Flybarless Lepton?

[owde]

I hope you didn't fracture any of your new frames, I hate it after a crash and you find a break in the frame. Have you had a chance to flog it yet. I just cut down Trex pinions if thats any help.

[prototype3a]

Generally, the usual suspects got bend or damaged. The frames survived without a scratch. I wouldn't say that I've "FLOGGED" it yet since I still haven't been able to get everything tweaked well enough to really smack it hard. I think it will be possible but just a matter of getting everything tuned right. I also managed to fix a few unrelated mechanical issues the heli had during the repair.

How do you cut their pinions down? I'm thinking about taking it to the machine shop on campus and see if they can do it for me. If not, BobOD seems like he is willing to try and do it. It may be difficult since it is hardened steel.

I suspect that this is a "trex 500" pinion but I really don't understand why anyone would need a pinion with ~3/4" tall gear portion. Seems to me that the gear portion only needs to be maybe 1/16" taller than the heli's main gear. The rest is just wasted material and weight.

I did get 2 sets of frames cut so I do have a spare set.

[prototype3a]

I took her out for a few quick test flights this evening. I got a peak of 55A and 1090w. Performance isn't quite where I would like it to be but I suspect that is because the head is only spinning at 2700rpm. The 720 feels like it is close to where it needs to be but I'm not sure what needs adjusting at this point. I'm not sure I like the EDGE blades but I haven't flown it enough yet. The control system seems to be very strong and precise after fixing a few problems and switching to Bob's ball bearing pitch links.

[prototype3a]

Stopped by a machine shop today and they cut that silly huge 22T down for me and couterbored it as well. I was amazed at how easily this was done. I guess as with most anything, if you have the skills and the right tools, anything is possible. I am extremely grateful for their assistance. I can't wait for the weather to cool off so I can go take this thing for another couple of test flights.

Interestingly, the "Hard-One" pinions are case hardened, meaning only the outer surface has been hardened. This should be a good thing as it reduces wear while staying elastic to reduce the chance of a brittle fracture.

[owde]

I just cut them down with a dremel. I wonder if you could get a machine shop to cut a front tail drive gear, I'm sure the alloy is wearing a bit on mine, when I was using the HDX 13t rear pinions they wore down real quick.

[prototype3a]

I've never had a problem with the stock hirobo tail pulley. I'm not sure I understand why they are wearing at all. What exactly about them is wearing out?

I thought about cutting it myself but I knew it would be a hack job at best without the proper tools. The shop that cut it for me, did it for free but I wouldn't want to become a burden on them or take advantage of them.

[owde]

I've got an alloy one made up by a guy in China to speed up the tail a bit, it makes the tail that bit more solid and me a bit more confident of it not blowing out. I'd love to be able to cnc my own parts.

[Helipsyko]

Short question, what is the OD of the boom?

[prototype3a]

IIRC it is 15mm (1mm smaller than the T500) I do wish it was the same size as the T500 so I could use one of the aftermarket fin clamps but that is pretty much the only reason. I've never really had any problems with my tail unit.

[fabian1675]

Hey prototype3a, thanks for sharing your info. I've recently crashed my lepton, and I thought about buying another 500 size heli rather than repairing the lepton. I realy don't see other 500 size that is laid out as nicely as the lepton. So I think repairing the lepton and upgrading it to flybarless is the way to go. Parts I need to replace to make it air worthy again. Main gear and main frame. Is the frame you have commercially available? I'd like to get one. Thanks

[prototype3a]

Well, I do have an extra set of carbon fiber frames and I think the company who cut them for me should be willing to cut more if there is interest. Keep in mind that this setup requires a longer swash antirotation pin compared to stock to make room for the I2 head. I suspect BobOD would be willing to make you one if you purchase his head.

[fabian1675]

I've used the existing lepton head and converted that to flybarless similar to what is posted earlier on this post.

[prototype3a]

I got a pretty good chance to fly the Lepton today and I think I really like it. It still has a vibration problem somewhere (according to the sk720) but seems to fly great otherwise. I still want to try a Hyperion 3026-880 though as I suspect it will run much cooler and provide a more consistent headspeed.

However, I might just be feeling happy since both my Furion 450 and the Lepton flew well today.

[prototype3a]

Since I started this journey, I've never liked the MJP CF vertical fin because they simply didn't take the time to properly measure how things fit. A result of this is that it is able to move around and the cut out for the tail shaft bearing is not cut to fit correctly. So, since I haven't been particularly busy lately I decided to finally draw up my own. If you have any design suggestions, let me know!

[prototype3a]

I was looking at my heli and realized that a true stretched fin should keep the tail blades from touching the ground. So, I tweaked it some more and stretched it out so that it is 100mm from the hub center to the bottom.

[prototype3a]

I've been flying with the Scorpion SII3020-780 and trying to locate a vibration problem. I've finally narrowed it down to the motor. It seems that Scorpion's low quality bearings allow the shaft to move radially within the bearing. So, I decided to get a Hyperion 3026-880. I've only done a few quick test flights but the sk720 vibration score dropped from a ~9, in a hover, down to less than 2. Not too surprisingly, the Hyperion's shaft does not feel loose like the Scorpion's does.

I'm hoping to give her a good flogging tomorrow afternoon.

[Mrktplayer]

prototype, sorry if I missed it but which lipo are you using? 5S or 6S?

[prototype3a]

I'm using 5s3300 TP 30C packs. 20C probably would have been a better choice since they would be lighter and provide the required power but when I was choosing batteries I decided to err on the side of more power.

[Slayaah]

I just have to share, I took over a reasonably worn Lepton from a guy who was anxious to get rid of it, traded it for Trex 250 and got money my way ..

Well it was equipped with a gaui-fly-shit-less system which were malfunctioning. Didn't even compensate cyclic at all. I replaced some worn down parts like blades (were severe damage to the tailblades and some to the main..)

I moved around the electronics a little, his installation wasn't as good as I prefer, and installed a BeastX unit. It's a home-made conversion of a stock head with a kontronik kora + Jazz speed controller and today it has SAB Fai 430mm blades and KBDD 70mm tailblades and a small raise. I can just say - it flies great! Very clean and nice.

Unfortunately I only have 4S 20-30c 3700 and 4000mah packs so it lacks some power when really pushing it but it flies very very good. Good enough that my 600s & 700 were grounded until I BeastX-converted them

[prototype3a]

What do you think of the BeastX and the KBDD blades? I have a pair in my box but I haven't tried them yet. I still have an extra pair of the CF ones that ReadyHeli used to sell and have been using them.