Eppler 817 Main Foil Prototype

EFOIL.builders Foils & Boards
1

Hi All,

I’m not officially starting a build yet but as I’m wanting to try out a new vacuum bagging technique on another project, I decided to try the new idea out on a main foil. I have based the dimensions of the foil on those proposed in the "Optimum wing " thread. I have uploaded a full set of .STL’s and also the Fusion 360 file to Thingiverse so that others can modify the model. My plan is to vacuum bag the PLA printed core with a few layers of CF. As I state in my Thingiverse text, this wing is completely untested

Eppler%20817%20Foil%20v7
Eppler%20817%20Foil%20v71536×710 183 KB

My vacuum bagging will be fairly conventional except that I will be using an 0.2mm silicone film mounted in a frame as the vacuum bag. I’m confident this will mean I can skip the peel ply and most of the synthetic wadding used in most vacuum bagging setups. The silicone should stretch and most importantly, not stick to the epoxy. The foil will be my guinea pig as it’s relatively small and simple in shape.

I will keep you updated on my progress in this thread.

BTW, I am located in NSW Australia for those of you who are curious. :upside_down_face:

7 Likes
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Benonymous,

Very very nice. What about a nice rectangle hole in the middle piece to allow for some flat metal piece to insert for much stronger screws ?

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Love it! Looking to 3d Print my whole Foil on a Micromake C1 in Pla and then Fibreglass it for strenght! Keep us updated!

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Hi philgib, yes, for an insert. I could just make an updated center section for that. As it stands, I was going to through-bolt it but a plate with threads would mean only one set of draggy bolt heads :slight_smile:

1 Like
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Yes. We just did the same, printing MaB foil and cover it with carbon, but without prior inserting a strong metal central piece before covering with Carbon, and it looks to me as a mistake.

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I have added a new centre section with a recess for a 5mm thick metal plate that can be drilled and tapped for mounting the wing.

3 Likes
7

Have you tested this printed front wing yet? I´m also looking into 3d-print my own front wings but I´m looking for information about what airfoil that would suite the e-foil. Why did you decide to go with the Eppler 817?

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The Eppler 817 is a very good choice in my mind for the 2 main reasons:

  1. Thick enough so easy to manufacture
  2. Cl/Cd ratio of 80 at AOA=0 and Re number of ~1,000,000. this means that it gives much more lift relative to the drag it generates.

data for this airfoil can be found at: Airfoil comparison

The size of the wing should be adjusted for the required lift at the designed take off speed.

3 Likes
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Hello, how you think, which rear wing we need for good work with your front wing, and which dastance should be between them ?

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Hi DimaVeter,
Sorry for the very late response. I don’t have a rear wing yet or any further design details. I just wanted to create this front element to experiment with.

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Hello,

any Progress regarding the rear wing? I am very interested in your design, did you lay out the front wing yet?

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Hi very successful congratulations.
Any progress on the rear wing?
Is there an iqfoil design?