just flew it again yesterday with a new tail motor installed. the right yaw problem was fixed, but now i can't stop wag at 100% HH. is that sweet spot very small & i missed it or something? i went from 0 to 100% on the 3n1 in about 15 steps. not sure what gives. vibrations aren't bad & tracking is perfect. my battery died before i could even play with the 3n1 off. with the 3n1 turned off i got down to 35% HH gain & still had wag. hehe, i swear tail issues just won't leave me alone.

btw, i did install a tail motor heatsink. could the extra weight on the tail play a factor in the wag (probably)? i'm curious copperdudes & orlbuzz, what batteries you guys using these days?

yes oh my god, the tail just won't leave me alone. i think my tail motor is gone, it's just maybe it's defective or i've stalled it alittle during this timespan. i went out and flew today, at first it's ok, just not holding well enough, but at the end, the tail suddenly started feeling very 'loose', and will easily spin around during the slightest throttle change. seeing that, i did alittle analysing and i couldn't think of any other cause.

i'm using a cheapo lipo with over 200 flights, so it ain't great at all, i run 100% throttle in idle up and get only around 5min of flight time. it's a "Power" brand 1050mah 12c cont 20c burst. it ain't holding voltage at all. i also have a heatsink on the tail motor, i do get a slight amount of wag during the first 30sec maybe? it goes away i think as my lipo voltage goes down.

well, i guess i'm down until i get a new dd tail motor. urgggg... not even 30flights on this one.

Truglodite,

I have three TP 910 pro lites and the 800 e-flite.

BTW, the voltages on the new 910 were 4.10, 4.10, and 4.10 after charging on the e-flite stock charger. The voltages I gave in the earlier/other post were for a 910 with 55 flights on it.

orlbuzz

can someone post a picture?

orlbuzz, both of my tp3S910's still end up perfectly balanced (4.2V/cell). one of the packs has around 20 flights, and the other pack is much older (have to guess around 80 cycles). the older one still performs much like the new one, but usually end my flights with at least 10V on the pack. i'm also using an apache charger that i got from my lhs for $35. it rocks for getting cells fully charged (4.2V), and works for all the lipos i use (1S120 through 3S2100).

bio87, i'll post a pic or 2 of my "john adam's pro" in a couple hours. the last 7days of work have been very strenuous & i need some r&r.

btw, the tail motor i installed is "edf-50h"; it has cooling slots in the can near the endbell which is new to me. i've read "cn12-rxc" (aka "edf-50x") is the one we want. when i told this to the guy at my lhs, he swore the "h" one is the one i want for my heli & the other ones are low voltage versions that burn up quick. i don't really care if i need to replace the motors often, as long as i can do 3D with it y'know.

here's a few pics i just took of my heli (& it's excessive wiring). there is plenty of dust because it wasn't flown for over a month. it was flown twice in the past 2 days; the dust in my garage is very sticky.

i didn't have time today after work to do any further flying/gyro tuning. everything is rtf, waiting for tomorrow's short & easy day of work to end.

[edit: the heatshrinked 3n1 is nothing special. it is just part of an ex esky 4n1 that came from my (now dead) esky cp2. i had to mod the tail motor plugs so they cleared the canopy. the newer 4n1's have 90degree pins on the 3n1 side, which would've been better. there are a few minor differences between my heli & john adams' heli. john uses a tp3S730, uH swash, spektrum 6ch rx, no heatsinks, eflight 3n1, and eflight park 370 4100kV w/10T, shortened main skid struts, & he flies his phx10 in fixed heli mode. i'm using a tp3S910, eflight swash, berg 7, main & tail heatsinks, esky 3n1, himax 2015 4100kV w/8T, stock length struts, & i fly mine in governor mode. oh, and my esc isn't hardwired to the motor (hehe, no thanks). other than that, everything is identical (chopped boom, reversed grips, ...).]

sorry for the double post, but i was just looking at my pics and telling myself, "wow, john went to all extents to keep things as light as possible. maybe that's where i'm going wrong." just look at the differences i listed... most of the differences=more weight. although i can fly my pro well as is, i believe weight needs to be a higher on my priority list from now on.

so after work today i'm pulling off the heatsinks. when i have more time this weekend, i'm planning on customizing my wiring job to minimize weight too (cut all the wires to min length & reinstall connectors as needed, micro deans...). heck, i might even go for the gusto and hardwire my main to it's esc too.[8D] the hardest part for me is buying the tp3s730 packs. i already spent $$$ on some 910's, which i thought would be a good long term investment for my blade [&o]. unfortunately i don't have another plane or heli that those 910's would work well in.

Truglodite, the motor number itself is cn12-rxc, as you said. The "H" comes in when you give the number for the ducted fan unit.

See this: http://www.gws.com.tw/english/produc...stem/edf50.htm

I've also noticed when I ordered from Tower that they have TWO numbers! They can't seem to be consistent!

See this" http://www2.towerhobbies.com/cgi-bin...&I=LXHHF7&P=RF

You will also see different voltages listed depending upon the application. I don't think they are always indicative of how much voltage they will handle (Notice I said " not always" ), I think sometimes they are indicating, for example, you will get this many rps @ this voltage.

Trug, thank you for the info on the charger and the voltages. I'm looking at the Cellpro, unless I find another one I prefer under $100.

I'll add this note, I did do a dry burn in for about an hour with the last motor, and it has lasted longer than the others, I'm sure.

orlbuzz

good to hear i have the right motor for sure. i also burned it in with 2 AA batteries for 45min.

work today did not go as scheduled, so i didn't get to fly today. hopefully things work out better tomorrow.

today i had three 100% enjoyable flights!!! my first fun flights in months!!!

in fact i was having so much fun during my first flight that i was ignoring my flight time alarm. i ended up running out of juice 10' high in a turn. i had to bail it in to the street to avoid a passing car. i busted my blades & possibly a bent spindle shaft too, but oh well. i finally got my dd to stick like glue with john adam's setup so i'm happy. luckily the lhs was open, so i got some blades and took it up for 2 more perfect flights. john adams setup ROCKS!!!

fyi, i found out why i was having very bad tail wag problems. just before those 3 flights i was trying to tune the gyro again and had a light bulb moment. i realized when i was looking at my old 4n1 case to identify the proper connections on the salvaged 3n1, the cover on the 3n1 side was installed upside down. the confusion lead me to connect the 3n1 servo leads incorrectly; the 3n1 rudder input connected ch3 on the rx, and the 3n1 throttle input was connected to ch4. [sm=red_smile.gif] so reversing my connections fixed all my problems... hehe, i'm very amazed how i was even able to hover it for 3 packs like that!

btw, before today's flights i went ahead and did a few more mechanical mods. i removed both motor heatsinks and shortened the landing gear. now it looks very sporty & low profile, and without the tail heatsink the battery location changed drastically. now my heli balances with the rear of the lipo lined up with the shaft! this makes for a much less overall inertia. that tail heatsink wasn't worth blowing up my inertia. after my flights today, i'm converting to the "weight is everything" religion.

[edit: added pics with the rest of the mechanical mods done. the second pic shows the back of the 3n1, where i accidentally reversed the wires.]

back to this thread again. i wanted to mention that i found an error with the way my head was assembled, lol. after i lost cyclic authority in flight, resulting in a crash, i discovered that not only are john adams' blade grips flipped around, the rotor head is reversed as well!

if you look carefully at the location of the pitch links, my rotor head had it's ball links on the leading edge side, rather than the te like john's heli. it's a wonder it flew as well as it did, but i think i lost a pitch link in flight because of it. i rebuilt it correctly while replacing broken pitch links, blades, and the main gear/shaft.

btw, while i was buying parts for the repairs yesterday i treated myself to a new tp3s730. my collection of bladeable packs weigh in at:
1@ 3s1320 = 3.08 oz
2@ 3s910 = both at 2.39 oz
1@ 3s730 = 1.57 oz

today is supposed to have almost no wind in my area. should be fun now that my cyclic won't fail again.

-kev

you lucky you got so many batts. i'm still down right now, waiting for my lhs to have a cellpro in stock so i can get a tp910 and charge that. i dun wanna ruin my tp910 with the stock charger, just being cautious. no, everyday the sun is shining and i dun get to fly... this sux.

it's nice having batteries, but they are cutting in to my trex budget (saving for one now).

honestly, the stock charger will do just fine if you have the right node adapter for it. i've been charging all my packs through the main plug instead of the node plug using my apache charger for over a month, and haven't had a tp lipo come even close to out of balance yet. the stock charger is, if you will, more "careful" with cells than my apache. so i say go ahead and get a 910 if you need one to fly. the cellpro can wait, and the weather won't stay nice forever.

btw, i feel blessed. i flew in the calmest conditions i've ever had outside with my heli! i flew my 730 today and it was as advertised. i didn't get crazy yet, as i'm tuning and breaking in my newly rebuilt head, and feeling how the heli reacts with the john adams style head built right (lol). however i did fly hard enough to notice that i had far more lift than with the 910's and the collective seemed much "snappier"; perhaps snappy enough for tic tocs (in the right hands of course). hovers were rock solid, but i think that will change with more wind; i'm sure the 910's & 1320 would be more stable in the wind. still, i support the 730 as the best lipo when it comes to pure performance.

i cut the flight off at 8min after about 1min of tracking adjustments (9min total), and noticed that the battery felt warm for the first time! that's proof to me that the battery weight is minimized with a 730. any smaller and the battery may overheat, any larger and you just add weight.

btw, i was flying with 60%HH gain only. i'll go 100%hh + some rate% next time, but i wanted to keep variables to a minimum for this "maidenish" flight (not truly the maiden flight, but there were enough changes untested changes to make me nervous).

-kev

ya, i know what you mean, however, the grade 9 end-of-the-year projects are killing me, i have like 3 of them due at the same day, and 3 presenations one following another. these projects are worth 30% of our total mark!!! so i dun think i'll be doing anything but these this week.

my lhs might not have a tp730, if non of my lhs's dun, i might just get a 910, i'm sure it'll do fine for me. i'm no where near banging it adn can do with a little longer flight times for learnign inverted ff. i wonder if the adapter for the cpp charger is the same as for the cellpro for a tp batt? the cpp's been giving me problems lately with the tail, i've heard that a better speed control will fix it, i dun know, i'm thinking it's the batt, so if i got the batt and the tail still ain't fixed, i'll probably return the batt after about 1 use and get a trex SEV2 (otherwise my lhs might now let me return my batt). if it fixed the tail issue, i might stay with the cpp for a while longer. so the cellpro will be my last step for getting a trex before getting the kit itself. i already have 3xhs65 mg and a fut pcm reciever and a fut 7chp. so all i need if i got the cellpro is a kit and gy401 w/s9650. i really hope a new batt will solve my tail problem though. still have to wait and see.

I want to ask this question. Has anyone tried shortening their boom as Mr Adam's did? The article say's this will allow improved CG and a polar amount of inertia to the main shaft for quicker 3D response.

I shortened the boom as described in that article when I installed my DD tail. I don't know about quicker 3D response, but it makes it easier to balance the heli correctly. Without shortening the boom I would have to shove the battery as far forward as possible into the canopy, with it shortened I could just keep the battery where I always put it. It stands to reason though that it would give you quicker tail response.

csrc makes one that is cheap
http://www.commonsenserc.com/product...products_id=85

double check the polarity though, because they are in a change over that is changing the polarity of their packs.



About the tail boom, up to 10.5 inches from the frame is as short as you want to go. I dunno that it would add too much to 3d flying, because it actually decreases leverage, but it brings the weight in closer to the heli for better repsonse time. They are probably pretty close to cancling each other out. I would agree with what ajenkins said though.

it is somewhat hard to prove if the shorter boom improves tail response. it's more complicated to calculate than considering the inertia and torque of the tail alone. what matters is if the overall effect of reducing inertia is more or less than linear:

tail response = alpha = (T - F*r)/I

T and F are fixed, and r is just the normal distance between the tail motor and main shaft. seems simple, but it's not that easy because:

I = m1*r^2 + m2*r2^2 + m3*r3^2 +..... for every part of the heli.

we'd have to measure the overall inertia of the heli first, which isn't that easy to do. if you could do that accurately, it would be fairly easy to mathematically prove one way or the other if tail response is better with a 10.5" long boom. i think i'll just take john's experience with the heli as proof, rather than rig up some mcgyver style lazy suzan with ropes pulleys and weights and do a bunch of math. the poor guy has probably a million dollars worth of brand new rc products paid for by horizon, with which he can do all the frankenstein experiments he dreams of. imagine getting paid to experiment on dx7's, cpp's, brushless stuff, lipos... poor john. hehe, j/k. i'm sure he's earned it.

here's the equation if you want to prove something one way or the other about john's gyro location, it's actually simple to prove:

inertia of battery and gyro in position A = mbA* rbA^2 + mgA * rgA^2
" " " " " " in position B = mbB * rbB^2 + mgB * rgB^2

where mB = mass of battery, rg = radius of gyro, and .... you get the idea.

good night,
-kev

True, I shouldn't have implied that it goes without saying that it would be faster. In plain English, we have several forces which can conflict with each other. On the one hand, there's the fact that if the tail boom is longer, the tail motor has to travel farther in order to rotate the heli a certain number of degrees. On the other hand, there's the fact that the longer the tail boom, the more leverage the tail motor has to overcome the inertia and start or stop the heli rotating. We'd need to work out the correct coefficients for these variables to solve the equation.