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Re: More wings, the hard way?

Posted: Wed Feb 21, 2018 5:57 pm
by tahoedirk
Ya the angle of the photo is off, it's actually summer out too

These are all about 10 layers of 6oz, it seems like enough. I only clamp the edges. If one of these is a hit , I'm sure I can beef up and refine the mold further.

I think the trick is to really wax the LE and TE well before glassing the second half. The sharper edges of epoxy will break off otherwise , making much more work.

Re: More wings, the hard way?

Posted: Wed Feb 21, 2018 6:50 pm
by Bille
tahoedirk wrote:
Wed Feb 21, 2018 5:57 pm
...

These are all about 10 layers of 6oz, it seems like enough. I only clamp the edges. If one of these is a hit , I'm sure I can beef up and refine the mold further.

...
A seriously inexpensive and FAST way to beef-Up that mold, is to place
a cardboard retaining wall around the edges of the mold-half ; then
put a few inches of Hydrocal-30, or Ultracal-30 inside your dam. Sand
your glass mold , with 30 or 50-grit first ; and the plaster will stick just fine.
The plaster is about $25 for a 100Lb bag.

Anything Ya don't want the plaster to stick to ; just wax it first, (even the cardboard).

If Ya want to keep the mold ; place hemp fibers , or dry fiberglass
in the plaster , to keep it from cracking.

Alignment pins , are easily set in the plaster, ; and both those materials
i mentioned, have a WAY less expansion rate, than regular plaster, when
they are hydrogenated.

First thing you will notice when making a mold from scratch , using
this system ; Ya only need one or two layers of 6-oz glass now, instead of 10.
I use (2) layers of 3-oz plain weave.

It works Great for small parts like a hydrofoil wing ; larger parts
get a bit more complicated because of different expansion rates and such
but are easily over-come.

Bille

Re: More wings, the hard way?

Posted: Sat Feb 24, 2018 5:11 pm
by Bille
tahoedirk wrote:
Mon Feb 05, 2018 8:06 pm
Wow! Not a comment, addition or anything, I'm pouring my guts out, for years, every hard won tip that I can share.. I always hope I reach at least one interested builder.


...
Times that by 3 days , for Me . :(

Re: More wings, the hard way?

Posted: Sun Mar 04, 2018 9:05 pm
by thewindego
Hi makes of foils

For the rear stabilizer wing is it reasonable to go with a similar profile as the front wing?

Re: More wings, the hard way?

Posted: Wed Mar 07, 2018 4:21 pm
by tahoedirk
Hi there,
I think it is reasonable . If the profile does not have radical camber you should be fine. Good luck!
Where is Wolfe island?

Re: More wings, the hard way?

Posted: Wed Mar 07, 2018 4:42 pm
by thewindego
Thanks Tahoe! I am in Ontario Canada...winter still.

Re: More wings, the hard way?

Posted: Tue Jul 10, 2018 7:05 pm
by bisdremis
Bille wrote:
Tue Feb 13, 2018 4:13 pm
opie wrote:
Mon Feb 12, 2018 1:38 pm
...
It reminds me of trying to figure out math problems when I was a kid. :)
Last week, the local news in Vegas, had a story about 3'd graders, being taught how
to use a 3D printer ; kinda makes me think, that even My dumb-A$$ , could
learn how to do that ? :(

Any recommendations, on where to start ? Please don't tell me 3'd grade ; or
i'll get Bummed.

http://www.lasvegasnow.com/news/3d-prin ... /962977814

Bille
i would recommend something like this , easy setup , very reliable , great final product finish, big build volume (essential for foil building) , its like a toyota of 3d printers you cant go wrong with this :https://uk.gearbest.com/3d-printers-3d- ... kIQAvD_BwE
other wise for higher budget but with less build volume you go there:https://shop.prusa3d.com/en/3d-printers ... inter.html#
with one of those tools you would have great 3d printing results

Re: More wings, the hard way?

Posted: Thu Aug 02, 2018 5:19 pm
by tahoedirk
Finally getting to ride these wings!

Yipee, after struggling with my 2 piece foil for over a year, I am back to mostly positive results.

The two similar wings I made are working very well. I have a 580 and a 800 and they are quite similar. Previously I was making 500 cm2 wings . The bigger sizes are easier to nail flying transitions by far, especially tacks and toeside tack. The 800 does not like to be overpowered and tops out around 25mph.

I am just tickled by the behavior of my new w shaped wings. When the wingtip pokes through the surface of the water ...... nothing happens, just a small slurping sound... no crash, no explosion. What a treat .
I haven't put the double w (cormorant) wing through its paces quite yet.


There is almost nothing I can think of to change..... almost... After measuring, these wings came out at 13% thickness, I was shooting for 10%. I really want to try the same wing at 8 or 9% thickness now.

Tuning is the challenge. Any time I change one thing, I have to change something else to compensate. Perfect AOA of front and rear , wing pairing and foot placement are extremely elusive.

If you have a full time job or career , maybe just buy a nice used foil that works well. That will leave a lot more time for hydrofoiling!