Contact   Imprint   Advertising   Guidelines

sanding mast & foils - which grit to use

A forum dedicated to Hydrofoil riders
User avatar
mede
Very Frequent Poster
Posts: 512
Joined: Fri May 24, 2002 1:00 am
Kiting since: 2001
Weight: 72 kg dry
Local Beach: Sri Lanka West Coast
Favorite Beaches: Sri Lanka West Coast, Cape Verde, Tarifa, Beauduc, Corpus Christi
Style: Strapless surfing, Big Air
Gear: Tomo Vader 5.1 HE, Gong Curve & Fluid, Kauper Falcon 11m, Blade Trigger 5m & 8m & 10m, Storm Voyager 13m
Brand Affiliation: none
Location: Sri Lanka / Switzerland
Has thanked: 62 times
Been thanked: 20 times

sanding mast & foils - which grit to use

Postby mede » Mon Mar 07, 2022 8:25 am

Hey everyone

I would like to sand my mast and foils, in order to avoid ventilation and increase speed.
Did my online research, but did not find consensus on what is the best grit to use at what places on the foil and mast.

Older posts seem to favor 1000 - 2000 p, newer ones rather 400 - 800 p.

Recommendations? I'm also interested in the reasoning behind those.

Many thanks in advance,
Mathias
Last edited by mede on Mon Mar 07, 2022 6:03 pm, edited 1 time in total.

evan
Very Frequent Poster
Posts: 919
Joined: Sat Jan 31, 2004 5:48 pm
Kiting since: 2002
Local Beach: Brouwersdam
Style: Hydrofoil - Big Air
Gear: Infexion bars
Brand Affiliation: Infexion
Has thanked: 10 times
Been thanked: 226 times
Contact:

Re: sanding mast & foils - which grit to use

Postby evan » Mon Mar 07, 2022 9:19 am

LE > TE
Submerged surfaces 2000 - 1200 - 800
Breaching surfaces 800 -1200 - 2000 (top mast, wingtips)
all cross sanded 45deg and use a spraypaint base coat before sanding to fill any imperfections.

Big plans for trying to reach cavitation speeds of 55kn+ ( or did you mean ventilation?)
These users thanked the author evan for the post:
mede (Mon Mar 07, 2022 6:03 pm)
Rating: 6.67%

Oldman
Rare Poster
Posts: 43
Joined: Mon Jun 02, 2014 4:35 pm
Kiting since: 2009
Gear: . Foil, surfboard
Brand Affiliation: None
Has thanked: 61 times
Been thanked: 4 times

Re: sanding mast & foils - which grit to use

Postby Oldman » Mon Mar 07, 2022 11:02 am

evan wrote:
Mon Mar 07, 2022 9:19 am
LE > TE
Submerged surfaces 2000 - 1200 - 800
Breaching surfaces 800 -1200 - 2000 (top mast, wingtips)
all cross sanded 45deg and use a spraypaint base coat before sanding to fill any imperfections.

Big plans for trying to reach cavitation speeds of 55kn+ ( or did you mean ventilation?)
Can you explain what you mean by '2000-1200-800'?
Thanks

evan
Very Frequent Poster
Posts: 919
Joined: Sat Jan 31, 2004 5:48 pm
Kiting since: 2002
Local Beach: Brouwersdam
Style: Hydrofoil - Big Air
Gear: Infexion bars
Brand Affiliation: Infexion
Has thanked: 10 times
Been thanked: 226 times
Contact:

Re: sanding mast & foils - which grit to use

Postby evan » Mon Mar 07, 2022 11:24 am

LE of the profile 2000 grit, middle 1200, TE 800 for least drag.

The reverse for least ventilation on the surface piercing profiles, some even do a single perpendicular pass with even coarser grit just on the first cm of the LE to reduce the ventilation even further.
These users thanked the author evan for the post (total 3):
Oldman (Mon Mar 07, 2022 12:39 pm) • mede (Mon Mar 07, 2022 6:48 pm) • DAnderson (Mon Mar 07, 2022 7:20 pm)
Rating: 20%

User avatar
mede
Very Frequent Poster
Posts: 512
Joined: Fri May 24, 2002 1:00 am
Kiting since: 2001
Weight: 72 kg dry
Local Beach: Sri Lanka West Coast
Favorite Beaches: Sri Lanka West Coast, Cape Verde, Tarifa, Beauduc, Corpus Christi
Style: Strapless surfing, Big Air
Gear: Tomo Vader 5.1 HE, Gong Curve & Fluid, Kauper Falcon 11m, Blade Trigger 5m & 8m & 10m, Storm Voyager 13m
Brand Affiliation: none
Location: Sri Lanka / Switzerland
Has thanked: 62 times
Been thanked: 20 times

Re: sanding mast & foils - which grit to use

Postby mede » Mon Mar 07, 2022 6:04 pm

evan wrote:
Mon Mar 07, 2022 9:19 am
Big plans for trying to reach cavitation speeds of 55kn+ ( or did you mean ventilation?)
Corrected, thanks :thumb:

User avatar
mede
Very Frequent Poster
Posts: 512
Joined: Fri May 24, 2002 1:00 am
Kiting since: 2001
Weight: 72 kg dry
Local Beach: Sri Lanka West Coast
Favorite Beaches: Sri Lanka West Coast, Cape Verde, Tarifa, Beauduc, Corpus Christi
Style: Strapless surfing, Big Air
Gear: Tomo Vader 5.1 HE, Gong Curve & Fluid, Kauper Falcon 11m, Blade Trigger 5m & 8m & 10m, Storm Voyager 13m
Brand Affiliation: none
Location: Sri Lanka / Switzerland
Has thanked: 62 times
Been thanked: 20 times

Re: sanding mast & foils - which grit to use

Postby mede » Mon Mar 07, 2022 6:08 pm

evan wrote:
Mon Mar 07, 2022 9:19 am
LE > TE
Submerged surfaces 2000 - 1200 - 800
Breaching surfaces 800 -1200 - 2000 (top mast, wingtips)
all cross sanded 45deg and use a spraypaint base coat before sanding to fill any imperfections.
What is the source of your info? What is the rationale for going so fine for a start ? (on French forums, consensus seem to become to go more coarse for performance gains, finer more for looks)
Did you personally test this? If yes, with what methodology?

evan
Very Frequent Poster
Posts: 919
Joined: Sat Jan 31, 2004 5:48 pm
Kiting since: 2002
Local Beach: Brouwersdam
Style: Hydrofoil - Big Air
Gear: Infexion bars
Brand Affiliation: Infexion
Has thanked: 10 times
Been thanked: 226 times
Contact:

Re: sanding mast & foils - which grit to use

Postby evan » Mon Mar 07, 2022 6:10 pm

This is what the Levitaz and their riders are using, winning almost all the big events last year so they must be doing something right ;)

kit3surfer
Medium Poster
Posts: 83
Joined: Fri Jan 17, 2020 6:34 pm
Kiting since: 2010
Gear: North
Brand Affiliation: None
Has thanked: 0
Been thanked: 5 times

Re: sanding mast & foils - which grit to use

Postby kit3surfer » Mon Mar 07, 2022 9:30 pm

Is it possible to sand too much - will I recognize this?
Are there risks to demage the carbon layers and what happens if yes?

StellaBlu
Frequent Poster
Posts: 274
Joined: Fri Jul 31, 2020 6:19 pm
Kiting since: 2015
Style: Winging
Gear: -
Brand Affiliation: None
Has thanked: 32 times
Been thanked: 54 times

Re: sanding mast & foils - which grit to use

Postby StellaBlu » Mon Mar 07, 2022 9:41 pm

kit3surfer wrote:
Mon Mar 07, 2022 9:30 pm
Is it possible to sand too much - will I recognize this?
Are there risks to demage the carbon layers and what happens if yes?
Im not a tech, but if it starts producing dark sanding residue you have probably gone too far. I say probably because I've also seen pigmented clear coat or filler that produces similar residue (which is still probably ok to sand). Someone suggested spraying additional clear coat on top in order to fill any imperfections, which I agree with, but it also gives you a little bit more surface to sand. Keep in mind, that this kind of sanding isn't to remove material - the purpose is just to finish the surface (hence the superfine grit).

kit3surfer
Medium Poster
Posts: 83
Joined: Fri Jan 17, 2020 6:34 pm
Kiting since: 2010
Gear: North
Brand Affiliation: None
Has thanked: 0
Been thanked: 5 times

Re: sanding mast & foils - which grit to use

Postby kit3surfer » Mon Mar 07, 2022 10:00 pm

Thanks, and in case it becomes black dust, what is the consequence after stopping to sand of course. Will the carbon layer suck water and do I have to put on a kind of finish/spray afterwards or will it be also fine if I keep it like that?


Return to “Hydrofoil”

Who is online

Users browsing this forum: Google [Bot] and 2 guests