(04) Rib Jig / Buttercup ( Mike )

[planecrazzzy]

         Hey Guys,
                    Just    when you thought this "thread" couldn't get ANY longer....
I'm doing another "stage" to the ribs....Putting the Gussets on the 3/4 Ribs....
Here's some pic's...

                          Gotta Fly...
                                          Mike & "Jaz" in MN   Shhhh, Jaz is on my lap sleeping....
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[jerry hey]

Mike,  I have not figured out this forum yet,  been on it nearly two  minutes.  I am not able to view your photos.  Anyway, I am very interested in Buttercup and have been having difficult contacting Earl.  Could you  send me some basic data:  empty wt, gross,  wing span and length.  Thanks if you do and thanks if you don't have the time.     BTW, my email is jerry@jerryhey.com    If you send photos, perhaps to me personally would be more likely to succeed.  
 jerry

[planecrazzzy]

Hey Guys,
                 I noticed before that my ribs had a little "dead spot"

They kind of flattened out from the normal curve.....

At first , I blamed it on myself....Figuring that I should have

soaked the bottom pieces of spruce....

 One day I was looking at the Jig that I used.... and I was looking
at it from an "odd" angle..... I saw the lines curving back and forth
like a SNAKE.....

 Just so happens , that my "pegs" hit "high" on both ends of the
snake....and "Low" in the middle.... Which gave that area a FLAT
spot.....You can't tell unless you look down the rib...

   I "Tried" to take pictures of it.... But because of the angle,
the camera wants to focus up close...

  If you REALLY want to get a GOOD look at it.... Pull out your
Rib pattern , lay it on the table "flat" , an look down the print...
Don't stand back and look at it...put your eye close to the table...

 It's a simple fix....as long as you know it's there....

      Gotta Fly...
                        Mike & "Jaz" in Mn ( With "NEW" Airfoil )

[JoyceBrown25]

Okay, so let's start at the beginning - rib building. I'm wondering about the braces, what was the process you used to get the joints cut just right so they fit nice into the corners. I'm thinking that once I order the material I just get a bunch of sticks and wood that I am to tap into my vast knowlege about building planes and just wittle away until the Buttercup shows up. Ok, it's late and I'm a bit sarcastic. But really - about the joints. Thanks.
Joyce

Here's an update.... Need 14 of these 3/4 Ribs....Half way there...
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                      Gotta Fly...

[planecrazzzy]

I'm not sure what you mean by "Braces".... The "truss" pieces ?

Get the length cut.... hold the piece where it goes... mark it with a pencil... use a disc sander ( see page one )

try to get the pieces to fit good.... if they're too tight.... sand them a pinch more... you don't want too tight...

I made one side fit at a time.... hold it parallel, just above it's location

If they turn out too loose..... make a shorter one out of it......( Make the longer ones first )

 I shaped one at a time... one rib at a time.... They get easier

Note... Make them fit fairly good.... They DON'T have to be perfect... They get gussets covering them...( get them close )

                                Gotta Fly...

We can give some good help here:  
https://groups.io/g/ButtercupSTOL
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[JoyceBrown25]

Yes, this is exactly what I meant. Thanks for the reply and help.

[planecrazzzy]

Hey Guys,
I haven't seen this one being done.... Most Jigs can't do it...

I put a piece of cap strip in my Rib Jig... bent it to the shape of the Root rib...

Then Penciled it in.... I did this for the Bottom piece too...

Then I drilled holes for "Stainless steel pegs" like the other ones I'm using ( 3/16" round )

and waala.... Root Rib Jig...

I've got Both ribs framed and plywood glued on one side.... I need to check the "Fit" before I close it up with another

piece of mahogany plywood...

Here's some Pix
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. Gotta Fly...
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[planecrazzzy]

After cutting the holes bigger with my router ( mounted on a table )

I got the ribs to slip into place.... The ends of these spars can move ( slightly )... So before I epoxy these ribs in place,

I will be putting the wings back on the Fuselage...and I'll leave it like that until the epoxy dries...

With the tight tolerances , it's the only way I can be sure...
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Gotta Fly...

[planecrazzzy]

Hey Guys,
After "Fitting" the Root Rib onto the spars.... notching out the area for the Plywood and metal Wing mount

I clamped the Root Rib onto the fuselage.... I could see I need to grind the shape of the rib to fit the fuselage better...

But I also needed to add more cap strip , before I grind it...

Gotta Fly...
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[planecrazzzy]

Just catching up.... After everything looked good , I then put the plywood skin on the other side of the root rib...sealing it.
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Then after it was cleaned up... I epoxied it onto the spars , and put triangle pieces for strength...

Now the spars are held in place good...
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Gotta Fly...
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[planecrazzzy]

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Hey Guys,
This is how the Rib Jig ended up.
I didn't drill each stage (3) until I needed them.
Now , any of the three styles of Ribs can be made.
Just tap the other pins down...or drive the pins out.
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Notice the Diagonals don't need anything...There not going anywhere stuck in those corners
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Notice the Vertical pieces , held by three pins... Capped off with a pin at each end (Top & Bottom)
Can't be much simpler...
This made it easy to lay down wax paper for Epoxy
If someone was REALLY ambitious... They could STACK these ribs , I wouldn't put more than two...But three COULD be set each lay-up
The FULL Rib would give more trouble... One at a time is plenty...There are only 4
Root ribs...well , there's only 2
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Little note... I used Stainless steel ....Someone told me they used Steel Pins
and was having rust issues.
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If there are any mistakes drilling the JIG ( KEEP IT FLAT DURING DRILLING )
Just put a little glue on toothpicks...drive them in the hole until you have it packed.
It will hold itself to continue , the glue is just an added bonus , not needed.
I did this type of repair on one hole...I drilled on the wrong side of the line...
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I'm amazed how complicated some jigs can be... Then , "Oooops" Didn't think about epoxy weeping into those moving parts.
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Steve Wittman LIKED Light & Simple.
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Gotta Fly...
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PS The Last rib I made were the Root Ribs , in the pictures , you can see a peg was removed to clear the cap strip
3/16" holes , 3/16" pins... They fit snug... tap out easy....easy back in also.