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Brandonh291 / RC-Plane

This will be a full step-by-step production through all stages using systems engineering approach.
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Wing Design #11

Closed Brandonh291 closed 12 months ago

Brandonh291 commented 1 year ago

Trying to get the wing design finished, will be doing prototyping to determine feasibility for a alternating rear and forward spar pattern, no carbon rod.

Brandonh291 commented 1 year ago

Currently testing new wing design.

Brandonh291 commented 1 year ago

So far, printed most of the wing and I will need to make the following revisions.

  1. Make the spaces between the spars larger. Right now its either a 2mm or 3mm space, which makes a space that can bend easily and break faster. While I don't think its going to be a major issue since the spares should keep it from bending around that point, likely a failure point nonetheless.

  2. It might be lower weight to use only half the spars and use a carbon fiber rod. The issue with the rods is that I need to use atleast 3 rods give they are about 14-16 inches long and the wingspan is 40 inches. This means I need to either bond rods together in a way that wont become a point of breakage, or use twice the rods in an alternating fashion like I am doing with the spars. I will check the weight of the wing after I have completed all the spars and compare that with a few options: 4 spars & no rods, 2 spars and 1 Rod, and 2 Spars with 2 rods. I need the spars to get the spacing for the wing ribs and I think I plane to use the spars as a way to mount my aileron control servos. Though, in previous designs , I was able to mount a servo using two rods instead, but that became an issue with printing and keeping it in place.

  3. Adjustments to aileron print need to be made. Most of the piece is good, but the printer is struggling to keep the holes for the rotation points of the aileron from collapsing. I will look at tuning the printer, and maybe adjusting print orientation.

  4. I still need to figure out the leading and trailing edge. My current idea is to use a slightly thicker tape or material like paper or painters tape or duct tape to use one long piece along the trailing and leading edge. This gives a unified form for each part and would give more material for my skin to connect to.

  5. I also need to adjust the end spars and end rib to become something like an end cap. The sharp cut-off probably does not create a huge effect at this low of speed. However, I believe the end cap will provide a better connection on the last spar, and I can use it as a larger skin space for attaching the skin. Plus it technically could be a nice bevel off to also house any excess rods I might use, and wingtip vortices.

Brandonh291 commented 1 year ago

Wing design, the alternating spars do not provide the needed strength. Just holding one end of the wing on the table and letting the rest hang over the edge causes a drop of 400 mm or a bend of 25 degrees under its own weight. So I am going to look at just doing carbon fiber rods instead with a alternating set and use the spars as only a single set rear and front being offset from each other to keep spacing correct. I honestly might trim off the edge of the airfoil trailing edge because it is a pain to print and I might be able to add a trail edge piece with the weight saved from removing the spars.

Brandonh291 commented 1 year ago

I am going to make a new wing file and attempt to start semi-scratch to change to a two-spar/2 rod system and keep this 4 rod version up as a separate version just so its not overwritten.

Brandonh291 commented 1 year ago

I also plan to still test the endcap and spar hook because I can end the rods inside the end cap and its good end joiner piece for the spars that remain.