View Full Version : CCPM on thr Hurricane
Cralis
11-09-2007, 07:47 PM
OK, that time of my heli build has arrived.
At centre stick, I'm getting +5 degrees pitch. I need to get that to 0 degrees. I have the CF version. Can someone who has managed to get good 0 degrees at centre stick, tell me your servo link lengths?
OK, that time of my heli build has arrived.
At centre stick, I'm getting +5 degrees pitch. I need to get that to 0 degrees. I have the CF version. Can someone who has managed to get good 0 degrees at centre stick, tell me your servo link lengths?
You need to download Finless video on CCPM alignment and watch it. You suppose to center the stick and adjust all the link until the swash plate is leveled. Only then you adjust the link that control the pitch so that both blade pitch is at 0 degree (This is the last step) I am over simplifying the whole CCPM setup procedure here. The whole video goes into a lot more detail on CCPM setup. You should watch it a few times... I did.
GL,
Dan, KE6D
Cralis
11-09-2007, 07:58 PM
Is that the video where he sets up an Trex450, or does he have a CCPM setup on the hurricane video?
Is that the video where he sets up an Trex450, or does he have a CCPM setup on the hurricane video?
I believe he has one for T-Rex 450 and one for the Hurricane. The principle is the same. I didn't watch the one for the Hurricane, but the one for the T-Rex is similar. To set it up correctly, you program your transmitter to default values (or whatever Finless recommended), then move the collective stick to center. Adjust the links (6 of them - 2 for each servo) until the swash plate is level. Eyeballing is good enough.
You then move the stick to the bottom. Make sure that the swash plate does not hit the frame and has just enough space for the cyclic to work without hitting the frame. It the swash hits the frame during cyclic movements, the swash is leveled, but too low. You need to raise the swash up by either lengthening/shortening all the links by the same amount. Re-level the swash plate, then verify the low stick swash/cyclic operation. Keep doing it until the swash plate operate freely at the low collective stick position.
Verify the high collective stick to make sure the swash plate does not hit the washout block also.
Use travel limit adjustments for the elev and aileron to adjust for CCPM interaction.
GL,
Dan, KE6D
Cralis
11-09-2007, 10:15 PM
Thanks Dan.
Took your advice and also watched the videos.
Swash now straight. My arms were all over the place.
Got them all measured... all servo rods the same length as each other on the servos... and the swash is perfect now.
Was still getting -4 degrees on the blades. So adjusted the link to the blades a bit, and now sits nicely at 0 at mid stick, and I am getting +9 to -9. I think that's OK.
I have noticed though.. I can only run one servo rod for the pitch servo. I can only connect the lower one. The top one hits the caopy connector. So, is it safe to run with only one servo rod?
I've attached photos. A photo with the link off, and then a few trying to show the problem. I can lift the link that attaches to the servo enough, as it's hitting the canopy grip.
A majot design falw or am I being dumb here?
Pinecone
11-10-2007, 05:24 AM
With the Hurricane you need to watch the one for it.
But the Trex one is good for basic knowledge and should be watched by EVERYONE.
Mikej
11-10-2007, 07:02 AM
[QUOTE=Cralis;449285]Thanks Dan.
Took your advice and also watched the videos.
Swash now straight. My arms were all over the place.
Got them all measured... all servo rods the same length as each other on the servos... and the swash is perfect now.
Was still getting -4 degrees on the blades. So adjusted the link to the blades a bit, and now sits nicely at 0 at mid stick, and I am getting +9 to -9. I think that's OK.
I have noticed though.. I can only run one servo rod for the pitch servo. I can only connect the lower one. The top one hits the caopy connector. So, is it safe to run with only one servo rod?
I've attached photos. A photo with the link off, and then a few trying to show the problem. I can lift the link that attaches to the servo enough, as it's hitting the canopy grip.
A majot design falw or am I being dumb here?[/QUralis,
Looking at this picture http://static.rcgroups.com/forums/attachments/9/9/2/8/0/a1439608-144-IMGP3596.JPG
it looks as if the canopy bracket is on a little arm that will allow you to swing it out of the way - I can't see if you have this in your photo, but I think that it is what you need.
Mike.
Cralis
11-10-2007, 07:05 AM
Thanks Mike. Just found that now. Amazing! Great help! And it looks better! I have swivled the canopy connectors 90 degrees up, and now it lifts the back of the canopy, making the heli look better, and I can attach the rod no problems. Thanks Mike.
Cralis
11-10-2007, 08:10 AM
2nd hover attempt. Success!!
However, I'm battling with the tail.
The 401 light is on, so it's locked in HH... but if I don't put rudder, the tail is trying to swing left.. I'm constantly holding left rudder to keep the nose pointing straight. What could be wrong??
Mikej
11-10-2007, 08:43 AM
The way that is normally recommended is to set up the gyro in rate mode first so that you have no trim to get the tail to hold straight (do this by adjusting the ball links or moving the servo as appropriate). Once you have done this you should be able to flip into HH mode no problem.
Look at how Finless sets up the Telebee servo here http://video.helifreak.com/?subpath=finless/hdx300&filename=tail_gyro.wmv if you follow the same process you should be good to go.
Pinecone
11-10-2007, 01:54 PM
I currently have my H550 setup with the tail slider centered, like the Finless video on the Trex 450. Works fine.
I have had helis with the tail trying to move right, turns out loose tail hub, or belt pulley, etc. Not sure what would make it move left.
Crash549
11-12-2007, 02:15 AM
Watch all of the 550 build videos and you will see some solutions for the linkage length issues. I used the raptor links mentioned in this video and they work perfect. http://video.helifreak.com/?subpath=finless/hurricane550&filename=servos.wmv As for your 401 tail setup watch this one http://video.helifreak.com/?subpath=finless/hurricane550&filename=tailsetup.wmv Finless makes heli setup fun again!