450 head conversion plus other questions.

[andrewt1971]

Hi,

I've done my mechanical conversion, just waiting for the postal service to deliver my sk360 now, thought I'd post a picture and see if anyone can spot any obvious problems. With the swash mixing at 60 across the board I get 10degrees cyclic and about 14degrees collective, which i'm going to dial back. The grips and pushrods are blade400, the head block needed relieving slightly to miss the webbing on the grips but otherwise a direct fit, the driver is from a piece of g10 and the alloy spacers behind the balls are there just to stiffen up the grip. They don't look as strong as trex ones put i'm not planning on putting a zillion RPM through them!

Now for the other questions! If this goes OK I'm going to put one in my Rotorworks G4 which when sat on it's skids has a serious nose down attitude, would that cause any problems with the initialisation and take off? Also in the manual section 5 page 11 it says you can use dual rates etc but don't exceed 100% travel, does that mean don't exceed 100% if that's where your end points were when you did your original setup? I ask as I was going to run my EPA's to 150% to get higher resolution on the radio link then dial back the servo travel in the sk360 if neccessary, does that make any sense? would I be wasting my time doing this?

Thanks everybody for your help.

Andy

[jrohland]

The setup looks nice and clean. I am slightly concerned the tabs on the blade grips where the ball links are mounted might flex under load. If they flex, the blade tracking could go in and out and, the blade angle of attack could vary unexpectedly.

It looks like your links are on the trailing egde of the grips. Remeber, your swash movement will need to be reveresed. That is, the swash will go down to get positive pitch. This is not a big deal but, be aware of it. It is very easy to change, just disconnect the links, rotate the grips 180 degrees and reconnect them to the opposite link.

What servos are you running on the collective? You said you are using the HDS 577 on the tail but, not what you are using on the swash. The servos will need to have a good amount of torque and should be accurate (digital).

jrohland

[andrewt1971]

Blade grips now flipped! There is a small amount of flex in the grip tab, i guess i'll find out if it's going to be a problem pretty quickly, I wonder if there is a problem with tracking on blade400's the forces going into the grip should be similar in the standard setup as I haven't extended anything on the grip. The servo's are currently low use hs-65's on 6v, if there not up to the job then i'll change them but i'm not planning on abusing the heli, it's more of an exercise to see if flybarless is for me!

[SpeedVision]

Originally Posted by jrohland

Now for the other questions! If this goes OK I'm going to put one in my Rotorworks G4 which when sat on it's skids has a serious nose down attitude
jrohland

My Mini Titan has Gorilla Gear Low Profiles. In order to keep the stock Titan veritcal tail fin, I had to spread the front skid and pull the rear skid together so skit tubes make a gentle "v" thus raising the tail giving it an G4/G5 stance. No problems yet, but I haven't had Hiller decay lower than 50% and auto trim is unchecked.

Maybe Skookum will chime in and share what the possible issues could be with a heli that has serious nose down and the SK tipped forward 3-4 degrees at takeoff...

[Skookum]

>...which when sat on it's skids has a serious nose down attitude, would that cause any problems with the initialisation and take off?

As long as the SK360 is mounted with its base at 90 deg to the mainshaft (parallel with the rotor disk) it should be fine. It won't care if the rotor disk is tilted forward when the heli sits on the ground, if that's what you mean.

>Also in the manual section 5 page 11 it says you can use dual rates etc but don't exceed 100% travel... I ask as I was going to run my EPA's to 150% to get higher resolution on the radio link then dial back the servo travel in the sk360 if neccessary, does that make any sense?

The manual says that to keep things simpler. If you want max resolution from your radio, yes you can use 150% travels on your radio and then set the travels to 150% on the Control tab in the setup software. Just be sure to use your 150% rate when you test cyclic pitch range while in setup mode (don't dial back servo travel instead!). When you are testing say cyclic pitch for aileron, it should show 100% pilot input for aileron.

[andrewt1971]

Well, It flies! The first hover was completely un eventfull, I don't know what I was expecting to happen but it just lifted off and sat in a pretty stable hover. During the following flights I got a bit carried away with the hiller gain whilst trying to improve the feel in the hover, slightly ambitious considering it's blowing 20+mph and gusting into the 30s I got cyclic wag after been hit by a strong gust of wind, not funny! The only thing I need to sort is a slow nose up down oscillation I get when turning from an upwind pass to downwind, only does it two or three times then stops but again that may be due to the gusty wind!

I'm pretty sure the rest of the fleet is going to get converted, once i've used up my stock of flybars!