Woodstock Glider

On Apr 7, 7:36 pm, wrote:
On Apr 7, 3:03 pm, JJ Sinclair wrote:

I believe theWoodstockhas an aerodynamic twist that allows the tip
stall later (slower) then the root. I believe the airfoil was derived
from the Gother 549 (modified by Erv Culver) then it blends into USA
35B at the tip. I flew the prototype and it didn't have a tip stall.
JJ

wrote:
Thanks Guys

Correct me if I'm wrong, but there is no washout in this design is
there?

I'm looking at the plans, and there is no Washout, that I can detect,
which is why I'm asking.
The spar cutouts are exactly the same relative position on all the
foil profiles, with no twisting.
I am also an Aerospace Engineer, been working mostly mechanical for
the last 8 years so my aerospace brain has cobwebs, but I do know how
to read a drawing, my guess is it was this way for ease of
construction.
I'll re-read the assembly manual again.
I scanned sheet one of the 13M drawings and have the foils now in a
DWG format.
What I'll do is use Pro/E to loft between foil 1 and 20, then insert
each foil from 1 to 20 at station, then generate cross sections at
each station to see if they all meet up.

The original 12-meter Woodstock wing has no twist. Irv Culver
(Lockheed Skunkworks) did the airfoils at the request of designer Jim
Maupin (both now no longer with us, regrettably). Wingtip/aileron
stall protection was secured via reducing the percent section near the
wingtip. It's in the manual. Woodstock wing stall characteristics (at
least for the original 12 meter wing, which I built and flew) were
absolutely delightful: first time I stalled my n20609, on her maiden
flight, I broke out loud laughing. Perfect stall behavior; as mannerly
as it is possible to be. Despite low wing loading, the Woodstock
feels as much like Libelle as it does a SGS1-26. Easier to keep
rightside up in turbulence than a 1-26 in turbulence to boot,
particularly on aerotow.
Safe soaring,
Bob Wander

On Friday, April 4, 2008 12:35:37 PM UTC-4, wrote:
Hello

I have had my glider plans for approximatly 9 years now.
My question is, does anyone know the Airfoil used by the Woodstock
Glider?
NACA ###?

Thanks
Herbie

Dear Sir:
Is there any way I could buy a copy of your complete set to build woodstock glider?

Thanks Theodore R. Hansen

I have one of the earliest set of plans; the airfoil sheet is a full size template that you glue (contact cement)to a piece of 3/4" plywood. Each rib has its own profile printed inside the previous one as it tapers toward the tip. From this template you trace and sand the root rib first then sand the template to the next line and trace the next rib and so on. You keep sanding and tracing all the way out to the tip rib profile. THERE ASRE NO COORDINATES given or in anyway documented for any of the rib profiles. I recall a conversation I had with Jim in the late 1980's, I remember him telling me that when it came to the airfoil development, he said that Irv said "let me run the numbers". He came up with this design/method and Jim did as above to build the prototype.

The only parts I ever made for the airplane are the root ribs and the template itself. The original prints including the full size rib template drawing are the old style diazo prints and not accurately copyable; further, my print is used up to make the template. I suppose I could resurrect my project and make all the ribs, digitizing as I go. I estimate I could do this with an accuracy of approximately .05" which should be good enough for an airfoil working at these reynold's numbers as long as everything is "nice and smooth", as professor Alex Strojnik once told me; (see Low Power Laminar Aircraft Design/Structures/Technologies) Recognize that this will be quite time consuming. If anyone wants to seriously pursue this, contact me @ bpkuenen(at)gmail; I don't read these threads often

Hi. Did you ever follow through with the wing rib patterns or templates. I'm looking to start a build this summer. Any time savings on templates would be greatly appreciated and worth a financial fee to me. Turns out my plans are a copy from years ago so I dont really trust their accuracy. Either way, thanks for your time. Mark

On Thursday, May 10, 2018 at 8:36:39 PM UTC-4, wrote:
I'm looking to start a build this summer. Any time savings on templates would be greatly appreciated and worth a financial fee to me.

Something to think about. People who're building boats out of marine plywood often have their plywood cut out by laser. You can get your Woodstock paper pattern for ribs professionally scanned, then send the file to a job shop to be cut out. This is quite common for boat builders who're building from both traditional and new designs. It is cost effective because of the time savings and precision. The laser cutter can insure that the ribs for the left and right wings are identical, and symmetry is important.

Google for 'custom laser cutting plywood'. You can send your file to multiple shops for competitive bid.

On Thursday, May 10, 2018 at 7:16:17 PM UTC-7, son_of_flubber wrote:
symmetry is important.

Balance is important. Symmetry is way overrated, and I have the check templates to prove it.

--Bob K.

On Thursday, May 10, 2018 at 11:35:16 PM UTC-4, Bob Kuykendall wrote:
On Thursday, May 10, 2018 at 7:16:17 PM UTC-7, son_of_flubber wrote:
symmetry is important.

Balance is important. Symmetry is way overrated, and I have the check templates to prove it.

--Bob K.

If I might suggest, have them cut on a CNC machine, not burned on a laser cutting machine. Adhesives don't stick well to charred wood. I have a set of Wood stock parts, even completed spares that I cut by hand on a bandsaw, maybe 30 years ago...other ships got in the way and I never got around to assembly...plans are sometimes procrastinated by life. However it is a very straight forward process, tack the drawing to a piece of HARD masonite. Cut to almost the line then sand to the line. Tack two sheets of the 1/4 inch Marine ply together and trace the master pattern onto the stacked plywood. Rough cut (within an 1/4 or a 1/2 with a hand jigsaw)then cut and sand to the line. Trim the master pattern to the next rib and do the same for all the ribs. You can make a second set of master patterns by making a second master pattern with the sacrificial pattern each time. Please feel free to contact me should you like.
Jeff

On Thursday, May 10, 2018 at 11:35:16 PM UTC-4, Bob Kuykendall wrote:
On Thursday, May 10, 2018 at 7:16:17 PM UTC-7, son_of_flubber wrote:
symmetry is important.

Balance is important. Symmetry is way overrated, and I have the check templates to prove it.

--Bob K.

Please say a little more about how this works. I was thinking that precision and symmetry affects the left right balance in an aircraft.

On Friday, April 4, 2008 at 4:35:37 PM UTC, wrote:
Hello

I have had my glider plans for approximatly 9 years now.
My question is, does anyone know the Airfoil used by the Woodstock
Glider?
NACA ###?

Thanks
Herbie

How could I join this group?

Does anyone have available the drawings for the long wings. I bought an original set of drawings from
Jim in the mid '80,s (#58). The only thing I ever started on the project is the wing rib template , before I got side
tracked on a Wittman Tailwind (very fast) and a Buttercup . Since retiring and having sold both my interest is again
peaked in this glider, but if it makes a difference I'ld like a higher performance wing.

Tailwind888WT