Kiteforum.com

Very interesting about the Tip washout guys. I can measure my Moses again and post pictures of how i am measuring. It may me my method.

I am also curious about what profile to use. DevCad Wind Mold has Eppler 817, 818 etc. But i have read that a T. Speer 105 foil would be better.
http://www.tspeer.com/Hydrofoils/h105/h105.htm
Those are not in the program, but you can go into each profile and make changes to the numbers.

I have been modeling on SolidWorks and this gives me a high degree of control on the wing design and details of mold. BUT i have to draw the foils by drawing splines over uploaded images of the foil profiles that are very low resolution.

Kosta- It seems difficult with DevCad- I will not be able to split the mold into parts because it makes mold in one big part in STL. Is this correct ?

I just looked at SolidWorks, and it says i can import a STL file as a solid part. That would allow me to import a wing from DevCad Wind Mold into SolidWorks and do the mold design as i wish in parts small enough for my 3D printer.

Kosta- would you send me a test wing in STL from DevCad so i can test this method ? I promise i will not make a wing or distribute the file. You can PM me.

In the stl tools menu there is a tab for splitting stl files. Without license cannot test but I think this is what we need. If not tinkercad can edit the big stl and make smaller piece.

You do not really need to trace splines over airfoil images. Almost all CAD tools can import a list of coordinates into a spline, and do does SolidWorks. Check this video out [youtube]https://www.youtube.com/watch?v=aT9z-D_dwU4[/youtube]

You can find h105.dat file online, and draw a wing in a matter of minutes.

I am thinking of starting with a back wing like this one : I made the leading edge deliberately straight, with no sweep. I will be able to laminate this with glass just by folding saturated cloth over it. I will also try printing a thick lower aspect stabilizer out of PETG material and see if it holds. If it fails at layer bonds I will rotate it and print again so its stronger.

If I this turns out OK, I will move on to printing a front wing.

Greetungs

Tom Speer was so kind to send me the DAT of his profile last year. There is a function in devmold where you can import DAT files either for short use or to import it in the database. In any case do not copy/paste the code from here directly into the programm. Should you catch a piece HTML like <br> which is not vissible, the programm will fail importing. You need to import into a coding editor first and save it as dat. I highly recommend https://notepad-plus-plus.org/ for this. It is freeware The editor you have on your windows is junk. Copy/paste everything exluding -----snip------

-----snip------

H105
1.00000 .00000
.99645 .00088
.98649 .00353
.97108 .00762
.95055 .01271
.92523 .01867
.89558 .02530
.86207 .03236
.82513 .03957
.78520 .04667
.74269 .05340
.69802 .05955
.65161 .06492
.60385 .06934
.55516 .07270
.50595 .07493
.45662 .07600
.40763 .07595
.35946 .07484
.31258 .07272
.26751 .06966
.22470 .06570
.18461 .06093
.14765 .05540
.11420 .04920
.08459 .04242
.05908 .03517
.03791 .02760
.02125 .01989
.00927 .01229
.00212 .00513
.00061 .00245
.00011 .00093
.00003 -.00044
.00044 -.00175
.00129 -.00313
.00475 -.00659
.01491 -.01268
.03019 -.01888
.05029 -.02499
.07490 -.03081
.10373 -.03617
.13648 -.04089
.17285 -.04482
.21249 -.04786
.25505 -.04992
.30015 -.05094
.34738 -.05091
.39633 -.04982
.44656 -.04773
.49761 -.04470
.54900 -.04084
.60026 -.03628
.65088 -.03119
.70036 -.02578
.74816 -.02025
.79374 -.01486
.83655 -.00987
.87598 -.00559
.91136 -.00227
.94190 -.00017
.96670 .00071
.98498 .00070
.99621 .00025
1.00000 .00000

-----snip------

TomW wrote: ↑

Mon Jan 08, 2018 8:54 pm

Very interesting about the Tip washout guys. I can measure my Moses again and post pictures of how i am measuring. It may me my method.

I am also curious about what profile to use. DevCad Wind Mold has Eppler 817, 818 etc. But i have read that a T. Speer 105 foil would be better.
http://www.tspeer.com/Hydrofoils/h105/h105.htm
Those are not in the program, but you can go into each profile and make changes to the numbers.

I have been modeling on SolidWorks and this gives me a high degree of control on the wing design and details of mold. BUT i have to draw the foils by drawing splines over uploaded images of the foil profiles that are very low resolution.

Kosta- It seems difficult with DevCad- I will not be able to split the mold into parts because it makes mold in one big part in STL. Is this correct ?

It is like the windego says, in the STL tools is a funtion where you can split the mold.

tks

Kosta

Thanks a lot guys. learning tons from you.

My plan is to:
1. model the wing - probably in Solid works first
2. print out mold parts in my small FDM printer
3. glue mold parts together onto wood plate
4. finish mold surfaces with some filler and sanding
5. Cut laminates using Kosta´s template and poormans pre-peg method
6. vacuum bag entire mold in a bag.
7. repeat for other half
8. glue halves together with epoxy while in molds
9. demold.

Hi guys,

I imported that 105 profile and started modeling in SolidWorks.
I'm wondering if you modify the profil att the tip. It seems really thick there compared to my Moses if I just scale it to fit my cord at the tip. I'm scaling in both Axis.

TomW wrote: ↑

Tue Jan 09, 2018 6:21 pm

Hi guys,

I imported that 105 profile and started modeling in SolidWorks.
I'm wondering if you modify the profil att the tip. It seems really thick there compared to my Moses if I just scale it to fit my cord at the tip. I'm scaling in both Axis.

I would not use it. You have to look for profiles that can handle low Reynold Numbers.

tks

Kosta

Kosta, you would not use the H105 profile?
Thought it was good for low Reynolds numbers...