This is something I made for fun and thought I'd share. It is a fairly scale version of the old Aquila sailplane that has been around for ages. I had one way back in the early 80's and loved it. The fuse profile is very close and the airfoil is the original Aquila shape with just a little thickness added.
The size is based on a 400mm wing span. It's a two piece wing. 200mm is a big as I can print on my Ender 3. I ended up printing this at a layer height of .08mm with only one layer on the bottom of all of the pieces, 3 walls and 3 top layers. My ender 3 could handle the .08 so I don't think that it should be too difficult for most people. If not, print as thin as you can. Print the infill as a grid at about 15%. The infill should end up looking like crossing ribs set at 45 degrees to the length of the wing. If you print a line infill that looks like ribs that are perpendicular to the length of the wing it makes the wing weak and want to buckle when you give it a little bend.
It does fly although not the greatest. Small planes like this are a challenge to make fly very well. I filled the cavity in the nose with lead shot and put a piece of tape over it. I think filling it with something like epoxy and/or using clay to smooth the hole would also work well. I printed in PLA. My real reason for even starting this was to see if something like this cold be done in PLA and still be strong enough to fly. That is not a problem. I can hit the ground pretty hard and still not break.
I did all of the assembly with slow cure CA. First glue the wing halves to the fuse halves. That way you can press down on both the wing and the fuse against a flat surface and get good alignment. Then glue the two halves together with CA using the two holes in the wing roots as alignment aids. The holes are sized for the 1.75mm pla. They are each 10mm deep so cut a few pieces of PLA just under 20mm for the alignment pins. Then glue the stabilizer in. Balance is about mid wing. The rudder and stab are both "grooved" so they can be bent to help in controlling the glide. After assembly, I put a bow in the wing to help stabilize flight by simply bowing up the wings a few inches and taping them in place and let set for 24 hours. When you take the tape off, there is a nice enough set that takes place to give a smooth curve to the wings.
Like I said, it isn't the greatest flyer but I like the way it looks. My plan is to find a big cliff and toss one or two off just to see how the fly with a lot of air to stabilize out. There are two wing sets. One is a tapered wing with the correct root dimensions and tapered to look nice. The other wing is more to the original Aquila wing dimensions that is made up of two panels. That would be the "Standard" wing.
This was kind of fun. I think my next project will be a Hobie Hawk....