Just arrived!!!
My latest toy box (or box of toys) arrived during the conference this week. I’ve had a lot of time to work on building this machine, but I did manage to get some HXT-900 cyclic servers and a general test/fix mockup completed. ! I still have to order several parts before it will fly.
Finally, it was time to see if this thing would fly. And, if I can fly it!
This outing was my best yet! 3 full packs flown, no crashes, no rotor strikes, and only 1 really hard landing! I (of course) shot some video and uploaded it to my YouTube bucket.
Not never exciting to watch, it was pretty exciting to get it off the ground without flying back into it out of control! This is pretty fun stuff! Plus the gear-head part of me really loves all the micro-mechanical parts and seeing how they function together and make it fly!
Tonight, I’m picking up where I left off yesterday [LINK], while I listen to some awesome local High School Radio (KNHC).
Sunday nights from 6PM -> Midnight is Industrial and Alt music show called ‘On the Edge‘. Reminds me of a similar show that used too broadcast on KFJC out of Foothill College in the Bay Area. Most of my good German Industrial music collection was the direct result of hearing it on that show.
Back to the Overhaul
I’ve been doing some research today on blade balancing. Picked up a couple of new tricks, talked to a few of the local experts and I’ve come up with what I feel is a comprehensive, but not exhaustive (aka anal retentive) balancing strategy. Here is my take on this VERY IMPORTANT task:
First off, getting some good tracking tape has proven to be a major challenge for me. Today I solved that problem, thanks to advice of a local flyer. He’s been using Monokote (I’m quite familiar with the heat-shrink version of it, having first used it almost 30 years ago). I picked up a high-vis red and contrasting orange in the adhesive backed variety.
I don’t plan to balance the other 4 sets of blades I have tonight, just the set I’ll be using for the final run-ups once I have the bird back together.
The first step in balancing, is to find the COG (Center of Gravity) on each blade. I did this by rolling each blade on top of a spare flybar rod (it’s about 3mm in diameter) until I found the balance point. Once I did that I marked it with a permanent marker. This is done for both blades. The purpose of this is to determine how much balance weight you need to add to get the blades balanced our along each blade itself. Ideally you take the lighter of the two blades (if you have a scale that’s easier to determine, otherwise your normal blade balancing fixture will tell this tail), apply weight in the right locations to get both blades to have the exact same COG. I’ve done this already, the top blade has a little clear plastic tape used to weight it on the right side. Here the COG’s are in the same location on both blades.
Next I’m going to take equal pieces of the adhesive backed monokote, and apply a different color to the tips of each blade. Make sure the size of the monokote you apply to each is identical. They must also be applied in identical locations. Here is what it should look like *before* performing the final balance.
Next, set up the balancing rig and dynamically balance out the blades. Any weight, if required should be added to the light blade at it’s COG (which is why it’s marked across the pitch). Even though these blades are very close in overall balance, one blade does need a little bit more, to fully balance it out.
Once balanced, I moved back to the process of rebuilding the head. I had a lot of experience with the V2 head, but not the older Version 1 head that I had to buy parts for (no V2 parts available locally or online from the plethora of vendors, odd really). Interwebs to the rescue! I found an original ALIGN 450SE (v1) build manual with the exploded view of the V1 head!
Somewhere in the box of parts is the main head, and all it’s associated bearings.
There are a lot of parts that go into the grips alone! That’s 6 bearings, 2 spacers, 2 washers and 2 bolts, not to mention the 4 o-rings (dampners) and the feathering shaft itself (already installed in head).
Having the instructions made assembly straight forward and quick. It took longer to write this pragraph and take the photo, than it did to put together, install, locktite and tighten the grips. They seem very firm and turn very smoothly. A HUGE improvement over what I was attempting with the hybrid V2 guts and V1 components. I knew better, but I wanted to see how close I could get. Not close enough. At any rate, here it is, assembled.
The next step is to attach the rest of the upper head’s running gear. The flybar seesaw holder was a little problematic. Gunk in the bushings had it binding up. Finally resorting to application of some firearms cleaning techniques (and fluids) cleared up the gunk. Re-application of all locktites was of course required after being exposed to solvents. Added a little CLP to the bushings to keep the running smooth. Pitch arms were next and those when back together without drama. This is what I have now;
It was finally time to bolt the head to main shaft, insert flybar, line up the washout shafts and block, hook up swash coupling links and get ready to finish the top-end rebuild of this bird.
While upgrading parts, I decided to swap out the temporary Blade 300 flybar paddles (smaller, top) for the larger genuine ALIGN 450 parts. They are basically twice as thick, have actual airfoils and weight 8.8g, compared to the Blade 400 units which are 2.7g. The orginal EXI flybar blades come in at 4.7g. I tossed them out. One was not factory drilled for the flybar, so I just sorta hogged it out during original construction. Turns out that alignment of that bore is really important to the overall flight characteristics of the bird! They are gone, just in case I forget why they are no longer in use, and put them on something. I’m better off with the flimsy B400 paddles than one that is not drilled properly. Many lessons in these little things.
Installed, centered, measured, re-measured, checked for square, re-measured down to .001″ inch. with dial calipers. I’m sure how to get it any more accurately constructed than this! With the blades installed, it’s time to perform the first run-up and blade tracking test. Really, about 9 hours of work comes down to the this moment of truth. Fixed, same or (gulp) worse?
This video contains the first run-up, before blade tracking was adjusted. Next was post-tracking adjustment. Overall vibration has been reduced significantly! With the replaced bearings and slightly slower head speed the entire things sounds healthier too. Another view in the video displays the blade tracking, and finally a fully assembled bird is run up to 3/4 throttle. A test of the throttle cut and auto-rotation flare action is also examined for function.
Everything looks great and ready for another test flight! Local time on the Pacific Coast here is 23:07. A little too late for test flights. The plan is to give it some air time after work tomorrow.
One other thing I noticed, was that flybar action is much smoother since I completely tore down the head and rebuilt it.
The upside of all this, is that I’m 100% confident I can repair any damage done during a crash, including a full frame up-reconstruction. At some point this fall I’ll probably swap out the metal frame for a V2 carbon fiber setup (about $30). That will drop quite a bit of weight off, and going to a CF tail boom will also shed some weight. The less the entire thing weighs, the less power it will use to remain aloft, which equates to lower operating temperatures for bearings, and longer flight times with the same batteries.
Now, I rest.
Since I was not 100% certain of the proper method of blade balancing, I’ve started up this page. You see, until 9:00AM this morning I was certain how to properly balance blades. However, after reading the ALIGN Trex450SE instructions, which contain this diagram, I’m not at all certain.
Up until now, I had placed the blades trailing edges flat on a table, then tightened the balancing tool, and placed it on the jig. The objective was to have the trailing edges of the blades perfectly level. Here is what it looks like:
I hope you can see the difference in how I placed the blades together, compared to to what the Align manual suggests. Here is a closeup to help illustrate how I used to do this:
Compare this to using the ALIGN documented method:
As you can see here, not only does it appear quite different, so is the result! Using this method, my blades are out of balance. Or, are they?
Now, I’ve gone out and searched and consulted with the great oracles on this subject (the R/C discussion groups) and found the following:
On one of the most helpful sites I’ve found on the web, Mikey demonstrates the blade balancing using the same method, that seemed intuitive to me. Here is a screen shot from the video:
Checking another forum, I found the following this post that discusses first locating the COG (Center of Gravity) on the blades and marking them. Or balancing the COG on the blades so they are the same blade-to-blade, THEN getting them in dynamic balance:
http://www.rcgroups.com/forums/showthread.php?t=878885&highlight=blade+balancing
Hm. there seems to be MUCH more to getting a really great balance on your blades than meets the eye! With the vibration issues I’ve been happening, I’m going to do everything I can to provide as stable a main blade balance as possible.
What is most clear at the point, is that I have A LOT more reading to do. PART 2 will follow once I decide on exactly how I will be balancing my blades. The question of the afix orientation of the blades perists, even after I find the COG of the blades.
This link here looks to be the most concise explaination of a balancing method. [LINK]
I’ve had a few good flights, and few bad flights with the N450V2A. After locating a nasty wobble and some incorrectly manufactured parts, I’ve torn the bird down to just about the bare bones and have started a re-construction.
Starting here with this picture, I have already performed the following.
Replaced the Main bearings in the main bearing blocks. One of the old bearings had a bit of a ‘notchiness’ to it so I tracked down some replacement parts, including two pairs of original Align factory main bearings (5x11x5mm). $6.49.
They are installed at the top of the frame, and in middle, just above the main gearset (in blue). The main gearset has already been replaced with at genuine factory Align part AGNH1218 $22.99
The original Pentium 30A ESC (Electronic Speed Control) was showing signs of overloading and causing in-flight resets! In defense of HobbyWing, it looks like I was running too steep a pinion on the main motor (I’ll get to that later). Regardless, I wanted to make SURE I did not have to learn auto-rotation landing in my first few weeks of flying. So I purchased a new genuine Align 35A ESC with Governor, PN 35ABLESC GOVMD5VBEC RCE-BL $53.99. It’s installed high on the frame now, where the battery would normally be located. I did this to help ensure good air flow along it’s heat sink.
As mentioned, it turns out the that original 13T pinon which came with the EXceedRC Alpha 400 63N18 motor is not an appropriate selection. It was suggest that I run either an 11T or 12T pinion by several people online. The local hobby shop had a pretty knowledgeable flyer behind the counter, and suggest a 12T would make a big difference. It’s also the suggested pinion for the factory Align Trec450 V2 (of which mine is a clone). Having already ordered an 11T pinion, I purchased the 12T. Original 13T is on the right, new 12T Align part on the left:
The motor itself might be OK. I’m going to re-use it for now. Another is on the way from Hobbypartz.com price about $20.00. The pinion is only firmly mounted on the shaft, since it will have to be precisely adjusted for main gear engagement once I re-install the motor in the frame.
Next I went about trying to get the main bearings and main shaft running as true and consistent as possible. The bottom bearing has some manufactured in lateral play, nothing I can do about that. But I did manage to snug up the shaft to bearing interface with some very light knurling of the main shaft where it contacts the lower bearing. Additional play looks like it will come out with a slight ‘cocking’ of the upper bearing. Just enough to produce a natural tendancy to run straight. I have plenty of bearings now. One of my next objectives will be to take the extra bearings I have to an expert bearing distributor and see if a higher-quality bearing is available in the same dimensions.
After all that work, the main shaft finally looks like it’s running true. The dial indicator is still picking up some movement, but it’s about 1/2 or perhaps less than it was originally. I think I managed to take at least a little play out of the main drive system, and that makes very hopeful for some major flight improvements.
Taking all these parts off, I think it wise to re-check the swash plate level, just in case it something got bent, twisted or otherwise tweaked. Placed the 450 swash leveling took on the plate, and it was dead on! I ordered the tool from XHeli.com (it’s an EXI too) for around $3.50. Well worth the investment. When I checked my ‘by eye’ leveling with the tool I found I was pretty far out. Sure it’s a fair bit more labor to tear down the head to use the tool, but having such a core component as close to perfect spec as humanly possible seems like a wise use of one’s time. Maybe it’s not, but I did it.
Having conquered my fears of the main shaft, time to rebuild the rotor head from the swash pate up. First thing I want to tackle is the top of the head, sort of going in reverse order. It turns out my latest blade grip purchase, to replace the broken grip, wss of the WRONG PART. My model is a Version 2, and the parts I got, unbeknown to me, were Version 1. Barely close, certainly not the cigar. Now today I did pick up a full compliment of Version 1 parts. Combined with the plastic Version 1 head ($7.99) and 2 pairs of grips($13.99) from the other day, I should be able to assemble a very tight and very functional main rotor head. My ideal scenario would be to re-use the original allow EXI head (left) instead of the new Align plastic Version 1 head (right).
It turns out the the V1 head (right) and the alloy V2 original head (left) are identical in width, and the ID of the feathering shaft ($7.99 for three) holes are also identical. The only difference (beyond material) is a more pronounced shoulder in the V1 head. Fit wise though, they tested out (to the best of my abilities) the same! This is very encouraging! All I need to do now is figure out how the V1 head systems is supposed to go together!
It’s about 1:00AM now. No need to work all night on this thing. I’ll pick this another day, maybe tomorrow, maybe I’ll go ride a motorcycle instead.
After fighting with the gyro for a day, I finally cleared the programming on the DX6i and re-did ALL of it. I learned a few more things along the way. This is the final, current configuration that actually let me fly! I won’t pretend to say this is an optimal or even suggested setup, but it’s the one I came up with. Maybe this helps some others get their stuff off the ground.
DX6i EXI-450 Programming Ver. 2 |
||||||
|---|---|---|---|---|---|---|
| Dual Rate & Expo | ||||||
| Aileron | Elevator | Rudder | ||||
| AIL D/R 0 | 100% | INHibited | 100% | INHibited | 100% | INHibited |
| AIL D/R 1 | 100% | INHibited | 100% | INHibited | 100% | INHibited |
| Travel Adjust | ||||||
| Note: You need to move the sticks to access both travel directions, this was an important lesson! | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| ↑100% ↓100% |
↑125% ↓125% |
↑100% ↓100% |
←125% →125% |
←100% →100% |
↑125% ↓125% |
|
| Sub Trims | ||||||
| Throttle | Elevator | Gyroscope | Aileron | Rudder | Pitch | |
| 0 | ↑30 | 0 | ←17 | →42 | ↑63 | |
| Gyro | ||||||
| 0 (flap-0) | 1 (gyro-1> | |||||
| SW-GYRO | 60.0% | 70.0% | ||||
| Throttle Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 0 % | 25% | 50% | 85% | 100% | |
| Stunt* | 0 % | 20% | 40% | 40% | 40% | |
| Hold | 0.0 % | |||||
| Pitch Curve | ||||||
| Low | 1/4 | 1/2 | 3/4 | Full | ||
| Normal | 25% | 50% | 67% | 82% | 100% | |
| Stunt* | 15 % | 25% | 25% | 25% | 25% | |
| Hold | 0% | 10% | 10% | 10% | 10% | |
| Swash Mixing | ||||||
| Swash | Aileron | Elevator | Pitch | |||
| – 60% | – 60% | + 60% | ||||
| Channel Mixing | ||||||
| Master | Slave | Rate D | U | Sitch | Trim | |
| Mix 1 | INHibited | |||||
| Mix 2 | 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 | Reverse | 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. | ||||||
Following the re-build of the tail setup, removed gyro.. server testing.. reprogramming.. it all led up to the first *real* flight of the 450. Even in some pretty good wind!
Despite the bluster, the heli flew, and the gyro seemed to hold to any heading I set! This was FUN!
Despite bouncing off the pavement, I had a big fat grin as I walked home. I’d built the helicopter, I’d flown it, crashed it and flew it again. Now it’s time to learn to *really* fly this thing! 🙂
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
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.
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.
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:
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.
