hiller head is critical to smooth and stable flight. To get the fly bar properly setup, the first thing that has to be done is make sure it’s absolutely centered. Measuring with a caliper seems like a pretty accurate method.
Larger photo of the Bell-Hiller rotor head, typical to R/C helicopters.
Unlike yesterday, I placed the ‘calling it quits for the day’ photo at the end of this post.
It’s looking a lot more like a helicopter now! I still need to get some important things before I can go much further, the most critical of which is my batteries! I think I mentioned it in the last post, being unable to source a suitable battery at the local hobby shop, soooooooooooo yet another package of stuff is on the way. I’m sure I could have save $30-40 on shipping if I’d spec’d out my needs better ahead of time. For someone that is such a stickler for planning, I didn’t do a very good job of it for this project so far! :p
EXI-450 Helicopter — Build Day 1
I’m excited to be building this bird. I will say though, it’s a fair bit of work! Might be little much for a beginner getting into a hobby. I’ve been building models so long, I can’t exactly recall when I started! 4 decades of building is coming in handy here!
Perhaps it’s bad form, bad marketing, bad writing. Whatever.. I really don’t care, but here is the end photo from yesterdays work:
Yes, it took several hours to get to that point. It’s harder than it looks. Especially considering these kits do not come with ANY instructions. Thankfully, Will (owner of MikeysRC.com) has taken his time to document 15 10 minutes videos on how to construct one of these helis. I Just completed video #6.
Following are some snapshots I took during the construction in case you find the need to keep reading.
Future fixes for Madhawk300, but first, unpacking the EXI-450
Yes, it has arrived! It’s here, and I unpacked it this afternoon. Not only that but I shot a little video of it (can’t resist) and I got over what you can get, online, for 25%-50% less than the typical ‘beginer’ helicopters sold in the local stores. Or, even online.
I’m talking about the Blade CX3 (about $200) and the MadHawk300 (about $130).
What you see in the video was under $150 delivered. But, only a small portion of that was the actual helicopter itself. Granted, you need to build it (which is what I spent some time doing today) and a few more parts (which racked up the rest of the cost). But.. the parts are vastly superior to those in the other example birds, and they can be obtained or replaced at most local hobby shops that carry even basic R/C aircraft.
So, here it is. About 5 minutes, shows you what you can get.
In retrospect, I’d wished I had just gone straight into the 450, as some people advised me to do, after I became comfortable with the Proto CX. Which, is still flying very well to this day. Small but tough.
Now, I have not totally given up on the Madhawk 300 concept. I think I’ll eventually fix it up and let the boy practice on it. He’s getting pretty good with the foamy P-51, and with the Proto CX. So.. once I get the Madhawk straightened out, I think I’ll use it for training / beginners and general mayhem when the 450 is being repaired, which, I suspect it will be when I fly my first collective-pitch R/C heli.
Mods another member of the R/C community used to resurrect a Walkera 180D (same basic heli as the MadHawk 300) into a really air-worthy bird:
CB180Q Conversion to Brushless
8g Outrunner – brushless C10 (2S)- 180 Serie
Tail Gear Holder from Q for Brushless direkt drive
26g Outrunner -brushless C20 around 4000 KV
pinion 16 T(metal) Modul 0,3, hole 2,3mm
20A ESC for Main-Motor
12 A ESC for Tail-Motor
Gyro WK-016 Gyro 8g 4-6VRX 2801PRO
TX 2801PRO
good Lipo around 1200 to 1500 mAhNOTE: He even provided a video to go along with it: [VIDEO LINK]
Sometimes it seems you can’t catch up. More Madhawk300 frustration.
So, the replacement blades are just about here for the MadHawk300 FP heli. Awesome. Except, yesterday the dang thing flipped out, suddenly went to full throttle while I was getting ready to swap out the batteries.
It did the ‘Chicken Dance’ on the park bench, snapping off parts the tail rotor. Radio throttle response did not help, it idled down and was just sitting there vibrating wildly (due to broken tail rotor). Carefully reaching under I unplugged the battery.
Swapped the new battery in, got the TX and RX talking to each other… but what now? No throttle!
So, I now have two shattered main blades (replacements arriving today), broken tail rotor ($4.00 which I’d have to mail-order) and now.. neither motor is spooling up!
On the workbench this morning I checked the motors and radio. Seems the RX is no longer sending voltage signals to the motors. Great… why did it do that? Well, a good 6 channel DSM2 receives is about $35 so I checked on the price to replace this thing.
WTH?? Really? $50?!?!
Oh come on now! Worth $15, maybe. Ugh.. more parts. At this point I’m chasing my tail on this thing. It was only $100 new, and 1/2 of the price for the receiver? Might as well just buy a new one and use this for parts! Honestly, I liked the way it few, it was fun, docile and a good trainer, even if the range was HORRIBLE, which I thought maybe I’d fixed by moving the receiver further from motor.. but.. it freaked out and crashed before I could range test.
I’ve read many people doing upgrades to make the thing really reliable. Sounds interesting for certain! But.. then, why toss more good money after bad? Shouldn’t I just chalk this up to some good training and park the thing?
I mean.. for the price of the MadHawk300 I could have bought a EXI-450 AND TX/RX for about the same price!
Then I could get replacement parts locally. Now.. the above also needs:
– motor
– rotor blades
– ESC (electronic speed control)
– Li-Po battery
But it’s also easily upgradable.. with stuff like this, a full CNC rotor head and tail, plus some spare blades:
Or, as my final plan for the EXI-450 I’m waiting for, a scale rotor head:
Update: 9-June-2010 — EXI-450 is here!
And of course you can get really nice scale bodies very inexpensively for the 450’s, especially when compared to the proprietary bodies for other cheaper birds. Here is a short like from just one online retailer:
Factor in cheap proprietary electronics, motors that notoriously fail (tail motors) parts that are not available in any local store, batteries that are a strange size… and you have an exercise in frustration as soon as you run into a snag. And even if you are an expert flyer, you’ll run into a mechanical failure, or electronic failure and voila.. the questions about WTF have you done begin.
So, I’m really REALLY looking foward to the arrival of the EXI-450 kit this week. I’m really bummed that I have nothing to fly right now. 🙁 But at least with the 450 if I break something I *can* get a local replacement part!
Conclusion:
Would I buy a MadHawk300 or Walkera 180x bird again. NO!. I was warned about quality early on, and I chose to ignore that advice of one vocal expert, compared to the many voices singing it’s praises. Well, guess who was right?
Will I fix it at some point? Maybe. But certainly NOT with factory parts. I might turn it into a learning experiment to see what I *can* do with it. But… to what end? I don’t know. The $$$ is better spent on a 450 or 600 class bird instead of patching together what is not basically an expensive paper weight.
Upside, if there is one, is that the radio that came with it might be able to be used as a simulator controller with a $10 cable. 🙂 Maybe I’ll pick one up on the way to work and see what happens.