Conference vmszoo::rc

    Mike,
    
    the Elektro-UHU uses 2 nylon bolts M4 (metric 4 mm outer diameter). I
    never had any doubt of these being insufficient, but I had one very
    hard landing on the wing tip (wing vertical due to gust) where both
    bolts sheared and prevented damage of wing or fuselage. I'm very happy
    with that dimension, but have no idea what size of american screw would
    match. Maybe you should just look into the future and go metric :-)
    
    One of my favourite arguments...:-)
    
    Hartmut

Send over a 4mm die and we'll rethread all our 1/4-20 wingbolts 8^)

A pair of 1/4-20s would work fine. You could probably get by with 10-32 bolts 
but why worry. the biggest thing is to make sure the wing bolt plate is strong 
enough so it doesn't pull out before the bolt shears.

I had used a single 1/4-20 and a pair of 6-32s on my open class Alcyone and 
even with some of the spear landings I did, I broke the 6-32s (rotation) but 
the 1/4-20 survived.

    Thanks.....the mod is cast!
    
    
    Jim,
    
     When can i see that acyone fly (2M)???????
    
    bye

Lamar may fly his tomorrow after work. Mine is being covered. I decided to 
get more involved with the covering job and I think I bit off more than I 
could chew. Didn't help that I lost a full week to the flu. It took me 3+ 
hours to do the bottom of the wing! I should have it finished for next week 
but then we need to decide on a place to fly. Lamar and I went out yesterday 
at lunch but Acton has a foot and a half of snow! We're going to try the 
empty LTN1 parking lot tomorrow on the way home. Gotta get than February 
flight in 8^)

    The 4mm nylon bolts used on the Graupner Uhu, which Hartmut
    mentioned, are available from Hobby Lobby for 20 cents each.
    The matching blind nuts are available at 30 cents apiece.
     
    I buy them 10 at a time, they are excellent for bolt on stabs
    as well.
    
                                                      Regards,
    
                                                      Jim

>                     <<< Note 1492.0 by RANGER::PITONIAK >>>
>                        -< Spectra Wing Attach Mods?? >-
>
>    Greetings,
>    
>     I just purchased a Goldberg Spectra and would like to modify it to
>    use a nylon wing bolt rather than the rubber band method detailed
>    in the assembly manual. Has anyone done this?

Mike - look close at the box and you will see it says Great Planes - not
Goldberg.  If it's a Goldberg - then it's an Electra which is a variant
of the Gentle Lady.

Anyway - George Mills had both a Spectra and a Spirit.  Since he retired
from RC I doubt he reads this notes file - but send him mail and you will
get the definitive answer.  I believe they removed the bolts to have room
for the motor/battery/speed control/radio/servos.

Bye          --+--
Kay R. Fisher  |
---------------O---------------
################################################################################

    I build one of these this winter.  this is my first plane.  I was able
    to coat mine in about 6 hours.  I would like to know how the mods work.
    
    I'll probably not fly till april.  
    
    Rob O

    In  order to get the bolt down block on place I would have to
    re-arrange the servos. Additionally, I would probaly have to add an
    access dore in the bottom to get at the battery (instead of removing
    wing bolts each time).
    
     I decided to leave it stock, and just get it into the air as is.
    
    Thanks for inputs.
    
    mike

    Mike,
    
    	I now have George Mills old Spirit. He originally had the wing set
    up to bolt on, but after a slightly cockeyed landing and breaking the
    side of the fuse out, he decided rubber bands would be better. I will
    be converting it back to nylon bolts. The servo's under the wing WILL
    have to be moved back about an inch to make room for the wing hold
    down blocks.
    
    	The plans aren't very clear regarding the bolt on option, but 
    basically you put a ply plate and balsa filler in the two center
    rib bays. By that I mean the "bay" formed by the root rib and the first
    rib out on each wing. The back of the bay is the spar. The ply plate
    goes in the center of each bay (depth wise) and fills the bay. In other
    words, make the plate the same size as the inside demensions of each
    bay. Epoxy in place using the leading edge and spar as front and back
    contact points, and the root rib and first wing rib as side contact
    points. Put balsa filler over the ply plate and sand to wing contour.
    Put sheeting ontop of this. Drill a whole through the balsa, ply plate
    and wing hold down block. Counter sinc the nylon bolt head through
    the balsa down to the ply plate. That way, the bolts are recessed
    and not sticking up.
    
    This is probably about as clear as mud, but depending on your flying
    skill, using rubber bands in the beginning is probably smarter anyway.
    
    
    Steve

You'll know when it's time to switch over to bolts when you do a 
loop or a zoom launch and hear that ever familiar CLOP when the 
wing lifts up and smacks back in (hopefully the proper) place.

Jimmy did this on his GL and the wing was almost 2" offset to the 
side. He made a very nice descending circle save.

    Steve,
    
     Thanks for the input. I figured that with no way to access
    the battery without removing the wing each time, i would fear that
    the wing bolt down block threads in the ply would take some abuse,
    and probably loosen up too much. I decided to leave this one stock,
    and if i like it, modify my next one to load batteries from benieth
    the fuse.
    
    thanks,
    
    mike