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Posted by Zoandar | Oct 31, 2008 @ 10:40 PM | 3,506 Views
This is a copy of one of my posts a while back on the Lama V4 thread, detailing what I learned about the initial setting up of my Lama V4 4-in-1 unit:

If you are sure everything is aligned and the setscrews are holding, I can tell you how to get rid of the yaw completely. It involves moving the proportional setscrew WITH the Lipo connected ( which you are told NOT to do). When you do that, it slides the entire proportional adjustment "range" either toward CW or CCW. But to get that, you must turn the screw the OPPOSITE of what you might assume would be right.

So if you need more CW adjustment for the prop. screw, turn it to the LEFT a bit while the Lipo is connected. Then you have to unhook the Lipo to make the proportional adjustment by turning the same screw to the RIGHT to reduce CCW yaw.

No matter how badly the Lama yaws in either direction, I believe it can be completely removed by following this procedure, because I did it on mine with the stock motors to correct CCW yaw that seemed to be "not able to be adjusted out", and then again to remove CW yaw when I got my SE180s.

Find the middle of the range of screw travel in both the gain and prop. screws and set them there. Then work the propr screw with the SMALLEST possible increments you can manage. It takes time, but you will succeed. I watched my yaw rate drop from 1 revolution per 10 seconds down to where it took over 100 seconds to make one revolution of the tail, at which point the TX trim...Continue Reading
Posted by Zoandar | Aug 01, 2008 @ 10:32 PM | 3,560 Views
Early in my hovering practice on my new HBFP, I had a rather nasty crash into the blacktop of our road. It caused a crack in the main frame that went undetected for a few more flights, but eventually the frame broke in 2, just at the front of the main shaft support tower.

During those early flights, I had not yet been using the canopy, as I would periodically tweak and adjust things to improve my ability to hover. I replaced the frame with a new one, and continued on. But due to the lack of canopy, I had noticed that the thin tab that Esky provides as a 4-in-1 mounting shelf was allowing the 4-in-1 unit to actually "dribble" up and down whenever I got any kind of head vibration. As a new flyer, I hadn't yet figured out all the ways to correct vibration, so as long as the FP would fly, I kept at it, vibrations and all. But I had to think that the rate gyro in there could be a lot happier if it wasn't bobbing up and down.

I got to looking at the way the 4-in-1 was sitting there, and looking at the piece of frame that had broken off, now that I had removed all the heli parts from it. Why not use it to make a more sturdy mount for the 4-in-1? I had done something similar with a piece of aluminum angle on my Lama V4, and it's 4-in-1 was no longer bobbing around, so I could do something similar here. But instead of using more aluminum angle, I had the perfect fitting piece in my hand. Just snip off the OEM 4-in-1 tab from the broken frame piece, invert it, and it...Continue Reading
Posted by Zoandar | Jun 14, 2008 @ 11:37 PM | 3,680 Views
I have been learning to hover my new HBFP. The stock tail motor died on me VERY quickly, so with the help of Blade-Killer's advice, I did a Direct Drive (DD) tail motor modification. It works very well, and I am back at learning to hover again.

Since the tail motor gave up so quickly, I added a main motor for the FP to a recent parts order. I decided to "run-in" the spare FP main motor so that, when I need to install it, I won't have to spend the time running it in.

Instead of using a AA battery, I decided to use a Regulated DC Power supply I have for electronics hobby use. It was a good thing I did that, otherwise I would never have seen what happened during the break-in of the motor.

I started feeding the motor 2V, and added some Trinity Commutator Break-in drops, and olied the bearings. My power supply has a built-in ammeter, and the motor was pulling between 200-400 mA.

After it ran for a few minutes, I stopped the motor and flushed the bearings and commutator with plastic-safe contact cleaner, blew that out with compressed air, re-oiled the bearings, added a couple more drops of Trinity, and powered the motor back up. When the total run time approached half an hour, the motor started to twitch a little. I had it lying on a piece of terrycloth just so it wouldn't move. I started watching it to see if the twitch was being caused by anything obvious.

Suddenly, the speed dropped, and the current draw shot up to 900-1000 mA. I shut it down and inspected...Continue Reading
Posted by Zoandar | May 20, 2008 @ 07:15 PM | 3,507 Views
I finally got a decent evening with very little breeze. So I took the Lama out for a spin. Learning to fly with a "headwind" is an interesting switch from indoor flight, but it was soon clear that when heading into the westerly breeze, I wanted as much forward stick as I could muster. I had also recently learned in my garage that adding some throttle trim gives you much more sensitive elevator response on the heli. Outside, I pushed it all the way up, along with the forward stick trim.

I could manage slow headway into the west, and then found that tacking on a zig-zag course helps keep the FF speed up. Turning and crossing the wind, or flying east with it, the little Lama goes like a rocket!

I managed to fly out 3 Lipo packs, and hated to come in. But I think the Lama deserved a nice rest after flying so well. I did dump it a few times, but with all the upgrades it came out of each tumble damage-free.

On the 3rd pack, the breeze did pick up a bit, and started to make flying west impossible, so I landed (gracefully! ) and then picked up and moved around to the lee side of my house. There, I was able to fly out the rest of the pack with no problem.

I am still using training gear. Every time I get brave and think I'll remove it, the gear "saves" me from some crash, so I figure no hurry to lose that advantage. I just cut the grass today, and we keep it pretty short. But the balls on those training gear like to "snag" the grass when lifting...Continue Reading
Posted by Zoandar | May 14, 2008 @ 04:36 PM | 3,668 Views
I installed the "complete" aluminum (AL) upgrade kit from KA-Planes, where you get everything for $49. So I have the aluminum blade holders as well as the swash plate, etc.

There is a disadvantage to those AL blade holders. Their threads don't "lock" like the plastic ones, so they ship nuts with the kit to help lock them. I much prefer nylon-locked hardware over using 2 threaded devices that have to be tweaked several times to get just the "right" tension when locking them together. So I came up with an idea.

I can use CA or epoxy glue to fasten nylon nuts, or self-made threaded nylon 'discs' to the bottoms of each blade holder, andd do away with the lock-nut requirement.

As near as I can tell, these blade mounting socket-head cap screws seem to be #2-56 thread. If anyone can verify that for sure, I would appreciate hearing from you. I don't have that size tap or nylon nuts, so I need to do a bit of online shopping first.
Posted by Zoandar | May 13, 2008 @ 11:12 AM | 3,501 Views
I spent a couple hours last evening trying to work out a strange incarnation of the much-discussed Toilet Bowl Effect (TBE), in which the heli will maintain a heading with it's nose, but swing around in a circle as if suspended by a string, and looking like it is being flushed down the drain. The Lama would lift off and then hover nicely, but as soon as I put in any cyclical input, it would start to pick up some TBE, eventually in a large 4 foot diameter clockwise circle.

I tried all the usual tricks that normally fix this:

- making sure the flybar was not bent, and moving easily in the rotor head

- Setting all the blade grip screws to the same tension (I prefer to keep them snug enough that the blades don't fold in when you land the Lama and shut it down, but still loose enough that a fingertip can move them by tapping on them).

- Checking for bent inner and outer shafts

- checking for binding anywhere or gears missing teeth

- I even re-adjusted the 4-in-1 to get out the bit of clockwise yaw I had picked up after installing the aluminum upgrades. I thought that might help.

- Finally, in despearation, I loosened up the blades so they swung freely.

None of this had any affect on the problem.

Before going totally nutz the next day, I decided to try moving the test flight from my living room out to the garage. The Lama lifted off, hovered very nicely, and flew around well.....all with no sign of that 4 foot TBE circle.

I took the Lama down to my basement, where I
...Continue Reading
Posted by Zoandar | May 10, 2008 @ 10:55 PM | 3,954 Views
I have been noticing that the aluminum angle and more-forward-mounted 4-in-1 on the very thin mounting shelf have caused it to droop forward and put the 4-in-1 on an angle after a few flights. Presuming the internal gyro would work better if it were kept as level as possible with respect to the the heli, I have drilled a small hole in the upper port side of the firewall, and fastened a length of insulated solid copper hookup wire there. The other end stretches to the unused round hole in a tab atop the port side servo unit. I used this wire to hold the aluminum angle up in a level position.
Posted by Zoandar | May 09, 2008 @ 09:34 PM | 4,998 Views
Upgrading the Lama V4 RC helicopter to Extreme First Edition (FE) 180 Ball Bearing motors has presented a heat problem when flying with the stock canopy on, and a Vigilante Tail Boom in place of the enclosed stock fuselage tail.

These motors run HOT. Even after a 3 hour break-in run on a AA battery, they will reach 114F when flying with NO canopy. Add the canopy, and the front motor hits 142F, the rear 130F.

At those front motor temperatures, the 4-in-1 starts to fail and sporadic drop-outs of the motors occurs, as well as a rare but occasional servo glitch. So I decided to try and deal with the issue of the tight confines E-Sky built into the 4-in-1 and motor placement.

Here is the stock configuration after installing the Extreme FE 180 motors and heat sinks:

See attached "Lama V4 with first-edition Extreme 180 BB motors" at the bottom of the Blog.

Note that the front heat sink isn't visible behind the wires, but it is just as close to the 4-in-1 as the rear sink is to the tail boom mount. So the 4-in-1 is exposed to the high heat thrown off by the front motor.

Install the canopy, and it can be seen below that most of the airflow available from the rotor swash gets cut off by the top of the canopy, creating an oven inside it.

I have outlined the approximate location of the front motor.

See attached " Canopy mounted showing front motor location"

The first step I took was to mount an aluminum 1.5 x 1.5 x 1 inch angle on the small ...Continue Reading