HDX (Lepton) 500

Once upon a time HeliDirect I am told, sold a version of the Hirobo Lepton 500, called the HDX. I know I have one, but I don't know the real history, as it has gone legacy. I bought this used, and believe it is an HDX 3D-500SE, as that is what I was told when I bought it back in 2011. I am trying to get a manual from HeliDirect. It was in great condition, I did crack and replace the frames with a much sturdier version several years ago when I could get parts for it from HeliDirect. This is an amazing little heli. It uses a push--pull system that is very busy, allowing it to use micro servos instead of standards on a 500 sized heli. It has run wonderfully but for having developed a seizure disorder that has plagued me and kept me from flying her for the past few years, which I think I solved today! She would be fine and then all of the sudden her controls would "seize up" and release. In flight this never amounted to more than a "WTF?" and she would return to normal before any badness happened.

As I was tuning up her CCPM cage today, she did it a few times and I was actually able to see what happens. I don't know why I never noticed this before, it's not the first time she has done it on the ground. What I noticed in two separate events that the reciever blacked out, came back, but didn't show a drop: steady reciever light. Now in chasing this problem I have replaced everything electric, not sure about the ESC and its piggy-backed separate UBEC, which is key. I even tried grounding the boom and its Van de Graff static to the frame, and oiling the belt. When I saw this it occurred to me this was a power problem. Is the UBEC bad? 

I removed the separate UBEC circuit and resoldered the wires from the ESC (when you use an external BEC instead of the one built in on the ESC, you should/need to cut the red wire from the ESC to isolate its BEC, so I had to re-establish the red wire). The BEC on this ESC is not a linear BEC, but UBEC, with plenty of amps, so I really could have used it, so, I am. Since completing this repair, the problem is gone! Huh. We'll see tomorrow when I take her up. I'm pretty excited.

HDX 500SE with the stronger frames. 

Look at that complex set of levers! Pitch and Elevator servos.

Rebalacing... 

Perfect as is!

That's the one 4S battery I have left. I used to fly her 4S as that is the biggest battery that will fit. I plan now to series two 3S batteries for 6S voltage. (Um... that isn't actually going to work now that I think about it. They are only 2200 mAh, so they would be way to short of flights).

Curiously the CCPM wasn't quite square, the swash plate was a bit high. Did my technical standards go up? Well... One issue I can't fix is the swash pitch. She is all square now, everything's 90 deg on the cage. The most up pitch I can get is 10ish deg because the mechanism tops out, but there is plenty of room for neg pitch to almost 15 deg. How little was I getting before I lowered the swash to square it? Is this why I had her a bit unsquared? This should be fine for sport flying but I may need to bring the swashplate down more to get a more even pitch range with more up pitch.

Very nice!

I don't think I ever had the OEM canopy (is the one she came with original?), so she has this one now. I want to change it to read HDX instead of Trex. I think the tail boom is also a replacement.

No matter what she is one very nice machine!

UPDATE (6/8/20): So... HeliDirect has no manual, and no parts. I can use a lot of Trex parts, but what if I strip the main or autorotation gear? I think that is really the only parts that are specific to it, that I can't replace. What do I do, not fly it????

Heli up, heli down, heli up!

I brushed off the Align Trex 600 EFL Pro, and programmed it into the iX12, an easy process on an FBL system that is already set up and programmed, as is the case with this heli's Spektrum AR7200BX (since discontinued, an AR 7200 receiver with a BeastX FBL system). Create the model in the transmitter, make a reversal here and there, the usual model programming and she was all ready.

I fly her 10 to 12S, Sport. So much tech!

Once I set her up took her out and flew her, tuned the tracking one turn, perfect. She flies wonderfully. I was pretty nervous, and brought her nose in to land. She came down sweetly but the tail landed first and the tail blades caught in clumped grass. The tail blades delaminated and the front torque tube gears stripped. One tooth on the auto-rotation gear split. There is no other damage. Pictured above is after I removed the tail assembly, so it does look like devastation! I have to replace the front toque tube gears set, the auto-rotation gear, and the tail blades. Since this is one of my two pure Align helis I searched for all Align parts. Medusa Heli on eBay had everything I needed, ordered and parts are in their way, $50 later!

UPDATE:  Turns out I have the Front Torque Tube gear set for a 600 heli, so I went and installed that. Now waiting on the replacement auto-rotation gear and the new blades.

I turned my attention to the Align Trex 600e PRO with its beautiful flybar cage! Programmed it into the iX12, and reset up the entire cage from servo control arms to the blades, all 90-square now! I increased the pitch from 11ish to 13ish, and aileron/elevator to about 7.5ish.  Oiled the bearings, re-balanced the blades and ran her up on the bench at low speed to make sure everything stays put and runs balanced and smooth, sans main blades.

Bench run up.

Heli day in the lab.

Align Trex 600e Pro, Quark gyro, Castle 80A ESC, Align servos all around, Spektrum AR8000 receiver. Very nice machine.

All the electronics and wires tucked in.

Ready to fly! My favorite size of heli, the 600.

Heli magic, Pulse XT60 Noise

Gnarly skies, but no wind to speak of!

Brought out the HK500 FBL and flew two wondrous packs! 

She flew wonderfully. I gained confidence and felt in control. A couple of errors were quickly recovered from, flew nose in and landed, took off again, never out of control. I really enjoyed it! Was ready to fly some more, but some others showed up and I don't really feel comfortable with others watching. I am going to get the other helis set up on the iX12 and focused on flying them,  and more sim time!

The Pulse started fine, but for a couple of times would slow and quit at WOT after a minute. This stopped. On the ground she is pretty smooth, a little 4-cycling. Up in the air she flies well, but gets really noisy with sputtering and the occasional backfire at WOT. I don't know why this happens. It's weird, but she otherwise works great. I have taken to flying 40:1 because of the oil spitting, mostly in the 10cc's. I don't think it will make a diff, but I am going back to 30:1. I thought it might be rich, but the needle is cleaned out as much as is good, and I read 4-cycling isn't from being rich, and that a little is normal. I don't know how to fix it. I worry only because I don't want the engine to be damaged, especially the occasional backfire pops which scare me. Have to wait to test it.

Oh, this pic. Not a crash. Landed fine, taxing in, made a turn, and all the sudden she dropped on her knees. The hardpoint delaminated, and just came off. 

It was in one solid piece, it didn't break. No damage to the plane. The front tabs were stuck in the fuse, the back one's came out clean. 30 min epoxy, tapped into place snug, then clamped.

For good measure I counter-sunk a couple screws forward, one aft. 

Should be good and sound! 

Sbach Evolution 10cc running and flyable

The Evolution 10cc on the Sbach has been a challenge. Recent over haul damaged an O-ring on the low needle which has two of them, none to be found anywhere, but Horizon Hobby found a carb set and sent them to me! I replaced the damaged O-ring, and set about tuning the needles. Idle is best achievable, pretty much at stock settings, Low 4-1/4 and Hi at 2 (stock 2-1/4).

Idles good, nice acceleration, good high RPM. The pull back to idle is slow. This usually indicates a rich Hi needle, but leaning it doesn't improve it. 

She still spits a LOT of oil... at 40:1.

Looking forward to taking her to the field so it can go wonky again. I'll put the cowl on guaranteeing it will.

I like the look of wheel pants, but at grass fields they take a beating. I have 3 planes with them still. I removed  repaired, repainted and reinstalled the Sbachs pants.

HK500 FBL is ready!

Got the HK500 FBL programmed into the iX12, made a few adjustments and took her out for  hover test. Ready to go! Time to head out and crash her!

Stik long running aileron spasm problem solved!

I have written a couple of times about my long running issue with the ailerons on the Stik going rogue and spasming at WOT. They would move like crazy and sometimes lock up in a hard roll. A few weeks back an intense uncommanded high speed snap roll resulted. Last time I took her out to the field she did it, and I grounded her. 

I had read on an RC crash site on Facebook that a plane had uncommanded aileron roll to the site of the crash that was fixed by balancing the prop and padding the receiver against vibration. Since I have tried everything, changing leads, torrid, changed servos, changed the ignition, and eventually the receiver. Nothing worked, so I decided to try the balance and protect. The prop did need balancing, and I padded the receiver with a gel pad and foam around the receiver. Today I took her out:

Problem solved! Wow... 

Working out the bugs

And there have been bugs...

Having gotten the settings on the RCGF-USA 26cc where they seem to want to be, she still runs a bit 4-cycling at WOT, but there is power aplenty and she runs o/w smooth, with a reliable and usable idle. Since I am going to check the balance on the Stik's prop I went ahead and checked this one, and lo, she needed some balancing. I suspect the painted tips have worn a bit. Not sure what difference is made, but I do think it is important.

As illustrated, possibly, here. I had read in an FB post about a plane lost due to vibrations in an unbalanced prop creating a signal that caused an un-commanded fixed roll to the site of the crash. I have had this problem with the Stik where at WOT her ailerons would become possessed and endure paroxysms of movement, then locking in a hard roll, and once in flight one helluva snap roll had resulted. It only happens at WOT. I have put torrids on everything, changed the ignition, changed the servos, changed the servo leads from the receiver, and recently changed the receiver, but the problem remains. Having read this, I balanced the prop, and she did need a couple of micrograms of balancing. The prop is clean and properly balanced. Next time I take her out I will let you know how this works out.

They also mentioned heavily padding the receiver from vibrations, so I took my last piece of gel padding (I used to use this on heli gyros, not sure it helped), and placed it between the fuse and the receiver.

Suspended there.

Surrounded by a foam cover-all. This is about as isolated from vibration as I am going to be able to make it. All I need now is some cooperative weather.