Contact   Imprint   Advertising   Guidelines

cheapo foil setup

A forum dedicated to Hydrofoil riders


longwhitecloud
Very Frequent Poster
Posts: 1907
Joined: Fri Sep 11, 2009 3:15 am
Kiting since: 0
Style: Fast, anti lawnmower.
Gear: Wipika Freeair 8.5 2 liner and Picklefork.
Brand Affiliation: iansmusic.com - free music for your kite videos

cheapo foil setup

Postby longwhitecloud » Sun Dec 01, 2013 7:51 am

about $5 for each wing (tried on other tbar - bit draggy but fine - 15mm ply) aluminum $60 welding $70 ?

didnt get a chance to ride it before it broke but friend got up on it but it slowly started to bend...

aluminium square section thickness too thin - choppin it off and adding a solid bar or greater wall thickness.

went for spin behind ski on another one - i was like a yoyo lol
2013-12-01 18.28.36.jpg

User avatar
Hawaiis
Very Frequent Poster
Posts: 1370
Joined: Wed Aug 24, 2011 11:39 am
Kiting since: 9
Local Beach: Kailua
Brand Affiliation: None

Re: cheapo foil setup

Postby Hawaiis » Sun Dec 01, 2013 8:32 am

What wall thickness is too weak?
I bought some aluminum square tubes with1/8" wall thickness.

zfennell
Very Frequent Poster
Posts: 972
Joined: Wed Nov 20, 2002 1:00 am
Kiting since: 0
Brand Affiliation: None
Location: rhode island

Re: cheapo foil setup

Postby zfennell » Sun Dec 01, 2013 7:13 pm

longwhitecloud wrote:...

aluminium square section thickness too thin - choppin it off and adding a solid bar or greater wall thickness.




or you could position the vertical strut on top of the front wing/foil while you work out other design details.

how much does your friend weigh?
that should help with sizing components for the future

User avatar
DrLightWind
Very Frequent Poster
Posts: 1806
Joined: Mon Aug 12, 2002 1:00 am
Kiting since: 2001
Local Beach: Matheson Hammock Park Miami
Favorite Beaches: Crandon Beach, Hobbie Beach, Keys, St. Lucia, St. Marteen,
Style: Old School
Gear: Flysurfer15m and 21m Speed3 DLX
RealWind Mutant 148 X 40 and Directional 190 X 48, F-One TT 128 X35, Dereck Semi Directional 143 X 38 and 177 X 46.
Brand Affiliation: None
Location: Miami @ 6" Flat Butter!

Re: cheapo foil setup

Postby DrLightWind » Sun Dec 01, 2013 9:26 pm

Nice set-up :thumb:
But isn't the front foil has Excessive Angle Of Attack :?:

DrLW
Attachments
Angle Of Attack.jpg
Angle Of Attack.jpg (29.78 KiB) Viewed 1116 times

User avatar
Peter_Frank
Very Frequent Poster
Posts: 7070
Joined: Wed Oct 16, 2002 1:00 am
Kiting since: 0
Brand Affiliation: None
Location: Denmark

Re: cheapo foil setup

Postby Peter_Frank » Sun Dec 01, 2013 10:25 pm

No, the picture is (must be) taken AFTER it broke/bent :wink:

8) Peter

User avatar
DrLightWind
Very Frequent Poster
Posts: 1806
Joined: Mon Aug 12, 2002 1:00 am
Kiting since: 2001
Local Beach: Matheson Hammock Park Miami
Favorite Beaches: Crandon Beach, Hobbie Beach, Keys, St. Lucia, St. Marteen,
Style: Old School
Gear: Flysurfer15m and 21m Speed3 DLX
RealWind Mutant 148 X 40 and Directional 190 X 48, F-One TT 128 X35, Dereck Semi Directional 143 X 38 and 177 X 46.
Brand Affiliation: None
Location: Miami @ 6" Flat Butter!

Re: cheapo foil setup

Postby DrLightWind » Sun Dec 01, 2013 11:07 pm

Peter_Frank wrote:No, the picture is (must be) taken AFTER it broke/bent :wink:

8) Peter
You right, I didn't realize it was after :thumb:

longwhitecloud
Very Frequent Poster
Posts: 1907
Joined: Fri Sep 11, 2009 3:15 am
Kiting since: 0
Style: Fast, anti lawnmower.
Gear: Wipika Freeair 8.5 2 liner and Picklefork.
Brand Affiliation: iansmusic.com - free music for your kite videos

Re: cheapo foil setup

Postby longwhitecloud » Mon Dec 02, 2013 1:51 am

gave it a good shot at this aoa anyway lol - fail...

gotta check wall thickness still will do then off to aluminium welders again

don pitcher
Frequent Poster
Posts: 210
Joined: Sat Aug 27, 2005 7:32 am

Re: cheapo foil setup

Postby don pitcher » Mon Dec 02, 2013 2:00 am

Not bad for your first prototype! Your next prototype will be much better. Here is what I think will help.

The heat from welding has annealed (weakened) the aluminum. With aluminum, this is a big change in the strength of the material.

If welding aluminum and not heat treating afterword, 5086 is nicer than 6061 because it has a much higher annealed strength.

6061-T6, 40,000 psi yield stress

6061-O annealed, 8,000 psi yield stress

5086-O annealed, 17,000 psi yield stress

From this you can see that:
* it is best to have aluminum heat treated after weld so it can be strengthened (added cost)
* or design around annealed aluminum
* or find another way to attached rather than welding

Also, I believe the aluminum from HomeDepot is 6063-T5 (21,000 psi yield stress) that is annealed to 7,000 psi yield stress at the heat affected zone of the weld.

www.matweb.com is a nice reference for material strength, but your material supplier should be the best reference.

I think if you found a way to bolt the fuselage on, it would work as you intended. Also, if you want to continue using the square tube in stead of a square solid, it might be worth getting 6061-T6.

I hope this helps.

longwhitecloud
Very Frequent Poster
Posts: 1907
Joined: Fri Sep 11, 2009 3:15 am
Kiting since: 0
Style: Fast, anti lawnmower.
Gear: Wipika Freeair 8.5 2 liner and Picklefork.
Brand Affiliation: iansmusic.com - free music for your kite videos

Re: cheapo foil setup

Postby longwhitecloud » Mon Dec 02, 2013 2:43 am

thx

longwhitecloud
Very Frequent Poster
Posts: 1907
Joined: Fri Sep 11, 2009 3:15 am
Kiting since: 0
Style: Fast, anti lawnmower.
Gear: Wipika Freeair 8.5 2 liner and Picklefork.
Brand Affiliation: iansmusic.com - free music for your kite videos

Re: cheapo foil setup

Postby longwhitecloud » Mon Dec 02, 2013 11:00 am

was pretty thin 2.5mm? got some 3.5 4mm? or try solid would be super strong but dont really want to buy this... expensive

gonna maybe lay down some carbon uni on strut and upright and wrap it up with glass round and round like hockey tape - make it nice n easy. i hate epoxy but might actually have to touch some , well with gloves anyway...

might add some super sized aluminium fillets at top to reduce torque too if welder doesnt decide to create a huuuge invoice..

really concentrating on cost - 2k on a foil inc postage to nz is ridiculous to me


Return to “Hydrofoil”

Who is online

Users browsing this forum: No registered users and 5 guests