Tag Archives: r/c

Helicopters, Radio Control

EXI-450 Helicopter — Build Day 2

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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.

Loctite 222MS 'Purple' thread locker.

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:

A pair of good German screwdrivers.

Also picked up 100 2mm washers:

Pack of 2mm washers. Always good to have some washers on hand. This case $1.50

And finally, a long 2.5mm bolt and nylocks for making a home-brew pour-boy blade balancing rig:

Cheap balancing rig. Less than $1.00 in fasteners and an old vice.

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.

Close-up of the balancing operation. This worked very well!

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.

Heat shrink tubing applies to servo wires near body exit.

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.

Spektrum AR6200 receiver I plan to use in this build.

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.

Setting up the servo horns and linkage balls.

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.

Having to get a little creative for the pitch swash servo horn.

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.

Modified horn test fitted in frame.

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.

The flybar must be perfectly centered in the rotor head, so measure twice, move once is the mantra.

Larger photo of the Bell-Hiller rotor head, typical to R/C helicopters.

Bell-Hiller rotor head, with flybar (forground). Main blades not installed.

Unlike yesterday, I placed the ‘calling it quits for the day’ photo at the end of this post.

Progress report - End of Day 2. Looking a little more like a helicopter.

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

MORE PARTS! Along with 3 450 class batteries, I'm getting a good charger!

Helicopters, Radio Control

EXI-450 Helicopter — Build Day 1

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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:

Result of a few hours of contruction. EXI-450

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.

3500kv brushless motor mounted
Motor adjusment bolts. Locktite applied.
Tail drive belt, adjusted to proper tension.
Using grinder to open servo openings, required for some servos.
One of the cyclic servos installed in frame
2 of 3 cyclic servos installed. Hot glue used to hold nuts for install.
3rd of the 3 cyclic servos installed (rear)
3 cyclic servos installed, starting to check control arm alignment.
Helicopters, Radio Control, YouTube

MadHawk300 hover practice, however I killed tail drive.

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OK, this is frustrating. 20 some odd flights and the thing’s rear motor is going out. There is a dead spot in it, so, somethings on a hard right yaw, the motor does not start back up and it spins into the ground, breaking… more stuff.

I did manage to get in some good practice on the day before though:
WATCH VIDEO: MadHawk 300 Hover Practice

So I’ve started to research updates to this rear drive issue, and the lack of power in the main motor (seems to be losing power, turning freer than it should.. seems like it cooked too, too much hover practice and not enough cooling airflow?).

At any rate, I found this info on the Walkera 180 (same heli, different brand name) that might get me a really sweet flying ‘learner’ heli for friends and family.

I got this info off the RCGroups forum [LINK]:

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 4-6V

RX 2801PRO
TX 2801PRO
good Lipo around 1200 to 1500 mAh

Here is another thread [LINK] with similar solution. It might be overkill for what I want to do.

Another idea on 'fixing' the MadHawk300 shortcomings.

Helicopters, Radio Control

Blade CX3 nearly meets it’s demise – out of action

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Yesterday evening, was a great evening to fly. Not much wind, very very light rain and nobody at the ‘fly zone’ to accidentally kill. When you are unleashing an 8 year old piloting a P-51 Mustang model, these are things you need to consider. To be honest, he’s better at flying it than I am.

While the P-51 was zooming around the park, sometimes slamming into the ground nose first at full throttle (foamy planes are really good trainers) I took up the two Helis for some practice.

First up was the MadHawk300. The CX3 and Foamy P-51 are both bound to the same transmitter, so I could not fly the CX3 while the transmitter was in use. I’d done some tuning on it, adjusting the motor. The last failed flight attempt was dashed when on run-up the main pinion began to slip at 1/2 throttle, keeping the heli from getting off the ground. I’ve since lock-tited those motor motor screws.

It few well. Adjustments I made to the swash gave me some really nice control. At higher speed and throttle, helicopter flight dynamics are not at all intutive to a guy that’s used to fixed-wing models. But it still went well, with a couple of hard landings, no big deal.

Then, it happened. While at the east end of the part, close to one of the Pavilion buildings, the tail suddenly started to swing wildly, it accelerated upward, then nosed rolled right and slamed into the pavement at near full throttle, doing quite a number of the landing gear and main rotor blades.

Madhawk 300 with broken landing skid.

🙁 Nothing that was too tough to repair, but I didn’t have the wrench to replace the rotors on site.
Toasted main rotor blade on the Madhawk 300.

At this point the battery on the P-51 was running low. I recouped the transmitter and started to fly the CX3. It was flying very nicely. Nicer than the Madhawk in fact! Zoomed round the park, turned on and off the model navigation lights, did some high speed passes, landings, just some fun landing.

Then, it happened.

Right in the same place the MadHawk had trouble, the CX3 started to go crazy, and started to go into the TBE death spin. I tried to regain control but no luck. It accellerated upward, then nosed over and went straight down, nose first into the ground at full throttle. 15′ was more than enough room for it to gain some momentum.

CRUNCH. It was not a nice scene. The following photos are after I attempted a field repair on the fusalage to fly again. Unfortunately it would not happen since the radio and transceiver were no longer talking to each other.

Once home, I tore down the heli (I’m getting far too good at this) and discovered that the radio receiver took the full-force of the crash. Part of it’s case was ripped off and one of the dipole antennas was missing. Oh oh!

Helicopter on the operating table. Trying to get TX and RX to talk to each other

Removed the plugs from the Spektrum AR6100e receiver in the heli, plugged in the 3-in-1 mixer, checked response. The mixer would not show it’s green ‘lock’ signal. It was not until later that I noticed that the signal lock LED on the AR6100e’s front was actually missing. But it was at that point I realized, that not only was the body smashed, the lower section of the frame mounts for the battery are broken, but the receiver is, completely, shot. I’ve broken at lot of things crashing R/C aircraft, but never destroyed a receiver. It’s at this point I’m thankful for using Spektrum R/C equipment. Replacements are 1/2 that of Futaba or JR radios. Still, it’s a $55 part. Ugh. 🙁

Close up of AR6100e broken receiver (unmounted) and 3-function mixer (mounted)

I don’t want to order a replacement receiver unless I *know* that’s what is broken. So I dug up the AR56200 full-range receiver I have, wired it in to the heli’s remains, and tested. Viola. 3-in-1 mixer lock and receiver lock. It’s a go. Now I just need to decided where, and when, to buy a new receiver. In the mean time, she’s out of commission.

At least I still have the MadHawk300 to fly. And if I crash that into pieces, well.. I’ll just say I have a contingency plan arriving for that soon as well. ):

What's next!?!

Helicopters, Radio Control

Digging this MD500E Scale Helicopte vid

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Found this on the XHeli.com Facebook page. Love the sound of these things.

I’m anxiously awaiting the arrival of my EXI-450 from XHeli.com, hopefully in the next week! Then I’ll have to build it. Then learn to fly it. Then learn how to repair it after I crash. Eventually I want to add a body kit like this, and replace the stock plastic parts (ordered plastic on purpose, about 1/2 cost and I plan to replace it as noted) with one of these:

HAC 4 blade Rotorhead for 450 class Heli

Radio Control, Technology

R/C micro Li-Po batter charger testing

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It’s come to my attention, that the little battery chargers that came with the various helicopters, might not be working up to par. Taking longer than I want to charge is one thing, but not charging properly is another entirely! A recent visit to the hobby shops indicated that it’s common for them to fail. But, they should be easy enough to test to see if they are applying a full charge by the simple use of a multi-meter.

Thus, I dug up my trusty Fluke (it must be over 25 years old now), put in a new 9v battery and started some testing.

All batteries here are Lithium-Polymer (Li-Po) 2-cell 7.4v batteries. 2 of the batteries tested are for the Blade CX3, the other for the Madhawk 300. Here is a link to the chart I created to document the batteries I’ve used.

  E-Flite Battery Charger ExceedRD Battery Charger
Exceed-RC 7.4v 1000mAh 8.4v     8.4v    
Tenergy 7.4v 900mAh 8.43v     8.43v 8.43v  
E-Flite 7.4v 800mAh 8.43v 8.38v   8.43v 8.43v  
Hyperian VGX3 #1 8.43v          
Hyperian VGX3 #2       8.43v 8.43v 8.44v

Results

Testing so far indicates that the chargers, although slow, are doing the job. One battery, the E-Flite 800mAh seemed a little down on power during the 2nd cycle of the test. It might already be suffering some degradation of performance. If that’s the case, it’s pretty pathetic. I plan to run each through at least 3 charge cycles to get a decent dataset.

Helicopters, Radio Control

CX3 repaired and flying again!

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The Blade CX3 is repaired and flying again! The $22 aluminum swash plate repair, actually has the thing flying better than it did right out of the box!

E-Flight OEM Plastic Swashplate E-Flight Upgrade Aluminum Swashplate

Here is a 3 min video of first test flights in the studio, and finally my 8 year old attempting to fly it, for the first time, outside! The crosswind was playing havoc but he did a pretty good job of keeping things together. I think he’s going to be a good pilot some day.

Even though it’s a Toy Co-Axial helicopter (a $200 “toy” to be exact), with the upgraded part, it’s a joy to fly. There is something so therapeutic about an activity that puts nice big genuine smile on your face. And in the end, what price is too high a price to pay for some joy? 🙂 Even though I’ve “outgrown” this helicopter in about 1 week of intense practice, I still want to keep it around, and even put some more upgrades on it! Such as this cool LED strobe kit I’ve seen on the web. Here is a video from a guy that I think, sells the best of them:

Here are a few pics flying it outside, just before dark. Shot with an f2.8 200mm lens, 50D camera set at ISO1600 and roughly 1/30th second shutter speed. Despite the slow speed and high ISO, I think the shots are work posting.

Blade CX3 spooled up and ready for takeoff.

Blade CX3 spooled up and moving out. Still in ground effect.
Blade CX3 after battery change, ready to go again.
Blade CX3 in flight.
Blade CX3 flies overhead.
Helicopters, Radio Control

Good times, bad times, upgrading and crashing the CX3…

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Good times. The Blade CX3 is one heck of a fun bird to fly.

The first update today was to add the factory heat sink for the main motors.

E-Flite CX3 heat sink

After removing one of the motors, installing the sink was pretty simple.

Heat sink install 1/2 complete

Motor re-installed and bolted back into position:

Motor re-installed.

The fame looks a little naked without the body installed. But it does not take long to put it back together, and ready for flight.

E-flite CX3 with body removed.

A little time lapse video of re-assembly:

Ready to enjoy some indoor heli flying fun.

Completed bird, and Spektrum DX6i flight controller

Well, it was, until the plastic factory swash plate decided to separate. I’d been fighting with adjusting the swash links most of the evening, after putting the heli back together again. I thought that maybe I’d bent a servo link rod during the heat sink install, so I worked on adjusting the cyclic/swashplate links.

Trying to stop a hard forward and starboard liftoff, and full rear cyclic would barely have any effect. It was not until an hour or so later I noticed that the plate where the servos attach was separating from the bearing and main rotor shaft. Duh. This explains why 2 directions worked great (pushing up on the plate) but the opposites failed (pulling down on the plate, but the upper bearing remained in position, thus no control. No control, but one check of an exciting crash!

The official term for this is TBE (toilet-bowl effect). Not fun. There is quite a discussion of the problem HERE. Once I discovered the problem, it was a matter of deciding how to solve it. There are a couple of solutions.

First of which is a pretty inexpensive factory replacement part.

Stock replacement swash plate.

Second is one of the CNC or cast metal solutions from E-Flite (the original manufacture) or other sources. Research indicates that the E-Flite is the one to buy.

E-Flight aluminum replacement swash plate.

Fortunately, there are plenty of other heils in the shop ready to fly.

Blade CX3 (left), Exceed-RC Madhawk 300 (right)

Helicopters, Radio Control

Maximum Geek-out. R/C + iMovie = ???

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It was bound to happen, taking the next step and actually taking 2 minutes to edit my little ‘movies’ (really a personal video diary of my learning to fly and crash little flying machines). Here are the first two that I actually was able to load into iMovie and convert.

First is the Revel Proto CX. My micro counter-rotating blade heli: I cut a bunch of worthless time (more worthless that this video, hard to image but true) out of the middle and focused on the ‘good stuff’:

Next is video of the bird #2, the Blade CX3.

EFlite Blade CX3 - MD520 Notar

I had just unpacked it, installed the training gear extensions (the funny orange balls) and bound it to the Spectrum radio that came in the ParkFlyer HobbyZone P-51 foamy. That was a nice little treat.

Blade CX3 - MD520 Notar

For the most part it worked great. Here 90% condensation of about 25 minutes of actual flight time with the CX3. This was my first attempt.

However, yet again, I managed to mangle the landing gear after a few panic throttle chops as it got a little close to big steel things that would break it. :/ Back to the hobby shop for MORE stuff!

Blade CX3 replacement landing gear. I left them 1 on the rack. At least they are not TOO expensive!

And finally, here is my repair video. First semi-successful attempt at time-lapse with the Canon S1100 micro-camera. The hardest part, I thought, would be learning how to do this with iMovie ’09. Nope, after some prodding around it turned out to be pretty simple. Sadly the camera was doing some sort of zoom-in and zoom-out madness. Site down before watching, you might get ill. Some are going to wonder about the music. Did I shot the video with this music in mind. NOT! Who’d try to shoot video like this, outside the brain-dead corridors of intellectual bankruptcy one finds in L.A. or N.Y.? No, but the frantic into to a good German industrial metal song just… WORKED! I only hope YouTube does not over-dub the music with something totally lame out of their music library, as I’ve heard they have started to do this.

UPDATE!

YouTube send me this message today. Hopefully they don’t over-dub the music. But, when you’re using a free service, their hardware, their network, it’s not a stretch to concede they own that copy of it.:

Your video, Eflite Blade CX3 MD520N (Notar), may have content that is owned or licensed by UMG.

No action is required on your part; however, if you are interested in learning how this affects your video, please visit the Content ID Matches section of your account for more information.

Helicopters, Radio Control

Fleet is expanding (heli 3 and heli 4)

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It’s beyond obsession at this point. I’m going to need a 12-step program.

Yesterday I converted some old ‘iron’ at the gun shop to one of these at the hobby shop (I don’t have a need for a piddly 9mm anyway). This is Heli #3:

Blade CX3

As I type, the batteries are charging for the Heli, and the transmitter.
Blade CX3 battery packs and DX6i transmitter charging up.

I saved $35 by buying the BNF (Bind-n-Fly) version of the kit. The Spektrum DX6i I already obtained is compatible with this (and the P-51 too as a matter of fact).

Then this morning, I received shipping confirmation of ‘Heli 4’ from the on-line retailer XHeli.com. This is my first time ordering stuff from them. What surprised me was that within 24 hours the merchandise was picked, packed and on it’s way!

Thank you for shopping at XHeli!
Your order’s shipping label is generated and is scheduled
to be shipped on 05/21/2010 via UPS.
EXCELLENT!!

New Heli and parts on the way!

I’m having it shopped to my office in Tacoma since I don’t want to have it sitting on my porch all day at work. Plus, there is ALWAYS someone there to sign for it, since we are 24×7 shop. Fast FAST shipping and great prices. We’ll see how it all works out.

This is what I’m expecting. 🙂

Exceed MadHawk 300

ESky Flight Training System

Now, I already had this one here. Which now I think I paid WAYYYYYYYY too much for:

RealFlight Basic

I’ve been practicing with it for a week now. It’s OK, and it has some cool planes in it, but the helicopter physics seem… weird. Really weird. And I completely irritated that I had to build a WINDOZE box to use the thing! Luckly I still had an old (circa 2006) Dell computer floating around, and it’s running Windoze XP (which the new software needs too.. got lucky there), but the hardware was not up to the task. Wish I’d known that when I bought it. So $100 for the software kit, then I had to toss in another $80 to get a decent DX9 compatible video card for the OLD PCI (not enhanced regular old PCI) interface, AND 1GB of memory for another $50. (poor thing only had 128MB in it.. not enough to even open the program.
So almost $250 to construct a flight simulator with a used computer!

Then.. then, I find this recommendation lurking around one of the Heli message boards. Heli-X.

It’s written in Germany AND it runs on Mac OSX!!!! So of course I downloaded it (it does not come with any controller, BUT the controller from RealFlight works PERFECTLY!). It’s also fairly pricey too at $50 Euro, and it only handles Helis BUT the physics in the trainer are SO much more realistic, at least to me.

Here is a shot of the simulator (sorry, I don’t have the controller hooked up at the moment so it’s just a shot of one model on the ground). It’s pretty good, and I’m learning that Variable Pitch, fixed throttle flying IS A LOT more intimidating that fixed pitch variable throttle!

Screen Shot of Heli-X

When will this end?