450 Pitch problem

[Harford]

I am setting up my Trex 450 after upgrading the BeastX firmware to V5.2.2.
I have a problem achieving zero pitch at mid stick. With the blades positioned diagonally to the longitudinal axis, I have 0 degrees, with one reading and negative 2.3 degrees when I rotate the blade 180 degrees. I have the same result with both blades. I am not sure how to adjust this.

The swashplate is level. Any help would be much appreciated.

Many thanks
Michael

 

[D.O.G.]

Hey Hartford. My self, that's where I adjust the link on the FBL or DFC head. If the surface your Heli is on, is level and the swash is level too. Plus the servos are @ 90 degrees @ mid stick. That's when I adjust my link on the head to get close to zero then. That's just me .

 

[Harford]

Thanks D.O.G. First of all. the surface I was working on was not level. I fixed this, but I still have the issue. One pitch reading is 0.2, rotate 180 degrees it is 1.9. If I adjust the link, my concern is the current reading of 0.2 (which I think is fine) will change. Guess I have to try and see what happens.

 

[D.O.G.]

You'll never get it perfect. Get at close as you can to zero and be done with it. If you start over thinking it...you'll never fly Lol. Good luck and don't forget

 

[Harford]

Understand. Just about to take the head off and check that the swashplate really is level. This will be my third time...

 

[D.O.G.]

3RD time is a charm or in our case, a pain in the butt

 

[Harford]

It was fine, just like the last time I check.ed.

 

[D.O.G.]

That's a good thing then. A lot of induvial do a wonderful job leveling their set up but forget to level there surface that the Heli is on first

 

[Harford]

Overlooking the basics, like others, I am guilty ..

 

[Geena]

I am setting up my Trex 450 after upgrading the BeastX firmware to V5.2.2.
I have a problem achieving zero pitch at mid stick. With the blades positioned diagonally to the longitudinal axis, I have 0 degrees, with one reading and negative 2.3 degrees when I rotate the blade 180 degrees. I have the same result with both blades. I am not sure how to adjust this.

The swashplate is level. Any help would be much appreciated.

Many thanks
Michael

"I have 0 degrees, with one reading and negative 2.3 degrees when I rotate the blade 180 degrees" Asssuming you are using a digital pitch gauge? Are you leaving the pitch gauge on the blade when you rotate it 180 degrees? If you are, that`s the reason for the different readings. You zeroed the gauge while it was facing lets say..the nose of the helicopter, and then when you rotate the head....the gauge is now facing the opposite direction, and is now out of zero. You have to take the pitch gauge off of the blade rotate the head, and put the gauge on the second blade...so that the gauge remains zeroed. Hope this is helpful.

 

[Harford]

That is extremely helpful. I have been suffering from the misapprehension that when rotating the blade 360 degrees, in an ideal world the pitch reading should consistently read 0 degrees (or close to it). Thank you very much for enlightening me. I have been using a digital pitch gauge.

 

[Geena]

Another thing to watch out for, is not to move the helicopter when you put the gauge on or remove it from the blades. If you move it, you need to re-zero the gauge. When I`m setting up a small helicopter, I like to use small sandbags to help hold it still while I work.

 

[Harford]

Much appreciate the advice. Thank you

 

[Harford]

Well I flew the heli today and it performed very well. Can't say the same for the pilot

 

[Marcello]

You adjust the linkage to the blade grip arm of the blade that is off -2.3 until you get close to zero pitch. This won't affect the other blade that's already zero pitch.

 

[Harford]

Thank you for this advice. The issue was that it was the same blade, showing 0 degrees in one position and when rotated 180 degrees showed -2.3 degrees.

After taking Geena's advice I have measured the pitch multiple times in multiple positions, using an Align digital gauge, removing the gauge and zeroing after each reading. I have never achieved a consistent result. I convinced myself that the swashplate must not be level, went through the process of setting it up again - it was out but not by much. After all this, the results were as follows, measuring the same blade at 90 degree points, following the procedure outlined above :
Blade One : 0.5. 0.9, 0.8, 0.7
Blade Two : 0.6, 0.7, 1.1, 1.1
I then moved the pitch stick to full positive, full negative and back to mid point. Took the last two measurements again which were the 0.8 and 0.4.

Having not achieved a perfect result, and not wanting to succumb to the old adage 'a poor workman always blames his tools' , I decided enough is enough and I will just fly the helicopter and get on with the next project.

 

[D.O.G.]

You have to remember that the numbers in the manual are just reference numbers to go by. If you try match their numbers, you will be there all day. Like you mention, "Enough is enough" or you will pull your hair out. Unless you have no hair to pull...like me . Good luck and enjoy your flight. Video if you can.

 

[Harford]

Many thanks D.O.G.

 

[Geena]

Thank you for this advice. The issue was that it was the same blade, showing 0 degrees in one position and when rotated 180 degrees showed -2.3 degrees.

After taking Geena's advice I have measured the pitch multiple times in multiple positions, using an Align digital gauge, removing the gauge and zeroing after each reading. I have never achieved a consistent result. I convinced myself that the swashplate must not be level, went through the process of setting it up again - it was out but not by much. After all this, the results were as follows, measuring the same blade at 90 degree points, following the procedure outlined above :
Blade One : 0.5. 0.9, 0.8, 0.7
Blade Two : 0.6, 0.7, 1.1, 1.1
I then moved the pitch stick to full positive, full negative and back to mid point. Took the last two measurements again which were the 0.8 and 0.4.

Having not achieved a perfect result, and not wanting to succumb to the old adage 'a poor workman always blames his tools' , I decided enough is enough and I will just fly the helicopter and get on with the next project.

You don`t have to zero after each reading, as long as you do not move the helicopter. Put the blades parallel to the tail boom, and zero the pitch gauge. put the gauge on the blade that is over the front of the helicopter and adjust the blade until you get it as close to zero as you can. Then....take the gauge off of that blade and rotate the head so the the other blade it over the nose....and put the gauge on that blade and adjust that blade to zero. Unless you have turnbuckle links, you will pretty much never get perfect zero.

 

[Harford]

Thank you Geena. Understand from what you are saying is to take two readings only, one on each blade and only in the one position, ie ignore other readings through the 360 rotation ? This is pretty much what I always used to do, just that this time with some time away from the hobby, I decided to get pedantic .. (much to my detriment as it turns out).