EXI 450 Project: Well... all done but the hanging of crepe...

I finished the 450 build early this evening. Then I took it apart and started over...

I didn't like the pain in the butt position of the receiver. It works well for an experienced builder/pilot. but for me, who expects to change out a few servos before all's said and done, and who will make significant trims in the programming, it was such a pain to access the plugs and nearly impossible to get the bind plug in to rebind.  So I pulled the receiver, and after looking online for alternative positions, decided to put it under the tail servo. The aileron and pitch servo leads barely made it back there. It looks good, is pretty clean, certainly ain't going anywhere and the middle of the heli isn't threatening to end up in the main gear.

Here's a "prototype" photo!  It lacks the grommets as I learned how to shear them in half with fishing line not quite getting how to use it to get the grommets on. I think I have that figured out. And I want to replace one of the ball links that I took from a Blade 400 kit  to allow me to set up the CCPM mixing (its too small by a smidge).

The hardest part of this build, which isn't really over until I fine tune it and hover it for the first time, was the CCPM mixing. It shouldn't have been... but my flybar cage has been sticky since I opened the box. I rebuilt the bearings etc, and it was still sticky. I redid it today as one of my complete start overs (the other being the receiver mod), and its much better. Under spin it won't be a problem. It was frustrating watching Bob's CCPM part 2 and seeing his bubble stay centered, and his flybar not move a hair, while mine tilted with swash movement (better now).   I do think I have the swash set up pretty darn clean though, and am proud of that. I think there is some fine tuning that will need to be done. Right now I have it set up -8 to +8 for pitch in Idle Up. Its -2 to +8 or so in Normal mode.

There as still some things I am still not too sure about. I am not sure the tail setup is spot on.  I have it centered well, but I couldn't figure out how to set the end limits of travel with the gyro, my MKS GY292. Its not one of Bob's gyro vids. So I did the best I could.  I did the tail mod changing to following edge control, and that seems to look good, but we'll see. The DSP75 servos make a lot of noise just sitting there. Its not a buried servo sort of sound, just a hi-pitched buzz, like it jogging in place just waiting to take off. Nothing is moving, and it sounds solid when the servos get input. Its just noisier than I expected.  I'm using metal gear EXI servos on my 250.  I wish I had more confidence in my build, but I know I barely knew what I was doing.

The proof of the heli is in the hover. If I had a good heli builder around here that I knew, I would really like to have them look it over before I fly it, but I am all alone, with you vicarious minions, whose hopes alone I bring with me for that first spin up!  for now, I am scared to plug in the motor leads!

Thanks for your help!  Stay tuned for maiden flight pics/video. I hope it does not end with the hanging of black crepe...

After the new Year I should have my Dynam E-Razor 450 flight ready, and then I will start on my CopterX 250 build.

Challenges, Changes and Gaining Experience!

This build has been a challenge, mostly in those areas where inexperience plays a large part of having to redo installations and setups. In the future I will stick very closely to the order of events, to the smallest detail, in Bob White's video series. Its missing those little details, and the slight differences between the kits that makes for errors that have to be corrected. Experience makes my listening to his vid the next time more illuminating. I wish there was an explicit step by step go-by, would have saved me some time and angst. That being said, I am learning SO much from these brief forays along the wrong path. testing my patience though!

For instance. Bob, using his some many, many years of experience, set up his servos perfectly with his receiver OUTSIDE the frame, right after installing them  (is there any heli he has not built? See the list of build vids on Helifreak.com). Then he put the receiver in the middle of his ship. Well, I thought I had my servos setup properly and buried my receiver in the middle of the heli. Well... I had to swap the aileron and pitch servos plugs, have had to re-setup the tail servo having to remove the gyro lead and put the tail servo lead back on the receiver, set up the servo, and return everything back to gyro mode, and have had to rebind after changing several programming setups. Not easy with the receiver in the middle of the heli! I can't take the main gear out every time I need to rebind, so I struggle to get the bind plug in the receiver.

I also made a ouch mistake of ignorance. If the programming setup is not done, and you turn off the transmitter the heli can spin up! I had just moved the motor wires outside the frame, as seen in the pic. Fortunately no rotor blades, and the wires were outside the heli! Unfortunately I had not yet disconnected the motor leads so the motor was able to spin up.  I was able to disconnect the motor wire sustaining a bruised and cut knuckle, and broke a tail rotor blade. Later read on line that this is a common mistake.

I flipped the ESC so the battery leads come out over the top of the battery holder, and the ESC leads come out of the hole in the nose. The motor leads now come out the front side of the frame. Very easy to reach and still clean.  I wish there was a similar easy positioning issue for the receiver, but I want to keep it protected in the frame. this mod makes it easy for me to disconnect the motor to tweak the servo setup/ESC, etc without the danger of a spin up.

I was worried about the receiver antennae which seemed to be folding back on themselves. I was worried they would begin to fray, and actually found one spot where it had. You can see the small piece of red shrink wrap I applied, fit snug on the receiver and satellite receiver antennae post and covering the most proximal part of the antennae. I like this and will likely do it to all my receivers.

I found that the "manual" online, the only one that exists, for the MKS GY292 gyro very inadequate. I could not find a setup vid or go-by that described how to setup the gyro, or what to set the gain on the gyro at when using the Gear switch to use the transmitter to set the gain. I did use Bob's gyro setup video and I managed to get my gyro set up in Heading Hold with the right gain (using his correction formula for a >50% = HH mode). I am not sure its enough gain... will have to tweak that. I don't know how to set the gyro limits; there is no limit pot on this gyro. I wonder if I do this using the Travel Adjustment settings for gyro? I will be trying that.

Today I have leveled the swash, and need to work on the pitch travel and setup the middle pitch CCPM by adjusting the linkages. I have already programmed the Normal, Idle Up and Hold Pitch and Throttle Curves.  I will program the swash mixing today. Many of the links on my Bell Hiller are not adjustable, specifically the ones from the washout to the flybar cage and the seesaw (inside the flybar cage) to the grips. Looks like I can only adjust the servo to swash and the swash to seesaw linkages. This is today's adventure!  This is pretty much the last step to the build!

EXI 450 Project: Electronics are in!

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I got the electrics in overnight with some adjustments this morning. I wanted to take pics as I went along, but my wife took the camera with her to Atlanta... I just got my hands on it this evening. The electronics look pretty good, but they are crammed in there.  I now wonder what Bob "Finless" White doesn't show us in between steps! I put the ESC under the battery (velcro) and the receiver is in the middle of the lower body (you can see the antenna sticking out. The receiver is up on a block of closed cell foam, the inserts from the blade holder actually, and held in place with velcro. Its difficult to get to the pins... I have to remove the main gear to make any changes, or to rebind the receiver. The satellite antenna is on the back near the tail boom. On this side you can see the butt of the elevator servo.

On this side you can see the gyro aft. I am a bit nervous as I am not sure I can find Finless' video where he describes centering the tail mechanism, and I don't really know how to set up my MKS GY292 gyro even after reading a lot about it.  I had to change the tail servo, moving it to hang from under the tray and adapter, as on top the ball ran into the frame of the heli.  I did get my new ESC programming card and programmed the ESC without any difficulty. I did fry the other card...  You can also see the blue EC5 male connector to the ESC I soldered having removed the red connector.  I have 10 pairs of connectors coming from China soon.

Here's the right side of the fuselage with the gyro in place. You can see the tail servo from here as well.

A close up of the receiver on the right side. the plastic tie is acting as a bulkhead to keep the ESC ferrite ring and the excess wires out of the motor.

I am not entirely sure which plug goes where on the receiver. The easy ones were the aileron, elevator, rudder (the gyro 3 plug), and I used gear for the single wire from the gyro. I plugged the ESC/BEC lead into the throttle, and the bind/battery plug is unconnected. I hope this is right. I initially had the BEC plug in the battery spot, but the motor didn't run and I realized that it was likely supposed to go into the throttle position.

Now I have to complete the swash setup and mixing, the curves, the tail setup with the gyro setup.  I am nervous as this is where my understanding is getting thin. More time with the Finless Bob videos!

I also purchased another heli today, a receiver ready Dynam E-Razor 450 and a Spectrum AR6100E to go in  it. I wanted at least one 450 heli I am sure can fly, and with which I will cry less when I crash it.  This was the 450 heli that first got my attention and made me want to build one. It was on sale at xheli, and now that I have the Dx6i I don't need a transmitter and receiver combo, so could get the less expensive one.

I plan to finish up the EXI 450 build and get a maiden flight this week!  This was a lot of work, and quite the learning experience. Soon I will start on the CopterX 250 build, as I have all the part in hand now.

EXI 450 Project: 3S Batteries arrive, Mods needed

My trick of ordering a US based 3S battery to get my China ordered batteries to arrive worked... The Turnigy 3S 20C batteries arrived from Hobby King, about 3 weeks in transit. They came with a Hobby King connector called an XT60, which looks like a cross between a Dean's connector and and EC3 connector. My ESC had those ginormous red EC like connectors, of which I have none, don't know what they are called, and didn't feel like struggling to find, so I thought I would use EC3 connectors. I drove over to my LHS and bought up a bunch of them. Got home, and since I will be using these same batteries on my 600, decided to go with the larger EC5s I had purchased earlier (need to find a bulk order place...).

The wires were too large for my Burnzomatic butane soldering iron to heat, but I managed to avoid cold soldering the wires, and used the torch to liquify the solder in the pin cups. They went together very nicely, and when I accidently pushed the neg wire into the positive side of the plastic adapter (after carefully checking to make sure I wouldn't), I stress tested the joint trying to pull it apart and the littler mother held tight... Did manage to part the two and put them back where they belonged by forcing a pair of needle nose pliers back up the connector (took very little force, actually).

I also had to change the Sky Charger adapter from the big red ginormous one to EC5 so I can charge the batteries. Charged the first battery with the new connectors and it went fine. The second one was taking too long (about the same as the first, I was just too tired to wait), so I stopped it early to continue later so I could head to bed... I also changed the ginormous red connector in the ESC to the male EC3 (after a quick question on Helifreak was answered promptly), putting the female connector on the batteries as my HF buddies suggested. I found a small comment on a HorizonRC/Atlanta Hobby video that mentioned putting the pins in the male connector from the ESC and the tubes in the female battery connectors.

Once I had a charged battery, I set up the ESC prgramming card that I think is fried, and I think it's fried... Card connected to BEC reciever lead then battery to ESC, and the blue light came on steady, the beeping continued steady after the inital 3 notes, and the lights lit up normal on some lines, a couple on others where only one should be lit, and that beeping went on and on, the blue light never went out, and the card started to get warm. So I disconnected it, tried again, same thing. Its toast, so I tossed it, and will have to wait for the one I think I ordered from HobbyPartz to arrive. I say think because my PayPal went through, but I never got an order confirmation; waiting from an email response from sales.

It was tedious, but its done.

When I get the new programming card I can program the ESC. I took the motor pinion out, too difficult to get to the motor wires. Tomorrow the servo setup and install! I am off next week, so I hope to finish the build and get in my maiden flight then!

EXI 450 Project: ESC Placement

This was a tougher job than I thought because things never quite fit the way they should, but overall it wasnt that hard to do.

In dry running the placement I found that the ESC is a hair too wide for the frame, so its squished in between the plates.The shrink wrap around the ESC frayed a bit, frustrating only my OCD.  Getting nervous with the tight fit and fraying, I looked for other places it might go, to no avail. It was going to have to go there if I wanted it clean, and inside the frame.  I had to squish them motor wire pins a little to get them to fit into the ESC leads, but they are still lock tight. In pulling the black one off, the pin came off the ESC wire; it was cold soldered... I had to re-solder that and re-shrink wrap it. It then took some time to come up with a way to fold the wires back, keeping the ESC motor wires off the motor pinion as Finless Bob warns, and then getting the wires to fold back on themselves to fit inside the frame. The plastic tie I used to hold the Velcro'd ESC and the ESC wires in place could not go alongside the tight fitting ESC, so I had to slant that down a bit. In the end its a pretty clean install.

In this first pic you can see the battery tray as if hinged forward. The blue ESC motor leads come out of the ESC, and fold over it. The plastic tie can be seen, with a piece of unheated shrink wrap around it to protect the wires underneath from vibration letting the tie cut through them. The motor leads (the red, black and yellow ones) lead back into the frame towards the motor.  The BEC wire to the receiver is the white, red and black one, also going back into the frame.

In this pic looking down through the frame at the motor pinion, you can see the flatehead regular 4M screws I had to use for the motor, which shipped with the wrong screws. You can also see same 3 blue ESC wires folding back into the frame, with the battery tray "hinged" back into place and bolted in. The blue wires are well clear of the pinion, even when the motor gets adjusted for backlash against the main gear later in the build.

Finally, in this pic you can see the ESC below the Velcro on the battery tray, with some clear plastic tape I placed to protect the sides of the ESC, and a bit of the plastic tie holding the ESC in place. You can also see a little blue wire in the front inside of the frame, where they connect to the motor wires that come up as the red, black and yellow wires held together away from the outrunner motor with a yellow plastic tie. the receiver wire is the red, black and white wire that is temporarily spewing out from under the motor.

You can't tell from the pics, but the sides of the frame just below the battery tray (the Velcro) bulge ever so slightly. This is the best place for the ESC, where it is in the Align manual, and where Finless put his. It looks pretty good. I just did not want it hanging off the sides, and there was really no way to situate it so the wires at either end could go where they needed to.

Next I will install the servos. I am still waiting on the batteries from Hobby King in China that I ordered on 11/26. Last night, not wanting to delay the servo set up and the ESC programming any further and having no idea when the batteries would arrive, I ordered a battery from Hobbypartz knowing that in doing so I guaranteed they would arrive the next day. Of course, today an international registered mail package came to the post office, which I suspect has the batteries in it, but it will have ot wait until I can pick it up...

I also ordered another Hobbywing/Volcano ESC programming card from Hobbypartz because I may have fried the one I already have when playing with it (I was bored). I attached a 7.4V battery to it and it got hot at the connection and the lights came on like they were supposed to, but were pretty bright (what is it with me and batteries?).  I thought it would be fine, but I should have remembered that the BEC down regulates the voltage from the 7.4V battery to 5V... so I was not surprised to turn the page of the card's manual to read, "Do not connect to a battery of greater than 5V". So, when I did connect it to a 3.4V battery, only the middle three lights lit up. I then watched a vid on programming the ESC, and the host commented on not connecting a higher voltage battery because  "It might fry it...".  Pretty sure I have fried it and not wanting to delay myself further, as before, I ordered one with the battery.

Oh, the lessons we learn that constitute experience.

EXI 450 Project: Tail Servo Fit Problem Solved

As discussed on a previous post, I had a problem with my HSG 5084MG 22gm servo being too small for the tail servo tray. I ordered the Align 18gm carbon fiber servo adapter kit. I had to Dremel out the sides a bit to fit the 22 gm servo, but lengthwise it was fine.

The two screw holes in the plate did not line up with anything on the adapter. I used the plastic "nut" tab seen in the background, which came with the kit, on either end and they stabilized the servo quite well.

To be safe, I Dremel'd out the adapter to allow one screw at opposite sides on each end to prevent the servo from twisting in the tray.  You can see the small silver screws  in opposite corners. I ran out of metal washers, so made a Home Depot run. The only washers I could find that would work actually turned out to be perfect: I found #2 black fiber washers which can be seen in the pics.

All in all, it came out just right.  You can see the "nut" tabs holding the screws under the tray at either end of the servo.

Me and my CB100 #2

Flying the #2 a lot in the apartment here in Meridian. Getting a lot of hover time, small circles. The seizures are rare now days. I'm pretty sure its just a bad ESC and will replace it at some point. Last night my friend Bob came over, and despite having flown great all afternoon, it would not behave! Somehow the servo settings were wrong on the transmitter... not sure how that happened. Didn't figure it out until after Bob left. Curious as I didn't notice in preflight.

Flew a lot today, ran into a table, broke a tail blade off, glad I brought a spare.