Wednesday, December 24, 2014

Hangar 9 Sopwith Rebuild Complete

With the arrival today of the new prop shaft from HeadsUp RC (the fastest shippers I have ever frickin' ordered from!), I was able to adjust the motor for centerline (no offset), install the prop, check CG and call her done! She is looking really good, and I can't wait for first flight.


 

Chip's Frankenplank

Chip Young got a fuse from an estate sale, that needed a wing. The chord was a perfect fit for my old Eflite PulseXT 25e wing, so I gave it to him and he's installed it. It looks marvelous! Th margins and the tail shape make me think this is a model of an MX2 (UPDATE: Turns out Chip says its a SIG 4 Star, a 0.40 glow model). Will be fun to see it fly! Well done, Chip!

 

Monday, December 22, 2014

Warping the Sopwith Wing

Worked a little on the Sopwith today. The more I thought about it the more I realized I really need to unwarp those wings. It's sloppy, non-aerodynamic, and adds too many lift variables and drag.

This is the pre photo, where you can see the bottom of the top left wing (on the right) and the top of the lower right wing (on the left). That top wing is really wacky.

 

 

I needed to twist the wings in opposite directions, brining the back of the left wing up and the bottom right wing down. I made a set of guide wires to induce and hold the wing twist. This is the guide wire I installed under tension on the left wing outer strut. It pulls the top wing leading edge down, and pulls the bottom left wing up a touch.

 

This is the wire on the right wing, pulling the front edge of the right wing up and the back of the top one down. You will notice that the right and left wing wires run in opposite directions.

 

The top wing is straight all the way across!

 

And the post pic. Both wings are straight. We'll see if the wires hold in flight, they are under a little tension. I suspect the tension will lessen as the wood begins to shift to the new stresses.

She does, by the way, lean a little to her right. This is the way the landing gear, which are flexible, settle. There are rubber bands acting as shock absorbers on each wheel, and the landing struts are mobile, able to flex side-to-side. She likes to lean right. I may work on this, not really sure what I can do.

Waiting for the prop adapter. I also wanted to do the guide wires, but some of them snap under load, so I thought some high test fishing wire? I may just start using the wires I have (a set of replacements I bought long ago).

 

Sunday, December 21, 2014

Hangar 9 Sopwith Rebuild

I started work on the Sopwith Camel today, cleaning up and patching the fuse, resetting the servos And control arms to make everything as zero/ninety as mechanically possible. This puppy has got some issues.

I found that the prop shaft is ever so slightly bent. Any offset will cause significant vibration, so I removed it and ordered a new one from HeadsUp RC. This motor is pretty ginormous, not as big, I don't think, as the one on the MX2. If I cared I could check the specs... I will be flying this 6S. It has a 100A HobbyWing Pro ESC, but it's not high voltage, and 6S is more than enough power.
 

I installed the wings after working the fuse. These wings are warped, always have been. The flaws seem to balance out.

 

You can really see the warped wings; looks worse in the pic than it really is. The upper left (on the right of the pic) and the lower right (on the left) are warped in opposite planes. The elevator is also warped on the right, and I will likely need to rebuild it. Right now I have it clamped, but I don't expect that to work, it never does. Tomorrow I will rebuild it. I just don't have the time, skills or supplies to unwarp the main wings. They were warped like this when I first flew her and it balances out. It probably is a contributor to her poor ground characteristics on take-off.

Waiting for the prop adapter, and I need some heavy gauge leader wire from a fishing shop so I can restring the guide wires. Then we shall she how she flies!

Friday, December 19, 2014

From Our "It's Always Somethin' " Department

Working on the Trex 600e Pro rebuild this afternoon, and it was brief, hence the title of this post...

Took the worn main shaft bearing blocks out of the heli. The bottom one was terribly worn, in fact an edge was actually damaged (I knew that...) and I discarded it, the top one was fine, but I will replace both of them. Pulled the new blocks out and when I went to install the bottom one I noticed it was too short. Dammit. Turns out it's from the standard Trex 600 and measures 48mm, not the Pro, which apparently is wider at 50mm. I don't want to McGyver this so need the right parts.

The one on the left is the original, the one on the right the new "too small" block. I ordered what I believe to be the correct size.


I turned then to the tail boom assembly which includes the power take-off assembly, the torque tube shaft and bearings, and the tail control assembly. When I pulled the torque shaft out I found one bearing. No bearing "holder" block. And I like two bearings, so... Back to the order and ordered a bearing holder and bearing set (it comes with two of each). Good thing I left the order open. The stock build requires only one, but most builders recommend two asymmetrically set to prevent vibration harmonics from developing and transmitting to the tail. I set that aside, and went on to disassemble the tail control assembly. I replaced the bent tail shaft, cleaned and re-lubed the bearings and controls. I couldn't get the tail torque tube mushroom gear bearing off the gear, and since it was unworn, undamaged and functioning fine, I decided to leave it in place. Tail assembly done and ready for installation.

According to the return policies of the Align Trex Store I need to have returned the part 15 days after I bought it back in July. I just opened the parts box yesterday, some 6 months later, so that ain't happening. I just ordered the replacement parts; maybe they will at least give me some store credit.

So the Trex 600e Pro project is set aside for a couple of weeks as I wait for those parts, the holidays and some work days to pass. This heli won't be ready until after the new year, and even that is sure to be delayed because there is always somethin'...

 

Thursday, December 18, 2014

Rebuilding the Trex 600e Pro

As I noted, I completed the rebuild of the HDX 500se and she is ready for flight testing, possibly as early as tomorrow. She was one of my best flyers before her frame failed in flight and then the whole seizure thing. But those things are resolved!

Back in Mississippi this summer, sometime in late July I think, I was flying my Trex 600e Pro when the elevator control rod separated from the ball clevis and she performed a jaw dropping flip from thirty feet, ass over teakettle, landing hard on her gear. It snapped her landing gear and ripped the tail boom off, fractured the main blades, but the frame was intact and unharmed. It was an impressive crash and I would have sworn I blogged the incident but I can't find the entry. I mentioned that I had noticed the ball Clovis was loose and needed to be addressed when I was in the middle of another repair, and I never got back to it. I missed it in preflight, launched, got up to altitude and initiated a turn. As I was coming out of it, BAM! It was over in an instance. Someone asked me if I did it because it was spectacular 3D, but I immediately recognized what had gone wrong, and on post crash the clevis was unscrewed, not ripped, off the elevator, and the motion it did in flight was clearly full up elevator. I took her home and stripped off the broken bits, ordered the new ones, and packed them away as they arrived as it was the week I moved back home to New Hampshire. Some of the last parts arrived here, and I set them aside. I didn't fly or work on much as I was in a bit of a funk for the next couple of months, but since I started my new job I am renewed, flying and rebuilding everything.

I pulled out all the new parts and inventoried them.

The intact main frame and the inventoried parts. I put the new gear struts and skids on today. Tomorrow I will start with both sets of main bearings, which were going bad when I bought her, then set up the tail power take-off, torque tube, and tail assembly, which I had to completely disassemble. This will be followed by the main rotor and CCPM, etc. this may take several days. She too was an excellent flyer and I am sure she will fly as well again!

Step one!

Tuesday, December 16, 2014

HDX 500se: Mystery Solved. I think.

I have been dealing with an electrical glitch for a year that I haven't really just sat down and solved. I have tried some simple things, like the ESC, the reciever, swapped out servos... Nothing seemed to make a difference.
Short vid of the seizures.

Earlier this week I thought I had figured out that it was an amp draw issue, but I remained suspicious that this couldn't be the case as nothing changed to draw more amps. That being said, I ordered and today installed a 5amp voltage regulator. For giggles I changed the receiver again from a Spektrum AR 610 to an Orange DSMX receiver from HobbyKing. I love these receivers and have never had any problem with them; that being said I put Spektrums on my expensive aircraft.
I removed the ESC and splice soldered in the leads from the voltage regulator.

I secured the leads to the main power leads with wire ties and taped over the soldered sections. I used Dual Lock Velcro to secure the regulator to the ESC. It will fit nicely underneath.


Installed the ESC back in its original position, with the voltage regulator underneath, inside the frame. You can see the Orange receiver slung on the outside of the frame. This was the only place I could put it and keep the short antenna wires well exposed. The red Velcro strap secures the receiver wires out of the way of the mechanicals. I balanced the tail blades. I fired her up and the seizures were still there.
I decided to change out the gyro. I had spun her up with the gyro not installed and would swear that the seizures continued. I installed the only gyro I have, an Assan GA250 MEMS gyro from HobbyKing. It's a pretty basic MEMS gyro, works pretty well. I've again, never had any problems with them, but prefer the Align gyros. Curious as I have had several Align gyros fail... Fired her up after programming the gyro, and wow. No seizures, no vibration, no wagging tail. Wowser. Another bad Align GP790 very expensive gyro.

Balanced a new set of main blades and installed them. Tomorrow or so I will recheck the CCPM programming, then give it a spin up! She was one of my best flying helis, so I hope she flies like she did before all this BS with the bad gyro.

UPDATE (5/24/15): Took her out back to hover her and... that damn seizure is still there. The only thing I haven't changed is the motor. That's next. She held great with the Assan gyro, but her rotor disk kept twitching making control difficult.

Eflite Piper J-3 Cub Certified for Flight Testing

Today has been a busy day. There will be a post after this on on my continued adventures trying to stop the seizures on the HDX 500se heli, which I frickin' finally have done...

Finished the work and set up on the Eflite J-3 Cub! Finished installing the windows, installed the wings and set up the servos system. I decided that the 12x6e prop just didn't give me the ground clearance that I want, so I changed to a Master Airscrew 10x8 that I think used to fly on an Eflite PT-19 Cornell I used to have, a couple of years ago. I think I've crashed a couple... I have one NIB and will likely start on it after the Sopwith Rebirth Project. I don't think you can get them anymore. I didn't recheck the watts, probably should. I suspect the 2" in pitch balance the 2" in length, but I made that up.

Windows on, awaiting wings.
 
 
Wings and struts done.
 
 

I had to add 1/2 oz to the nose to make her just a bit less tail heavy. Now her CG is spot on. I guess we'll know for sure on maiden flight.

 

I put slightly larger tires on her. I like the rugged look of these treated DuBro tires for this plane. I also have the skis I can toss on in place of the wheels.
 
 

The stock taile wheel is that measly thin POS. I replaced it with a more manly tail wheel. I had to fabricate the entire tail wheel strut to support it.

 

She now rests with the rest of the flock, awaiting a decent flying day!

 

Next plank project is to rebuild the slightly damaged Sopwith. Between the cat that jumped off a ledge onto the hanging plane in my old apartment in Jersey, and the move damage, she will take some time. There were also likely some initial build things I will change. She was a great flyer, once one got past the wicked prop torque on the ground that pulled her hard left, gone the moment she left the ground causing a hard right turn (or was it the other way around?). In the air she flew like a massive WWI plane.

Sunday, December 14, 2014

Eflite J-3 Cub Project

Made a lot of progress today! The wing is done, the tail is complete and the motor, ESC and reciever installed and programmed.

EXI 9gm servos for the ailerons, set up on their panels and ready to install.
 
Servo panels in place, control arms setup, aileron wires passed through the wing.
 

Wings joined to the center piece with epoxy, setting up.

 

Setting the CA hinges up.

 

instead of the stock CA hinges for the rudder, and the stock tail "axel" and wheel, I hand bent wire for the tail wheel using thicker gauge wire, a larger tire, and had to use large CA hinges folded over the tail axel to secure it to the fuse. The CA hinges I used for the tail wheel have a slot in the middle, and I used two laid over each other. Since the rudder will take some of the forces from the tail wheel I substituted plastic hinges for the CA ones. Installed the control horns.

 


The rudder and elevator servos, with their control wires installed, and the Spektrum AR610 reciever.
 
 

Installed the motor (a generic 480 sized motor, I think from HeadsUpRC. Recycled from some airplane I used to fly), and a 40 amp ESC, also recycled. Should be able to finish it up with the next day's work. Install the cabin windows, the engine cowl, and install the wing and its supports. I have skis for it, but put bigger wheels on it. Should be ready to maiden soon!