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backburner1955
06-16-2010, 11:38 PM
Here's a way to do it with a laser (http://www.rcgroups.com/forums/showthread.php?t=893687). I haven't tried it myself yet, I just use the hover method. I suppose if you set your pitch curve to a flat 0* you may not even have to strap it down given enough floor space.

This is Great...

http://i263.photobucket.com/albums/ii128/EQMOD/sub/lvl6.jpg


I think I will try to use a "Laser" to track my blades too!!

http://img.photobucket.com/albums/v330/Insomnomaniac/dr_evil_laser.jpg

Stenz28
06-16-2010, 11:54 PM
If you need to have some pitch to correctly set the tracking, why not use negative pitch? It's what I do and don't have to try to hold the heli down with anything. Spool up wherever (my living room) while kneeling on the floor 15' away; switch to idle up; go about 70% throttle and -5% pitch; lay down and check tracking.

And as for straping the heli down... The landing skids and frame attachments are not generally built to hold the helicopter's weight in an upward direction. The rotor is what the heli hangs from and what supports all the heli's movements. Going full + pitch could very well tear the skids from the frame. (this makes me think of that vid of the guy who left the jesus bolt off... Wheeeeeee!)

I think...

:)

SightSeeker
06-17-2010, 08:09 AM
I see you have an upgraded motor on there. You don't have the head speed to hight for the blades do you?

Also I don't know if it's just me but when I use the pitch gauge to 0 out center I always have perfect tracking every time and I've crashed and pitched more than I can remember.

Dusty1000
06-17-2010, 11:25 AM
I usually track my blades with the heli on the floor, collective at mid-stick - which is 80% throttle for me. I can't think why load would have to be applied, since the purpose of tracking is to make sure both blades are at exactly the same pitch. If they track at 0 degrees, they should track at 5 degrees or whatever, and vice versa.

Dusty

Cailid
06-17-2010, 12:21 PM
I usually track my blades with the heli on the floor, collective at mid-stick - which is 80% throttle for me. I can't think why load would have to be applied, since the purpose of tracking is to make sure both blades are at exactly the same pitch. If they track at 0 degrees, they should track at 5 degrees or whatever, and vice versa.

Dusty

The main reason that I can think of for having a load on the blades when adjusting tracking is that there's flex in the blades and some slop in the head. So with no load the blades could be slightly up or down, or just sitting in the middle. But with a load the blades will always be forced to the top of their movement range and held there while adjusting the tracking. When doing normal flying the blades have a load on them and will be in the same condition as when the tracking was set.
I don't know just how much difference this would make in flying, but I can see it making some. It may not make enough difference to be noticable but since you're adjusting the tracking anyways, why not do it with a load on the blades.

Dusty1000
06-17-2010, 01:05 PM
The main reason that I can think of for having a load on the blades when adjusting tracking is that there's flex in the blades and some slop in the head. So with no load the blades could be slightly up or down, or just sitting in the middle.

Slop and flex should be exactly the same for each blade though, and even if it wasn't, it's the blades whizzing through the air at either the same or different pitches that determines whether they track or not - as far as I know. :thinking So that pitch might as well be zero.

I find tracking at mid-stick to be very accurate, at least partly because the blades are flat so it's easy to see if they are out by even a tiny amount, due to the much thinner profile of a flat blade compared to a blade at say 5 degrees pitch.

Tracking shouldn't be any different at any point throughout the collective range than it is at mid-stick - and if the blades did track at say 5 degrees pitch, but not at 0, then something other than tracking needs adjusted/fixed.

Dusty

1BADAIR
06-17-2010, 01:10 PM
i use a flybar lock and good blades. rarely have to adjust tracking after a rebuild.


if i do have to adjust it i check while hovering
if you changed the motor , esc or pinion your HS was probably too high

Sky1trek
06-17-2010, 02:08 PM
I remember in 2008 tracking during a hover with the heli 10 feet away. I knew it was getting closer by the sound. It's true, you loose focus. When I switched to the body of the heli it was more like 5 feet away. That was very unsettling. Ever since then I do it at least 20 feet away and adjust the best I can. As too holding it, wouldn't even consider it. Basic geometry, you've just increased your exposure from 1/2 degree at 20 feet to like 60 degrees not to mention next to no dissipation of energy. I think we all need to be aware of the probability of structural failure. When you factor in something missed in a repair, a part built on Friday or a part that just fails, the heli deserves a little cautious respect.

Cailid
06-17-2010, 02:17 PM
The latest in blade tracking safety gear. :)





http://www.bulletproofme.com/Images/Bomb%20Suit%20EOD.jpg

Dusty1000
06-17-2010, 03:45 PM
Lol, I've thought about wearing a full face bike helmet with visor down to track blades, but so far I have never bothered. What I do is power up slightly above mid-stick first, hoping that if it does blow up, that's when it'll happen. Then I go back down to mid-stick and peer at the blades from round the side of the sofa or kitchen cabinet or something.

A good tip I once heard, to avoid having to look directly at the blades at all, is to use a mirror. Maybe not as good as the laser method, but it's something more of us are likely to already own :)

Dusty

supersport
06-17-2010, 09:26 PM
Being back 15 feet didnt work for my last year.

I had a trex tail blade grip break loose and I was standing behind it 15-20 ft. The ball on the grip hit my forehead almost dead center. The ball dug into my head, and the force of the hit was enough to knock me down on my butt.

The new bolt had sheered causing the failure.

But I do not and no one else around my heli stands behind it any more. Had that been a split sec off to the left or right I am sure I would have lost an eye. Took me two weeks to get rid of the bump and longer for the cut to heal.

So even if your just learning. Its dangrous to stand behind the heli even at 15-20 feet. :shock: