loopzilla
Posts: 36
Joined: 2/21/2004
From: Indian Harbour Beach, FL, USA
Status: offline
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The following is a copy of my post on RC Groups:
Hi,
I ordered my Aerohawk from RCMart back on February 21st, and I finally recieved it Saturday. During that wait, I read up on all the threads I could, and flew the FMS Aerohawk simulator with a game controller incessantly.
I have to tell you, the Aerohawk IS VERY UNLIKELY to fly right out of the box! I tried for all of about 3 minutes before I started learning how things should move, and that they weren't!
First, the head was sticking so badly, no amount of servo or centrifugal force would make them track straight. The bearings in there are what led me to believe it should move freely. So, I took it all apart and started finding out why it was so stiff.
The head needed sanding down (part 25 on the assembly diagram). I sanded it until, when it was snapped into part 29, there was light visible all around. I took quite a bit of material off with 400 grit paper.
Then, I noticed the ball joints had material left from the mold, and sanded them round with 220 grit.
The flybar was sticking in the head, so I bored out the hole in the head just slightly with a drill, and sanded any imperfections out of the actual flybar (part 33) until it rotated freely.
The main motor to main gear mesh was awful, and I corrected it. As well, I moved the servo linkage back to the second hole in on the servo horn (inward one hole from the outermost) so I wouldn't over correct.
After all that, I was hovering - albeit without much control. So, I benched it and started looking at the main gear alignment. I cut off that silly tubing and put on a CNC shaft collar. While I had it all apart, I put in a swash ball. The linkage didn't look right with the servos at home position. The swash wasn't in the correct alignment. I put on adjustable linkages, powered it up, got it level, and tightened them down.
It hovered perfectly, as long as I didn't touch the controls and got out of GE (ground effect). No trim necessary.
It could stand a little more power, hover at 75% throttle, so I dropped in a Johnson motor with the stock 10T pinion! WOW! Noticeable difference, but not crazy. Hover at 50% throttle.
I flew it for about 10 batteries, then decided to try my EDF-40 ducted fan, with MJP finset. What a mistake. I cut my tail boom down to get better center of gravity, without moving my battery so far forward that it would fall out.
The fins were a waste, as they position the fan so off center, you can't correct for it. So, I drilled the fan itself and slid it onto the boom. Well, with no amount of CA would it keep from spinning around the boom in flight. So, I took a couple of pieces of CF rod and created braces.
Well, after cutting 2 inches off the boom, the fan doesn't have as much leverage, and performs very erratically, even with the bracing. I think the fan will work, but I need more flight time first.
Direct drive seems to be the way to go, or I guess I could increase the gain on my Gyro - something I don't want to get into right now.
I ordered a set of Yukohono's blades (can't wait, cause these stock blades cone so bad it is silly), a direct drive kit (gonna try 3x2 and 3x3), and a new tail boom.
All that said, what a great weekend. The fun is in making it work, and trying new things. I only broke one part in all of that, a flybar, learning in my (10x10) kitchen. This thing is MAD durable.
Definite mods:
swash ball
shaft collar
direct drive tail rotor (I think)
adjustable servo linkage
Things I suggest in a spare parts kit:
blades
flybar
skids
swashplate
head
tail boom
all control links
So, for all you disbelievers out there, this thing does work and flys well so far. No CNC swashplate or $100 parts necessary.
I recorded almost all my initial flights on video, if you want to see I'll post it.
Later,
LoopZilla
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Printable Version
All Forums >> RC Helicopters >> Electric RC Helis >> RE: Aerohawk, Can't figure this thing out! Help!!! 
RE: Aerohawk, Can't figure this thing out! Help!!! - 
, separate is the best deal.. and a good gyro.. since the pcb board really suck..
