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Conference vmszoo::rc

Title:Welcome To The Radio Control Conference
Notice:dir's in 11, who's who in 4, sales in 6, auctions 19
Moderator:VMSSG::FRIEDRICHS
Created:Tue Jan 13 1987
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1706
Total number of notes:27193

1626.0. "Rutan Long-EZ" by DNEAST::MALCOLM_BRUC () Mon Sep 12 1994 13:13

    This Note will be about the overall building and constuction of the
    Rutan "Long-EZ". This will be open for discussion and would request
    open debate. My phone call with the VP about the flying charactistics
    he said you "should" get a radio with Dual Rates. Saying you need full
    rate when taking off and landing but when the plane is flying switch
    to half. The wing and rudders are all foam and are sheeted with bulsa.
    He recommends covering the plane in/with fiberglass to add strenght.
    I have never used fiberglass so I'm a little shy about using it. Could
    use some scrap pieces of .045 birch plywood from my Ultralight. Then I
    could use Monocote(?) or something other than fiberglass (paint?). I
    will be using a Royal .46 BB ABC Schnuerle engine. 
    This will be my winter project hope to have lots of fun with it!!!
    
    Bruce
    
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1626.1What is Wing LoadingLEDS::WATTMon Sep 12 1994 13:448
    Bruce,
    	What is the wing loading on this project?  Some scale projects
    produce a pretty difficult model to fly if the loading is too high. 
    Canards can be tricky if it stalls before the wing.  You can run out of
    elevator on landings.  Maybe why dual rates are recommended.
    
    Charlie
    
1626.230411::REITHJim WRKSYS::Reith MLO1-2/c37 223-2021Mon Sep 12 1994 13:487
    Bruce, could you post some of the other specs on the model? weight,
    dimensions, wing area... I do like the Long EZ (I almost had my wife
    talked into one before a local rolled his into a ball near the house,
    killing himself)
    
    I hope to be able to follow the construction this winter (my next
    contract is looking more and more like it'll be outside DEC)
1626.3Advantage of RCLEDS::WATTMon Sep 12 1994 13:575
    That's the beauty of RC.  You walk away from all of your crashes....
    unless you manage to crash into yourself. :-(
    
    Charlie
    
1626.4It ain't over yet 8^)30411::REITHJim WRKSYS::Reith MLO1-2/c37 223-2021Mon Sep 12 1994 14:011
    Yeah, and you get to practice your composite layup techniques 8^)
1626.5DNEAST::MALCOLM_BRUCMon Sep 12 1994 16:2014
    This Long-EZ is a 1/5 scale version. 62.6" wing span, Weight is
    6-7 lbs. and the wing area is 630 sq. in. Dave did say that you need
    maximum elevator movement, or it will stall on landing. Maybe when I
    get it built I'll bring it down for it's maiden flight.(before I re-kit
    it!!) ;^(
    This plane also can have the front wheel to retract. 
    How does the weight vs wing area sound?? I'm sure it's not trainer
    type?? 
    I would like a discussion on covering this bird. Would .045 birch
    plywood be to heavy or is fiberglass the only way to go??
    
    Bruce
     
    
1626.6VMSSG::FRIEDRICHSI'd rather be flying!Mon Sep 12 1994 17:0231
    I've never worked with birch..   I guess the real question is, what 
    are all of the layers between foam and the clear coat?
    
    Normally, it would be something like...
    
    	foam
    	balsa/obeechi/?? sheeting
    	fiberglass cloth (with polyester or epoxy resin)
    	Layer of poly or epoxy to fill grain
    	paint
    	clear coat
    
    If you replace the sheeting with .045 birch, you still need to seal
    the grain.  How much stronger (or weaker) it will be with the
    birch I can't answer.
    
    If you want to replace the paint and clear coat with Monokote, you
    could probably do that.  But you still have to have sheeting underneath
    it.  You might want to increase the thickness of the sheeting slightly
    so that you do not melt the foam and you have a bit more strength.
    Be careful though..  If they are sending you pre-cut foam core wings, 
    then you might want to use the layers they suggest so that you do not
    change the airfoil too much.
    
    Fiberglass and paint is more difficult but the results are worth it.
    Look up the earlier note titled "Let Us Spray" (#288, I think) and it
    talks all about fiberglass and paints.
    
    cheers,
    jeff
    
1626.7Pretty High Wing LoadingLEDS::WATTMon Sep 12 1994 18:007
    at 7 lb, I work it out to 25.6 oz/sq ft.  This is high wing loading but
    not unflyable.  Keep it as light as possible or you will have a
    handful.  Make sure that the CG comes out EXACTLY where it's supposed
    to without needing added weight.
    
    Charlie
    
1626.8The GremTwin flew at near this wingloading...30411::REITHJim WRKSYS::Reith MLO1-2/c37 223-2021Mon Sep 12 1994 18:5411
    Well a normal Gremlin wing is 588 sq inches and my twin was 6 pounds
    and I felt that it was on the verge a bunch of the time. The big thing
    to remember is to keep the speed up and stay away from stall speed.
    Yeah, I guess I'm interested 8^) I personally will probably use obechi
    (.024") with epoxy and maybe some CF and glass under the skins and then
    the Red Devil spackle and water based poly for a sealer/finish/ I'd
    then spray the final surface with epoxy paint. I would stay away from
    polyester resin on a foam project because if ANY of it gets into the
    core, you have a hollow wing real quick. I never trust that my epoxy on
    the sheeting is enough of a barrier (plus I don't like using the
    polyester resin indoors during the winter building season)
1626.9Not that ExcessiveLEDS::WATTTue Sep 13 1994 08:437
    There are plenty of scale projects at this wing loading - but most are
    larger.  High wing loading is worse on a small plane than on a larger
    one.  I agree with Jim on construction technique.  I use epoxy
    exclusively for glassing and I would sheet and monocote the wings.
    
    Charlie
    
1626.1035989::BLUMJWed Sep 14 1994 11:132
    I have done experiments using 1/64"(.016") birch to sheet foam wings.
    Unfortunately it comes out pretty heavy.  Use balsa or obechi.
1626.11DNEAST::MALCOLM_BRUCMon Sep 19 1994 16:0824
    
    Recieved the kit last friday night. Opened the boxed and every thing
    looks very nice. The wood was grade "A" no warping, checks, or twists.
    There was some problems with the foam but nothing a sanding block
    couldn't fix. 
    The wing comes in 6 pieces, "the root, middle, and tip (8 counting
    the rudders.
    What else has caught my eye is the tolerances. Measurements like 
    5. 21/32"
    There is also a "Diagram of Measurements for the proper winglet
    (rudder) positioning". This has 5 different measurements to comeup with
    the right angle of the winglet.
    I will say this plane will take all winter to do it right. 
    You can also order for 12.95, a scale documentation package. In the
    package you get an 8x11 copy 3-view drawing of Mike Melvill's Long-EZ,
    7 3x5 color photos of the plane from 6 different angles, a two page
    letter from Mike stating the flying characteristics including his
    airshow. Also a design and material for a canopy-stay...PLUS a detailed
    drawing showing size and location of 6 "VORTILONS". These are used to
    staighten the airflow over the wing. And last a reference list of mag.
    articles which feature the Long-EZ. Looks like a must.
    
    Bruce
    
1626.12DNEAST::MALCOLM_BRUCWed Mar 29 1995 17:2024
    
    
    Well I've got two more days as a DEC employee so I better try and fill
    ya'll in on the plane. 
    
     The plane went together very easily. The hardest part was joining the
    wing sections and COVERING!! That is a pain in the butt! Everything is
    going OK with the covering it just takes a long time because it's my
    first time.....
    
     All I have left to do is to paint it, add some servos, and she is
    ready!
    
    I'm not sure that I am. 
    
    I'm going to paint the canopy a dark bronze, the plane will be White 
    with dark green trim, and I'm using Krylon paint. This being a pusher I 
    have little concern of fuel proofing.
    
    It is a very pritty ship!!
    
    Bruce
    
    
1626.13RANGER::REITHWed Mar 29 1995 17:3813
Hi Bruce. Where ya headed? Gonna have email access?

Thanks for the update. I hope to be able to see that plane on a visit to Sidney
sometime.

I'd worry about fuelproofing even still since it isn't too hard to spill fuel
while filling/topping off a tank. Also, handprints might be tough to get off if
you've got gooey hands from dealing with the stuff. Probably not a problem to
shoot a coating of K&B epoxy clear over the whole thing once you're done.

Best of luck and keep in touch.

Jim
1626.14DNEAST::MALCOLM_BRUCThu Mar 30 1995 09:2519
    
    We've been sold to the highest bidder....SCI Systems. 
    
    My job will stay the same for now but as you all know things could
    change.
    
    It is still up in the air if we will have e-mail OUTSIDE of this plant. 
    
    Probably not!!
    
    I would like to thank all of you for the indepth knowledge of this
    great sport you've shared over the past few years. I hope if/when I
    get some free time I can get down south to see ya'll again. Take care
    and may God bless!!
    
    Bruce
    
    
    
1626.15Be careful with KrylonWMOIS::WEIERKeep those wings spinning!Thu Mar 30 1995 10:0323
    
       Bruce,
    
           If you have been keeping up with my entries in the "Let Us
    Spray" note, you will see that the Jury is still out regarding Krylon.
    In fact, I am still in the middle of testing the Krylon clear. I have
    now let it dry for 5 days, tonight I will take a portion of the test
    piece and expose it to raw fuel. I will delay "fuel testing" the 
    remainder of the test piece for another 2 days.
    
      If you are just putting a base coat on, Definately use something like 
    Century 21, Formula U, or even rustoleum, all of which are fuelproof.
    If you are using a clear coat, K+B seems the way to go to ensure both
    fuel proofing and appearance.
    
       Jim R. is right, just fingerprints/raw fuel spills could wreak the
    finish. I would hate to see the finish on a nice looking Long Eze get
    damaged. 
    
        Good luck in your future modeling and job activities.
    
                                                            Dan
    
1626.16DNEAST::MALCOLM_BRUCThu Mar 30 1995 10:2913
    -Dan
    
    Yes I have been reading with antisipation on the "let us spray" note
    hoping to find an easy way out! The clear coating turning yellow scares
    me. I was hoping that the results were in with the Krylon before they
    unplug the notes file.
    
    I am using Krylon primer now and still sanding if rustolium IS fuel
    proof then I might switch to that, I'm looking for a perfect spray
    job out of a can and I know it won't happen.
    
    Bruce