Topic Subscribe
WATCH  1 page803 viewsPOST REPLY
Boca Bearings . Encore RC . ExperienceRC
. .

Kyosho Caliber/Quest Neo-Caliber series

 >

Bad Vibe in Cal 30

BrentC

Senior Heliman

Utah, USA

Had my Caliber 30 out to the field yesterday. I am a noob so I have been getting the assistance of some experienced Heli pilots. Unfortunately nobody with Cal 30 experience. I had them hover my Cal to get everything trimmed and set up. Trimmed up beautifully, Heli would fly "hands off" for awhile. Put Roto Pod training gear on and another pilot hovered the Caliber to trim it out with the training gear on. He got things trimmed up with the gear on. He then attempted to hover again and the Cal 30 started shaking like an 'ol dog trying to pass a peach pit! Low frequency vibe which was really evident through the training gear. Had some excitement, vibe shook rx battery loose and it came disconnected so we had a runaway heli on our hands, luckily it just sat there at high throttle on the Roto Pod spinning away for 15 min. until tank ran dry. Thank goodness no harm to people property or Heli.
Couldn't find anything loose or bent. one min was hovering nice and the next bad shake. Any ideas?
My fellow club members advice was to get a Rappy
Thanks for your input
Brent

10-22-2006 Over year old.
Laurens

Key Veteran

Oegstgeest, NL

The trainings undercarriage might do that to your heli. Take it off or strap it on better.

WARNING

I had my heli crash due to the training undercarriage. Basically I was flying when suddenly the whole thing shook itself apart.

Edge rotorblades, Scorpion systems

10-22-2006 Over year old.
Chief_USN

Key Veteran

Chesapeake, VA

What your experiencing is a known issue with training gear. Your Cal30 might hover like it's on rails with no TG on but as soon as you put it on, it will start to shake. This happened to me and a buddy numerous times. It would shake so bad I was so uncomfortable that I would have to set it down. IMHO, what I think causes it is the downwash of the blades against the balls at the end of the rods. Once they get moving it transfers through the whole helo. I believe the RotoPod has 5 rods and one connecting point on the bottom of the heli. Correct me if I'm wrong. Only solution is to get rid of them. But if you really need TG, I would look at making a tic-tac-toe design with a hula-hoop. Basically you have two rods, one on each skid running length wise and two rods going perpindicular one forward and one aft. Attach the hula-hoop to the ends. Heres a pic from RR member "fliggyg's" gallery. He has the setup on his wife's heli. A guy at the field had a similiar setup and had no vibes.

Chad

Team HeliProz 12-14
US Navy Chiefs...Unity, Service, & Navigation to the Fleet since 1893

10-22-2006 Over year old.
HOMEPAGE  
dkshema

rrMaster

Cedar Rapids, IA

If I read your post correctly, the vibe showed up after you put on the training gear.

Two things come to mind. First, and foremost -- the Caliber 30 will give you a scary scary low speed wobble if your main rotor RPM is too low. Adjust your throttle and pitch curves to get the head speed up above 1800 RPM.

The second thing that comes to mind, is that the training gear only exaggerated the wobble from the low head speed, that's a lot of mass down below your heli's CG. Once it gets going, it will take a lot of work to stop it.

By the way, now's the time to make sure your battery won't fall out in the future. Wrap it in foam rubber (I use 1/4 inch foam rubber from Sig, used for wrapping receivers and stuff in my planes. Wrap the battery pack, then fit it into the compartment in the radio tray.

And secure the two halves of the battery connector. I put a piece of double-sided foam tape across the halves. Holds like a bear.

Dave

10-23-2006 Over year old.
The man

Veteran

at home

Try to change the resonance frequency of the training gear by adjusting the damping on the rotopod also. Some rubber band or tape might work.

10-23-2006 Over year old.
deafheliflyer

Key Veteran

Arizona

hi

Take training gear off, you dont need it.

I never used it whilst learning.

Crash-Prone and overcoming it!!!

10-23-2006 Over year old.
Lacster

Heliman

Corona, California- USA

Dave is right. Headspead is a big issue. Adding the weight of the training gear effects the pitch and throttle. I'd say bring the throttle numbers up 10% with the training gear on. Make sure your blades aren't too tight or loose. Has this heli ever downed? Is the training gear centered and somewhat balanced? Headspeed examples:
1700 hover, 1800 normal flight, 3d to auto 2000. It works for me. I recommend a GV-1 to everyone, maintains constant headspeed, displays headspeed, and YOU set and control it. I should get $1 from Futaba everytime I recommend this product. HE HE HE.
Lacster
Thank you, please drive through.

10-23-2006 Over year old.
BrentC

Senior Heliman

Utah, USA

Thanks all for the input! The way the legs on the Roto Pod were shaking, I thought that it was definitely contributing to the problem. I have it set up in the tripod configuration, would setting it up in the straight out horizontal position help things? Or should I just suck it up and go for the hover with it off?
I think head speed is definitely a problem. I didn't get to hover it, but those that did felt that it was bogged down. I am @ 4200 feet with OS 32 Cool Power 15%
My help set my Cal 30 up with:
-2 to + 10 Pitch
Throttle curve is :
1 = 6%
2 = 25%
3 = 50%
4 = 75%
5 = 100%
Pitch curve is:
1 = 25%
2 = 50%
3 = 62%
4 = 75%
5 = 100%
Swash is Ail 70%, Ele 70%, Pit 46%
Remember they are Raptor drivers.
Thanks again,
Brent

10-23-2006 Over year old.
The man

Veteran

at home

If you bought it might as well use it for a few tanks more until you are comfortable for hovering a tank without touching the ground. Changing the config on the rotopod and the RPM should solve it.

10-23-2006 Over year old.
The man

Veteran

at home

Lower the pitch curve should increase RPM also.

10-23-2006 Over year old.
Lacster

Heliman

Corona, California- USA

Brent, the caliber manual recommends to hover with pitch rate of low 0, center 6, high 10. These are just guidelines. I would say KEEP the training gear (all 5 legs attached) until YOU are ready for them off. It has been 4 1/2 years since I used training gear, but I remember how much it helped. Took me a month to be comfortable without it. Eventually, you get it and won't need it anymore. Take your time, practice makes perfect. Oh yeah, throttle percentages are too low. Try to keep the numbers close so that it doesn't bog down. Example (before GV-1): 30, 45,60, 75, 90. Headspeed @ 100% is usually in the 2100rpm range, might be too fast. Hope my input helps.
Lacster

10-23-2006 Over year old.
dkshema

rrMaster

Cedar Rapids, IA

This is more of a general setup post for you.

Are you using a pitch gauge to set your heli up? For some reason, your swash pitch setting of 46 just seems way too low. If you are not using a pitch gauge on the bench, STOP, go get one, learn how to use it, then USE it.

Among other things, you may want to review your linkage and control system setup.

You might want to read through my setup instructions (third and fourth posts) in this thread:

http://www.runryder.com/helicopter/t206926p1/

to get the servo and head controls set up properly. This is the basic starting point for any Caliber setup. A good mechanical setup will go a long way toward making your machine fly right.

My second reply in this thread ought to help you sort out some basic pitch and throttle curves to get you started off on the right foot.

http://www.runryder.com/helicopter/t206926p1/

Remember that just because you have done a "3D" setup on your heli, you're not stuck with having to fly 3D. The setup only gives you the optimum mechanical setup. The pitch and throttle curves that you put in your TX determine the type of flying you'll be able to do.

Dave

10-23-2006 Over year old.
BrentC

Senior Heliman

Utah, USA

Thanks all for your help! I put the Rotopod down in the horizontal position and took it out this afternoon for some hovering. I also adjusted my throttle curve so the numbers were closer together. I checked my pitch with my pitch guage. Runs -2 to +8. I also glued the foam and wire tied my rx battery into place.
Ran 4 tanks through it. It still will get the shakes which is definately from the Rotopod. It wasn't constant but I noticed it in ground effect. If I hovered out of ground effect it smoothed right out and it hovered like it was on rails. Hovering is comming along but I still was glad to have the Rotopod on. Glad I didn't listen to the Raptor boys, and buy a Raptor, I love my Caliber!

10-23-2006 Over year old.
dkshema

rrMaster

Cedar Rapids, IA

FYI -- Light-weight Training Gear. Total weight is 2.4 ounces. All you need is two fiberglass arrow shafts, four wiffle golf balls, eight nylon zip ties, some heavy duty cord, and epoxy.

They are connected to the skids using more nylon cable ties. Easy on, Easy off. Low profile, effective, and very light.

Dave

10-24-2006 Over year old.
BrentC

Senior Heliman

Utah, USA

I wished I would have seen the hula hoop or gear made from fiberglass arrow shafts before I shelled out $60.00 bucks for the Rotopod. The Rotopod has carbon fiber legs which allow it to flex absorbing some of the impact with terra firma, unfortunately this is what also allows it to start oscillating. While in ground effect, the down wash from the rotor combined with the air rising as it hits the ground start the legs to shaking.
My head speed was probably low also. Increasing the values in my throttle curve helped out. I will have to look into a GV-1.
Thanks again all for your help!
Brent

10-24-2006 Over year old.
WATCH  1 page803 viewsPOST REPLY
JR AMERICAS . HeliDirect . Heli-Max
. .

Kyosho Caliber/Quest Neo-Caliber series

 >

Bad Vibe in Cal 30

 Print TOPIC Advertisers 

Topic Subscribe

Sunday, November 23 - 6:36 pm - Copyright © 2000-2014 RunRyder   EMAILEnable Cookies