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This list of tips is a work in progress. If you have a useful tip that you would like to submit, please fill out this form (email for now). Credit will be given for tips used. Also check the FAQ's for more info.
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Soldering ESC leads: There's a few things to remember...
English instructions for Schulze controllers are available for download on the Schulze web site: http://www.schulze-elektronik-gmbh.com/index_uk.htm Reversing rotation on a brushless motor:
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Programming the Kontronik SMILE ESC How to dismantle a Kontronik motor: Hold the motor case in your hand and strike the end of the shaft with a rubber mallet. I could not find my mallet so I used a piece of soft lumber. Use high temperature silicone adhesive such as Loctite 587 Blue to reassemble. A small dab of the adhesive is used to keep a washer (spacer) against the bearing to prevent noise. Do not oil the bearings - it tends to wash away the original grease. The bearings are 5x13x4mm (with flange). (from Mike at Kontronik) Glue for Hacker motor: They use LOCTITE 270 on B40 motors. Others? Plettenberg 300 series motor bearings: one 11 x 5 x 5 mm and one 11 x 5 x 5 mm FLANGED bearing Plettenberg maintenance issue: there's been several instances of the cooling fan on the 300 series motors coming loose. In my case it happened with 2 out of 3 motors. The motor then runs a little hotter. Take it apart and clean the glue joint area with rubbing alcohol and glue it back in place with epoxy or black C/A |
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Problems fitting bearings to rotor head shaft (spindle) and tail rotor shaft?: I've noticed a variety of fits lately. I think that that Mikado tweaked the size of their shafts a tad larger and now the variations in production of the shaft and bearings are making themselves known. I got two such spindle shafts recently. They are different in appearance from all my other ones because they have a polished finish and the older ones are dark coloured. I measured them all just now. All the older ones are 7.93 to 7.94 mm in diameter. The new ones are both 7.99 mm and it felt like it would be challenging to force the bearings onto them. I think that the best solution is to work the shaft with some fine emery cloth to get a snug, but not impossible fit. Forcing them on or using heat could make it tough to remove or adjust them, as well as possibly damaging them. Assembling the tail pitch slider: The instructions state that if it is not threaded on correctly, it could deform the slider. If the sleeve is threaded into the seesaw earlier in the sequence, while the tail rotor shaft is available to be inserted in the sleeve, it is much easier to get it started. The shaft can be used as a sighting guide and lever, taking care that it is concentric in the end of the hole opposite to the one where the thread is started. This really helps make the threading job straight! In addition, having the shaft inside the sleeve helps minimize any deformation. Only a slight amount of filing may be required at one end, but usually not, after working the slider back and forth with some Tri-Flow oil. "The Greaser" is a nice tool for forcing new grease into a shielded bearing (while forcing the old grease out). The manufacturer, Pete's RC, has a good FAQ on bearing greasing. |
Installing bearings in blade grips: It is handy to first put the bearing on the end of the rotor head shaft and use it as a handle to guide the bearing accurately home in its seat. Balancing a LOGO rotor head: I have found that if one gets the LOGO flybar installed exactly in the middle (I use a tolerance of +/- 0.1 mm) and likewise for the distance to the paddles, there is no vibration. I have a weighted shaft for balancing on my high point (actually it's a 20 inch long round steel bar milled to 8 mm on one end, 10 mm on other). When I check the balancing of the entire head and blades, I use a level to make sure that both rotor blades line up with the head, sighting down from above against the two blade attachment bolts and along each leading edge, one blade at a time. I usually get the blades balanced separately with the blade balancer first, then do the rotor head without blades on the high point, followed by the head plus blades on the high point to double check. Any time that I have double checked in this manner, the head was in perfect balance - with or without the previously balanced main blades. So, if you can measure the distances previously mentioned with a digital caliper, I would not worry about it any further. Some more LOGO 10 assembly tips are in my review of this fine heli. Also some photos of the installed equipment are shown on a separate page. Stripped plastic hex bolts? No problem - just wick in a few drops of medium CA and let it dry for awhile. The screw will now "bite". |
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Getting the most pitch range with an 8103 transmitter: |
Gyro drifting? Be careful to have the same rudder trim setting in all flight modes. My 8103 can give numerical readings for the trims, so that I can check that the rudder trims are the same for all heading hold flight modes (hit "Select" and "CH" simultaneously). Also, the trim step can be adjusted to a smaller increment on most modern transmitters to allow fine-tuning the trim. LOGO 10 tail rotor drive gear lash: Do you have enough backlash in your gears? I'd let my tail drive gear get a little too tight. It appeared OK and I thought I could detect a tiny amount of backlash, but it wasn't enough! The first clue was that the teeth on the white main gear were getting marked from the black plastic of the tail gear - more than I had remembered. By increasing it just a tad, I gained 30 - 45 seconds flight time. Tail rotor glitching/belt tension: When I was getting some glitching with my first LOGO 20 (2000 season), I did nothing else but increase tail rotor belt tension and the glitches completely disappeared! That day, it went from 6 glitches in one flight to no glitches in 6 more flights. If all else fails... Mikado's page about eliminating interference. Schulze's installation hints. |
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Check for swashplate binding!: It is a good idea to check that the swashplate does not bind on the main shaft with extreme cyclic inputs (stick near "corner"), especially with the aluminum swashplate. A telltale sign would be rings wearing in the finish of the main shaft. You can see it happen if you remove the rotor blades, give the head a spin, move the stick, and watch for it to grab. Reduce aileron/elevator swash mix as in the above photo. Angle ball-link binding? Check the blade holders for evidence of scuffing from the bent links. One should check for such binding with the right stick near the corners while setting up the heli and this simple check might ward off disaster. The brace can be cut off to allow more clearance - many of us do that. Proper blade grip friction? Both the main and tail rotor blades should barely hold their position when the grip is held sideways to give the blade a chance to fall. |
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Batteries can kill! Recently a member of the forum had the batteries for his LOGO 10 short out in his car and burn out the back seat. The charging leads were unplugged form the charger instead of disconnecting at the connector. The result of thiis absent-minded mistake was that the banana plugs were left to brush together and start welding to quickly release the large amount of stored energy. As we discussed this on the forum, two of us mentioned near-misses where we had asked our wives to disconnect a battery from the charger. In each case our wives had done this several times before and we were comfortable in asking this of them without detailed instruction or supervision. We were both shocked to come across the banana plugs dangling near each other while still connected to the battery. We decided that a warning about how easy this can happen was in order. Do not leave bare plugs or wires attached to a battery and do not trust others to know this - it is an extreme hazard! |
Double-check your chargers settings. While we've always known to be very careful while charging our flight batteries, a recent episode shows how the new LiPo batteries are worthy of more supervision. A fellow LOGO pilot had some LiPo's go up in flames due to an improper cell count setting and there was really bad smoke - it actually caused severe rusting of metal parts in nearby helis and tools. Accidental startup. An armed ESC can suddenly start up the motor if it receives a glitch or fails. Do not plug in the flight battery until you are ready to fly. After the flight, keep onlookers away and approach the heli as if it could startup at any time and get the battery disconnected. A more casual approach will work - ALMOST all of the time:) Whatever is involved in keeping the heli from running (finger on stick, switch, radio system, ESC, etc.) CAN fail. |
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Attention BEC users: Setting up the heli on the bench? At the field? Keep a small Rx pack and switch on hand and when needed just unplug the BEC Rx lead and substitute the switch harness. It's not worth risking an unexpected motor startup. Wear glasses? You'd be surprised how wearing a glasses strap to keep them firmly placed on your face will improve visual acuity just enough to have a drastic effect on your flying. It will make a difference! Especially on a hot day when you perspire. |
Bringing more than one model to the field? I have small and large clothespins which I attach to any model that is NOT currently enabled in the Tx. I still double-check the model after I turn on the transmitter. Be careful - sad tales have been told about mix-ups! Good sunglasses are important, especially on a bright day. Besides fostering eye health, they will prevent eyestrain and make you a better flier because you can see the heli better. Hanging with glow fliers? Setup upwind. Really. |
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I made a few changes to save weight, but then swapped out some components for better ones, which added a bit of weight. The biggest single change to shave weight is to replace the receiver pack with an external BEC. I went with the UBEC because Mikado's unit was rated to only 12 cells and I did not know about their larger unit. It is tied directly to the ESC's battery lead and powers up the receiver, ESC and gyro all at the same time. In many flights, the gyro has been prevented from initializing properly (solid red light) only once. Also: Switching to the 3-D paddles saves another 20 grams, which is significant in itself. The net loss in weight was 62 grams! The current weight of my model is 2490 grams with 13 cells. Do you think that this is insignificant? I've gone from falling out of the second flip to doing 4 flips in succession (with my better battery packs). |
63g -300 mah battery and switch (as light a pack as one could have) 28g - steel spindle from LOGO 20 50g - G460T gyro/JR3121 servo 42g - stock main shaft 84g - 3 servos - JR3121 12g - 2 steel ball bolts _______ 279 grams removed |
19g - UBEC 10g - alu spindle 77g - GY401/S9253 45g - hardened main shaft 90g - 3 servos - JR3421 4g - 2 aluminum ball bolts _______ 245 grams added back |
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stock plastic (both models, no decals ) |
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LOGO 20 C/F (2 mm thick) |
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LOGO 10 C/F (1.5 mm thick) |
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One big decision with a radio is PCM or regular FM. It is a subject of endless passionate debate. You can do research online about this. In the original LOGO 20 instructions, Mikado said not to use PCM, but I had already bought mine before my kit arrived:) This recommendation has been removed with the current instructions with my new kit. The reason that they were worried about PCM is that some PCM receivers did not recover well from a fail-safe "hit". The JR PCM receiver has worked very well in that regard. It is very important to set up a helicopters fail safe settings properly if a PCM receiver is used. The motor speed must be set to near-zero so that in the event of interference, the heli goes more or less straight down, instead of holding the last throttle setting and flying off towards spectators. In the case of my Schulze speed control, I learned to set fail-safe to just above zero to avoid the long start up routine. In the beginning, I was getting a half-second glitch followed by 3-4 second slow startup which made things a lot more hairy than necessary:) Now I have it set up to go to just above zero throttle. The collective is set to slightly negative pitch and two years ago when I gained a bit of experience with fail-safe hits, the heli usually flared up from forward flight and started a gentle descent before control was restored. |
The servos that come with the PCM model would certainly be good enough for a start with the LOGO 20 - they are what I used in my first LOGO. Now I use 3 JR 9011 servos, which are smaller than standard sized servos, put out more than enough torque, have double ball bearings, and a coreless motor. The new JR9411 digital servos would also be a good choice. Considering that JR allows one to substitute better servos (at a cost of course) with a radio system purchase, you might want to try substituting 3 or 4 better servos for the 5 531's that come with the PCM set or the other servos that come with the FM set. One thing you will notice is that all heli radio sets come with 5 servos. You only need 4 because you don't have a throttle servo with an electric. I was content to keep my 5th servo for a spare. Depending on what you want to do, i.e. get a dedicated tail rotor servo or not, you will only need 3 or 4 servos with your radio set. That said, my recommendations are:
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One of the reasons that I like the JR 8103 is that it has a rotary knob that can be programmed to operate channel 7. But the big plus is a function called "monitor", which gives a graphic display of all 7 channels' operation. These horizontal "graphs" allow one to see what the results of setup and mixing are in real time as the sticks are moved. These features come with a higher price, of course. |
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It is really easy to make training gear from two 4' lengths of 1/2" dowel from the hardware store plus 4 wiffle golf balls screwed onto the ends. I enlarged one of the holes so that the dowel fits into it and screws to the opposite side of each golf ball. Notch the two dowels so that they cross exactly level, |
sandwich the joint between two 3' discs cut from 1/8" aircraft ply, epoxying the whole thing together. For added strength, I tied each leg to the ply with light wire near the edge. At the field, one can either ty-rap or use scrap copper wire to attach it to the skids. |
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In preparing for winter flying with an electric heli, a few things need to be considered:
The limiting factor in cold weather operation will be the gyro's ability to handle the cold temperature. I'm pretty sure that the Telebee gyro packed it in and caused the crash of LOGO # 1 on its 221st flight when the ambient air temperature was around -5C. I found out after the fact that -5C was its lower limit. The Futaba GY401 that I now use in both my LOGO's is rated to -10C. |
Now that I am not quite so obsessed with getting a "flying fix", I notice the cold a little more:) The Radio Glove that my wife got me for Christmas (somebody gave her a hint, hehe) has been a godsend. It is so much more relaxing to fly without pain! Because the timer isn't too easy to see through the plastic window, I've mounted a sports stopwatch to a clothespin for clipping to the transmitter antenna and I use both so that I can hear the transmitter's countdown timer and see the sports timer. I would certainly prefer not to trim a new or rebuilt model by mostly feel, but otherwise I love it! I leave the car running throughout the flight session (surprisingly little fuel consumed) and put the transmitter/glove on the dash to warm it up a bit between flights. If not for the Radio Glove, when the winds are blowing the cold would be even tougher to bear. The Radio Glove is manufactured in UTAH and they will ship from there: 801-465-4228. It is stocked in many fine hobby shops. |
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The
solution to getting more pitch (collective) without
increasing elevator/aileron (cyclic) input to the mechanics
was easy, once I understood what the CCPM mixing percentage
settings were for. I thought they should remain more or less
equal for some silly reason. Increasing the pitch % from 60%
(as the aile & elev are also set) to 80% gave me lots
more pitch range without increasing the aileron and elevator
response and causing binding of the mechanics. As you can
see from the photo of the swash mix menu screen, I have also
reduced the percentages for aileron and elevator to keep the
swashplate from binding on the mainshaft.
