CP Pro 2 is Killing me

[konceppt]

Hi all,

I recently had to change a main frame and then i had the esc burn out.
I have put it all back together but i cannot set it up.I never checked before but the servos needed a lot of subtrim to get them at 90.I levelled the swashplate but i need some measurements.I set my blade 400 up last night and the manual has all the linkage measurements and swash height etc.

The cpp2 does not have these measurements in the manual and i cannot get it right.My swashplate is level but to acheive 0 degrees at half stick,i have to wind the pitch ball links in as far as they go and its still 3 degrees off one side and 2 the other.
Then i tried to set the swash height to get -12 and +12 at full extents but that will not happen regardless of pitch value in swashplate mixing.

Its driving me crazy,If someone has measurements (linkages and swash height at half stick) you would really be helping me out.

Thanks
Ben

[John Shipley]

The way you set up a cp is like this...unplug both motors. Put your throttle stick at 50%. remove all trim and sub trim. Look at your servo arms, they should be 90 degrees to the main shaft. If they are not, remove the arm and position as close to 90 as you can. Now use sub trim to make them 90. Now, take your links and screw them in about 3/4 of the way in....this is not a critical measure at this point. What is important is that they are equal. Attach them to the heli....your swash should be level or very close. If it is slightly off, use sub trim to level.....you will not use sub trim again. Now, move your pitch up and down to see if you have full travel with no binding. You can adjust travel by either adjusting all of the links ie all go in or out.
Depending on what type of tx you are using, you can adjust travel in the tx too. ....J

[konceppt]

With my blade 400 you do it similar to that but you can also use the swashplate mixing to give you +10 and -10 and 0 degrees at half stick with a linear pitch curve.The swashplate has a set height at half stick.The blade 400 is manually perfect with no subtrim and perfect pitch but it seems impossible with the cpp2.

But obviously if my swashplate is too high at half stick then its never going to work.Thats why i need to know the swash height really.E-flite give you all the figures for a blade 400 but not for a cpp2

[erospawn]

I just got my CPP2.. its actually waiting for me when I get home from work.. If you like I can take the measurements of the linkages when I open the box and post here later tonight.

[konceppt]

Yes please!!

I am most interested in the height of the swashplate at mid stick (0 degrees pitch) and also if all the servo arms are at 90 degrees and the swashplate is level too.
If the heli isn't setup that way new in the box then maybe I am wasting my time trying to get it perfect mechanically.perhaps I should level the swashplate and set the rest on the transmitter.
Are you using the transmitter that is supplied with the heli or binding your own?
I am using a dx7.
Thanks

[John Shipley]

If you do what I posted your swash will be level. When your swash is level, then you try to get it centered on the main shaft. The only way to raise or lower the swash with the arms at 90 at center stick is to adjust the links. But you have to adjust all of them the same, ie all go in a few turns or all go out a few turns. You do this until your swash is in the middle, ie, equal travel up and down.
I fly both the CP and the SR's with a DX 7. The heads are very easy to adjust correctly. I have also owned 2 blade 400's. Every CP or SR I have owned was not set up right. All of them required tweaking. CP's have equal links, 400's do not.....so start with your links all equal and adjust from there......
An easy way to make sure your stick is at 50%, is to go into your idle up pitch menu for IU 1 and set it for 50 straight accross. Make your adjustments, then flip into IU2 and check overall travel. Do this untill you have it right. Be sure to reset IU 1 back........J

[erospawn]

I've had a lot of practice setting things up... Basically you need to set the transmitter on and let the servos fall where they may.. then set them to 90 degrees. Then turn on throttle hold, flight mode on -- (Unplug the motor wires is safest).. move the throttle stick to the middle. Make sure the swash plate is set to the middle of the main shaft. Take one linkage and set it so that it connects to the ball joint on one side. Then you do the same for the other side and the front piece such that the swash plate should now be level and in the middle of the main shaft. If you check the blades and they aren't at 0 degrees pitch with the stick in the middle, your swash plate probably isn't level.. Pitch linkages might be off too. So, after you set this up... move the stick all the way down, measure pitch.. move it all the way up and measure pitch again.. Adjust the pitch linkages so they match. I'm not an expert here so it's best to watch the videos to make sure it's right..

[erospawn]

OK.. so out of the box.. the servos are not set at 90 degrees... throttle hold on and flight mode on.. blades at zero pitch and swash plate is in the middle.

Linkages --- With the Heli's tail facing you --
Linkages -- from the servo connector to the middle of the ball joint.
Left 3.2cm
right 2.8cm
front 2.7cm

Thats out of the box...

[John Shipley]

A level swash plate has nothing to do with pitch. Your swash should be level in all positions until you add ail or elv. The swash moving up or down the shaft is what adds pitch.....these are different adjustments. Once your swash is level and your servos arms are at 90 at mid stick, the only way to center the swash so it is in the middle of the main shaft is to adjust ALL 3 links at the same time. If you only adjust one, the swash will tilt in one direction or the other. The CP heli has equal length links because the servo's are on the same plane. Many other heli's do not, ie the blade 400 and the align 450 V2 and sport.
You can also adjust the over all travel of your servo's with a DX 7 tx. This makes your servo's and swash level in all positions of the pitch range. To test if you heli needs this adjustment, you need a very good eye or a swash plate leveler or get your heli in a hover and do a verticle climb out. Does it go straight up or drft on way or the other? Do the same inverted. If your swash is level in all positions the heli will climb out straight up, unless the balance is off.
Once you have your swash level and in the middle of your shaft, then you adjust the pitch. Adjusting pitch is different than adjusting pitch travel in the tx. You adjust pitch to zero, by the links, you adjust overall travel in the tx......J

[konceppt]

I understand that,the problem I am having is that my swashplate is level but I cannot manually adjust the centre stick pitch to zero.I have to wind the pitch ball links all the way in,and they still won't get to zero,
So I know my swashplate is level but it's not in the middle of the shaft.at full throttle I only get 7 degrees max.But I can't raise the pitch value because it starts the servos buzzing.

What pitch value should I start with on swashplate mixing?
Also I need a lot (34) of subtrim on ail and pitch servos to get them at 90

[erospawn]

Originally Posted by John Shipley

The swash moving up or down the shaft is what adds pitch.....these are different adjustments. Once your swash is level and your servos arms are at 90 at mid stick, the only way to center the swash so it is in the middle of the main shaft is to adjust ALL 3 links at the same time.

I'm still pretty new to this so I am still learning. I think I read somewhere about the swash plate not being level being a possible cause the pitch on the blades didn't match on either side. But, from my understanding, the TX should be in flight mode and the throttle centered and swash plate centered on the main shaft... One linkage needs to be set when the swash is level, then start adjusting the other links so that the swash is level all the way round. So, yeah, the swash plate moving up and down controls pitch. Don't the upper links that attach to the flybar head help to track the blades, but also fine tune the pitch?

[konceppt]

Originally Posted by erospawn

I'm still pretty new to this so I am still learning. I think I read somewhere about the swash plate not being level being a possible cause the pitch on the blades didn't match on either side. But, from my understanding, the TX should be in flight mode and the throttle centered and swash plate centered on the main shaft... One linkage needs to be set when the swash is level, then start adjusting the other links so that the swash is level all the way round. So, yeah, the swash plate moving up and down controls pitch. Don't the upper links that attach to the flybar head help to track the blades, but also fine tune the pitch?

The upper links are the ones you use to track the blades and the ones you adjust to manually set both blades to zero pitch at half stick

[erospawn]

Right.. when the stick is centered, the blades should be at Zero pitch, in flight mode. The you raise the stick and measure the pitch and then lower the stick to measure pitch. This is where it gets iffy for me.. I think the values should match positive and negative, but how much pitch should there be? 10 Degrees? And if it's not the same on either side positive or negative, this is where I thought the swash plate not being level might come in to play..I mean a large value ...10 positive on the right side and say 12 or more on the left side.

[John Shipley]

Something is not right. Are you in TH?? It has it's own curves. If you are out of TH and in IU 1 and have the stick at 50%, the only adjustment you can make is to the links that go from your servo to the swash. As stated in post 2 on how to get your servo arms to 90 with the least amount of subtrim. It is possible, you rebuilt the head wrong and you are getting binding. The servo's should not be buzzing unless your hub is bottoming out either high or low.
If you can not get your swash in the middle of the main shaft, with the servo arms at 90 by adjusting the links from the swash to the servo's....something is wrong....hopefully it is that you are in TH..... If you can take a picture of the head....J

[erospawn]

TH does reset the servo's differently.. I had to set up my SR after banging the crap out of it.. and I remember unplugging the motor wires and setting it up without throttle hold on. So, I was incorrect in stating to put in TH as an alternative to unplugging the motor wires..

[konceppt]

Its not in throttle hold,its in normal mode with a linear pitch curve.
0,25,50,75,100 and a linear throttle curve 0,25,50,75,100

The servos are buzzing on full throttle because the servos are trying to pull the swashplate further than it can go.I am certain its because my swashplate isnt in the centre,i am going back to it today

[John Shipley]

I measured my links from the servo's to the swash and they are 32.7mm from end to end.....over all length tip to tip.....tip of the link to the tip of the Z bend.
I am not sure why you have a linier pitch in normal mode. This is usually a bad idea especially for a new pilot. The normal one would be around 43, 48, 50, 75,100. Idle up, IU is linier.
If you make your links the same as mine, and your swash is still not in the middle of the main shaft, you have another problem. Probably the servo's are not at 90 or your head is not on right.....but something else is wrong.......J

[konceppt]

Originally Posted by John Shipley

I am not sure why you have a linier pitch in normal mode. This is usually a bad idea especially for a new pilot. The normal one would be around 43, 48, 50, 75,100. Idle up,

Its linear because i am setting the swash up.I will adjust the pitch curve once i mechanically set zero pitch at half throttle and have an even throw up/down.

Once i do that i just adjust the lower end of the pitch curve to give me -2 or -3 on full negative pitch.

[John Shipley]

That is not the right way to do it. I have explained the right way to do it in an earlier post. ie, go into idle up 1, put the pitch curve at 50%. That way you know you are at 50%. If you are even slightly off at mid stick, it will throw off everything else. You might want to check out Finless Bobs tech video's on the front page of heli freak and look at "look here first" Check out the set ups. There are not any for a SR or CP's, but the 450's will give you a good idea......J

[konceppt]

Originally Posted by John Shipley

That is not the right way to do it. I have explained the right way to do it in an earlier post. ie, go into idle up 1, put the pitch curve at 50%. That way you know you are at 50%. If you are even slightly off at mid stick, it will throw off everything else. You might want to check out Finless Bobs tech video's on the front page of heli freak and look at "look here first" Check out the set ups. There are not any for a SR or CP's, but the 450's will give you a good idea......J

Why does it need to be in idle up 1?
I don't have a stunt mode programmed anyway,I am using a dx7 not the eflite transmitter.surely if my pitch curve is set to 50% at exactly half stick(using the graph and the 50 in 50 out info) then it makes no difference what flight mode it's in?

My idle up pitch curve is no different to my norm pitch curve at this point,I am just trying to get zero pitch at half throttle and an even +ve and -ve pitch value at full/closed throttle.
Then I set the actual amount of pitch I want using the pitch curve afterwards,once i know it's even?