Conference vmszoo::rc

    Since the Concept 30 DX has an autorotation bearing, there is only
    one thing I can think of that could cause the main rotor shaft to bind
    in both directions. There is a collar around the main shaft with 4 set
    screws sandwiched between the upper portion of the side frames near
    the upper main shaft bearing. I think one of these set screws must have
    backed out and is binding between the side frames preventing the main
    shaft from rotating.
    
    Also the Lazy Loopers flying club in Wrentham MA is having a
    helicopter fly-in this Sunday (Aug 20th). If you would like, you are
    more than welcome to bring the helicopter down and get help trimming it
    out. I can get you more information if you are interested.
    
    Wayne
    

    Thanks for the tip on the bearing; we'll check it out tonight.  And we'd
    love go to the fly-in, but unfortunately we're going white-water rafting
    in Maine this weekend.  How often do these fly-ins happen?  I'd hate to
    miss the only one this season...

    Alfred

Another thing to check is the plastic bushing that a part of the pitch slider.
If not lubed it tends to melt down with exactly the effect you're seeing.. 

>    Another thing to check is the plastic bushing that a part of the pitch
>    slider. If not lubed it tends to melt down with exactly the effect you're
>    seeing..
    
    An even better solution to the pitch slider problem is to
    replace it with the ball bearinged pitch slider. They always get loose
    and allow alot of slop in the collective.
    
    Wayne 

.1>Since the Concept 30 DX has an autorotation bearing, there is only
.1>one thing I can think of that could cause the main rotor shaft to bind
.1>in both directions. There is a collar around the main shaft with 4 set
.1>screws sandwiched between the upper portion of the side frames near
.1>the upper main shaft bearing. I think one of these set screws must have
.1>backed out and is binding between the side frames preventing the main
.1>shaft from rotating.

    We finally disassembled the helicopter over the weekend and found
    the collar you are referring to.  However, the problem was just the
    opposite of that you described.  The set screws were all too tight;
    losening them a bit allowed the shaft to rotate freely.   But are
    these screws supposed to be on tight?   We don't quite understand
    what this collar is for.  It's right underneath a bearing which is
    encased in the frame, but the collar just "hangs" out there in the
    open.  Can someone enlighten us?

.2>Another thing to check is the plastic bushing that a part of the pitch slider.
.2>If not lubed it tends to melt down with exactly the effect you're seeing.

    It looks like the bottom bushing may have melted, but we're not sure
    (nothing to compare it against), and now that we have losened the set
    screws, everything seems normal again.

.4>An even better solution to the pitch slider problem is to
.4>replace it with the ball bearinged pitch slider. They always get loose
.4>and allow alot of slop in the collective.

    Sounds like a good idea.  How much is this contraption and where can
    we find one?

    Our current problem (yes, the helicopter still hasn't flown) is that
    we have a servo that doesn't fit.  Here's the story.  When my brother
    bought the helicopter, they sold him a Futaba gyro.  However, the gyro's
    connectors didn't fit with the receiver and servos that came with the
    Airtronics remote control.  First we were told to get an on/off switch
    for the gyro which would solve this problem.  But the switch didn't
    solve the problem. (and we had to wait a week or so for it to arrive).
    They finally sent us an Airtronics gyro, which came with its own servo.
    But now this servo is smaller than all the others and does not fit in
    the bracket on the frame.  Arrghh!  This is getting frustrating.  Any
    ideas?  My brother will go to the hobby store (Eric Fuchs) again
    tomorrow, but we haven't been very impressed with their help and advice.

    Alfred

        Alfred, this will not help your heli problem(s) but will allow me
        to express the opinion that if I had anything good or positive to
        say about Fuch's stores and the under-trained or experienced
        poeple who staff them, I would have said it here.
        
        Andy (who tries to stay within Digital and conference guidelines)
        
        

    Gee Andy, you sound like a polititian :-).  I know what you mean,
    though, and we have come to this same conclusion ourselves.  But we
    are sort of stuck until we can find someone else to help us.  My
    brother got an application for an RC club recently, and it had a
    referral for a helicopter instructor.  I think we will try to follow
    up on this lead.

    Alfred

    The set screws in the collar MUST be tight. The purpose of the collar
    under the main bearing is to keep the main shaft from pulling up out of
    the bearings, and it also acts as a guide for the likages that run between
    the pitch slider and the mixing base. You have to make sure that none
    of the set screws are pressing on the pitch linkages.
    
    Kyosho also offers a machined pitch slider which uses balled bearings.
    They call it the "SE pitch slider". The slider and the required
    bearings are purchased seperately. If you would like, I can look up the
    Kyosho part numbers.
    
    Wayne
    

    As for the Airtronics servo not fitting the servo mount provided, I
    would recommend you call the Kyosho "helicopter hotline" (217)398-2834.
    They should be able to answer all your Concepts questions.
    
    Wayne.

    First of all, thanks again for all the valuable information.  With the
    help of this notesfile, one of these days this helicopter will fly (and
    no thanks at all to the folks at Eric Fuchs).

    >The set screws in the collar MUST be tight. The purpose of the collar
    >under the main bearing is to keep the main shaft from pulling up out of
    >the bearings, and it also acts as a guide for the likages that run between
    >the pitch slider and the mixing base.

    That's what I was afraid off.  Tightening the set screws prevents the
    shaft from turning, which means that we have another problem (probably
    the melted plastic bushing mentioned in an earlier reply).  We'll try
    to get the "SE pitch slider" instead of attempting to fix the current
    problem.

    Alfred

>>  Also the Lazy Loopers flying club in Wrentham MA is
>>  having a helicopter fly-in this Sunday (Aug 20th).

Wayne,
    Do the Lazy Loopers have any helo fly-ins scheduled
in the near future?  I'd love to go to one of these and
see if I could get the bug. I'm a fixed wing pilot (full
size, not RC) with a few solo hours in a Robinson R-22
who has always had an interest in RC Helo's. But it
doesn't sound like something to get into without quite
a bit of up front knowledge. 

Anybody else know of any fly-ins or scheduled RC meets
coming up?  Is there a note for upcoming meets?

 - Ford

The New England season is winding down. The last contest I'm aware of is the
Gremlin Contest this sunday at CMRCM in Westboro MA. Choppers aren't as
popular in these parts as some so generally you're lucky to have one event per
club, if that. Wayne's one of the main guys to talk to for choppers.

Jim (chopper pilot in training)

    The season is getting pretty close to the end as far as events go.
    However, I do fly year round, and if you wanted to meet over at the
    loopers sometime and see what choppers are like I'm sure that could be
    arrainged. I expect to go to the Gremlin Contest at Central Mass this
    Sunday providing the weather is at least remotely OK. Assuming it is,
    I'll have one of my helis with me as well.
    
    Wayne