DO NOT USE THE DRAWINGS IN THIS POST!!!
FINAL DRAWINGS ARE LOCATED IN POST #62!
Build thread photos, steps and methods are accurate and should be followed.
Got a late start today… I’ve become so excited about this project that I began to see Tresa and Kyla pick up “my slack” around here, so I put in some time… Bless them! They TOTALLY support what I’m trying to do by getting the model aircraft side of my business “off the ground”… No complaints, no “looks” just smiles and kisses and hubs… Geeze! How could I NOT stop what I’m doing to love them back!
So I finally got started around 11 this morning and just as I was getting ready to follow the drawings I created earlier this morning I saw major changes looming over the horizon!
As I sat in the shop laying out the wing panels I noticed an old AP prototype I created for a client hanging from the ceiling… The target for that project: SUPER SLOW flight… as in: “Walking Speed”… Fortunately I always write down the specs on a prototype so I can compare changes… Pulled it down and began to go over it’s “numbers/specs”
My first “guesstimate” for the EyePlane was 30” and 184.4 sq/in.
After reconsidering, I upped it to a 40” span (I can always cut it down later after test flights if I want… Making it longer now will make changing it to smaller, easier later on down the road.) At 40”, I wound up with 221.25 sq/in.
I usually work with large items or do the messy cutting, sanding, grinding, machining or other wise loud dusty processes in the “shop”… The “studio” is up front and what I normally call my “clean room”… Sometimes I will sand in there just because I like the studio more in the winter. Because I was laying out larger pieces, I chose to begin working in the shop.
Something else that slowed m down today was that I totally forgot about documenting EVERYTHING I do! If not, how do I relate the info to you and/or how do I figure out where I might have gone wrong and back track to find a new solution to some now unseen problem? (That’s a MAJOR difference between ‘recreational” building and building a prototype to be duplicated later.) So, I didn’t accomplish as much as I wanted today, but the drawings for the “final” design are done, my wing panels are cut, my materials are gathered and ready, I’ve figured out how I’m going to create this wing and (as you’ll see in the next post, I actually got quite a bit of sanding/shaping completed!
It’s about 6pm and I’m going to call it a day after I post this and the next installment… In retrospect, I think I got a lot done: Committed to a wing panel and design, documented everything, photo-documented the build (Oh… here’s some advice… it is TOTALLY WORTH IT to purchase a rubber cutting mat… You can find them at craft and art stores… they will help produce the cleanest cuts you ever saw…! And save your blades… but… NEVER use CA on them… Pull the mat away and work on a different surface (or have a separate table to cut wood and foam)…
As for the “dime tour” of the shop: The two vacuum formers seen in the shop are 24” x 24” and 18” x 30”. Major heavy duty graphite rotary vane pumps in both pulling 27hg at 11 cubic feet a minute. Here’s a short video showing one of them producing parts for my ICON kits: (And yes, I designed and built all three machines! lol!)
There’s still one more room with a third, 24” x 48” vacuum former, but I have a client project going on in there and photographs would violate confidentiality… sorry…
As for the lines and beveling of these flat wing panels: The point is to create a wing with some camber and washout… The camber is what gives a wing lift… Rounded top, flat or under-cambered bottom with a sharp trailing edge and a gentle climb up and over the leading edge to help prevent airflow breaking away and creating turbulence and deteriorating lift…
Sanding the top of the root in the outer panel and feathering it out toward the tip where none of the top of the wing is sanded, helps create the washout… On the bottom, we do just the opposite… We sand the bottom trailing edge near the tip and feather it towards the root where we sand none of the bottom of the wing… When it’s completed and you look at the trailing edge from behind, there should be a “twist” of the trailing edge beginning at the bottom near the root and then climbing up towards the top of the wing at the tip.
What Washout does is to change the angle of attack of the wing from the root towards the tip… Generally in a stall, the wing is at a high angle of attack and the airflow is “stalled” deteriorating lift… If this happens at the tip where our ailerons are, the tip falls out of the sky like a lead balloon… Usually this happens on approach and take off especially if we bank into a tight turn or just try to climb too steeply… Washout decreases the angle of attack of the tip so that the root stalls first leaving us with some aileron authority at the tip which we will hopefully take advantage of to keep flying! LOL!
(Please note: The topic of theoretical aerodynamics can be a great discussion and pastime, especially over a few beers… I only offer this limited amount of information to give those of you who have not delved into this science, a minimal understanding… I just don’t have the time to address questions or engage in discussions about it here… I believe there is a forum just for that very purpose… I still study books and read papers on aerodynamics and new airfoils that are constantly being created… There are thousands of them! Great focus for those of you interested in designing your own planes (especially sailplanes!)
Ok. From here we go into the studio to sand these wing panels to shape.
Please note that the drawings posted here are only for conceptual understanding of what and why we are going to sand these panels… More in the next post.