The preview of finished fin
A single perimeter print has gone well.
This finFoil version has a minimum thickness of 0.6mm, so that the 2 PLA layers at the trailing edge fuse.
http://finfoil.io/s/3D/as8d11qtnk8s1xxx5pki6badfmy6i8oc
I’m not sure a single perimeter print is the way to go, there might be too many resin leaks when I get around to fill the shell with epoxy.
Blind testing with accurate control of parameters - finFoil makes it possible.
That’s if I manage to print these babies tough enough so they do not snap off any longer.
The screenshot shows two finFoil programs running simultaneously in Ubuntu. I don’t know if this would be possible in a Windows OS, I had even more finFoil.exe running (using WINE) simultaneously before, it can be useful at times.
The finFoil on the left shows how I use the picture import function to fine-tune the file without bumpy leading edge foil (BLEF): I take a screen shot of the foil in the program on the right, overlay it exactly into the finFoil program on the left, then carefully adjust everything until the fins are as good as identical, except for the BLEF and 0.0081 degree difference in rake.
Below are the files which I would like to try out in high resolution, when you have time Hans.
The 0.8mm minimum thickness files are for single perimeter printing and the 1.3mm minimum thickness files are for 2+ external perimeter printing.
No BLEF with 0.8mm and 1.3mm minimum thickness files:
http://finfoil.io/s/3D/1so4skai5i6bi1x5toz86bgoydfutskx
http://finfoil.io/s/3D/g3q3jotoupkxc6oxmk3nuoiw9cof7pgw
BLEF with 0.8mm and 1.3mm minimum thickness files:
Hi Mik,
I created high resolution exports of your fins.
You can download them on the original links.
http://finfoil.io/s/3D/1so4skai5i6bi1x5toz86bgoydfutskx
http://finfoil.io/s/3D/g3q3jotoupkxc6oxmk3nuoiw9cof7pgw
http://finfoil.io/s/3D/op6ws8y5dk98wcebgnp6qrpnd8jpnmih
http://finfoil.io/s/3D/mz45guzq6u1dg3bwesqy3ucggest7baq
Keep us posted with new pics!
Regards,
Hans
Thank you very much, Hans!
I have inserted SS rods and filled a few fin shells with epoxy resin. Somewhat messy so far, the resin leaks out of the ‘internal stabilisers’ a little.
The 1.3mm minimum thickness version is probably much better than 0.8mm.
Photo shows fin shells ready for resin filling.
Hi all
I’m enjoying playing with finfoil… but I want to make a step forward.
I would like to know how to check how the water would flow throught the foil.
Any easy software for newbies like me?
Regards,
Paco
Can the profile view be adjusted so it shows the actual foil section in it’s real proportions?
The thickness of the profile appears very exaggerated and I cannot figure out how to change that.
Screenshots show finFoil screen and a fin foil profile from Airfoil database search
MrMik-
I want to say that the max camber thickness is controlled by the box on the screen.
You should be able to ‘drag’ the foil image into the profile window, move the blue trailing edge control point out to the end, the middle blue point to max camber, and play with the red control points to adjust the curve.
Pics below are those steps performed to the default fin that loads with finFoil. The thickness did not change with the move in the profile curves.
Thanks, jrandy, I should have tried that ages ago. It works just like with the outline picture import, of course.
What throws me is that the fins still come out OK when the profile shows the default hyper-thick profile.
I like the look of my profile better than the Eppler 168 profile. It may be a complete dog, of course…
But just to illustrate how similar the foils are that finFoil produces when the screen looks so very different.
Slic3r comparison of the Wanderfalke2 fin with my ‘free-hand’ profile and the same fin with Eppler 168 profile. Once above each other, once beside each other.
The other two screenshots show how different it looks in finFoil before producing near identical fins.
Link to the fin with ‘my’ foil profile: http://finfoil.io/s/3D/g3q3jotoupkxc6oxmk3nuoiw9cof7pgw
Link to the fin with Eppler 168 foil profile: http://finfoil.io/s/3D/wpucakicc19qqrzag5jtqi4ingngwdjr
Thx @jrondy for the great explanation of how to use the profile designer.
@MrMik
The reason your profile looks good when exporting is that the profile get’s stretched to match your input parameters.
First, the thickness numer will be used to identify the thickness at the thickest point.
Secondly, the outline and thicknes profile will be used to identify the thickness vs length ratio (aka. aspect ratio) of the profile at every slice
And lastly the profile will be stretched to match the required aspect ratio.
If finfoil would keep the profile’s aspect ratio constant, the fin would be overdetermined: https://en.wikipedia.org/wiki/Overdetermined_system
I had a different approach to finfoil and 3d printing… Because of I was not so sure about which materials to use for fins (I thought about PC and POM but i had no time to test these filament), I opted for printing a windsurf fin mold in PLA for my brother, 80 grams of resin and a lot of fiberglass scraps I had around and i have my first fin… I need simply to sand it a little bit and hotcoat it and it will be ready… just one small bubble to fix in the base but I’m pretty satisfied…
Looks great!
How did you make the groove for the seal and what is the seal made of?
What release agent did you use in the PLA mould?
I had at home an 1 mm elastic band used by fisherman for … I have no idea what it is used for, I’m not a fisherman… but I bought it for 1 .5 euro 5 meters , the groove is 0.3 mm depth, so 0.3mm per side 0.4 remain between the 2 mold and when screwed it was perfect… I fixed it in the groove with small little drops of cyanoacrylate.
For making the grove I designed the section on cad, then I use sweep comand along the line and a bolean difference.
For release agent I used wood wax.
What CAD program? I have only used OpenScad, no Sweep command there, it would be tricky to make a groove like that in OpenScad.
I’m using Moi3d.
Wavegrinder adaptation with leading edge tubercles:
http://finfoil.io/s/3D/4p1bn9k7igbxipo4khn4yc5jpdn9fh7f
I hope I can adapt it to my ‘Universal tough fin base’ without too much trouble.
Hans, could you please make a high resolution rendering of this file?
And check if there is something wrong with your PayPal system, I tried twice to send you another small donation but it keeps failing, I’m not sure why. I cannot find a problem on my PayPal end.
Thanks Mik I received one donation from you today.
I will create a high res version of the fin, no problem.
Thanks Hans!
The donating bit worked when I tried a third time later on, without doing anything differently.
Thanks for the donation!
For the high resolution version refresh the page!
http://finfoil.io/s/3D/4p1bn9k7igbxipo4khn4yc5jpdn9fh7f