Page 3 of 8 FirstFirst 1 2 3 4 5 6 7 ... LastLast
Results 15 to 21 of 51
  1. #15
    Quote Originally Posted by Wing 11 View Post
    What is faster matt or polish bottom?
    I can see it making a very minutely insignificant difference in displacement, but when a windsurf is planing it is almost constantly in a turbulent regimen ... in those conditions micron size differences in texture might matter even less ...
    Last edited by duzzi; 17th April 2018 at 06:50 PM.

  2. #16
    Senior Member chrispavlo's Avatar
    Join Date
    Feb 2009
    Location
    Austria
    Posts
    5,847
    some experiences I made when painting the bottom with Veneziano yacht paints:

    Quote Originally Posted by chrispavlo View Post
    my first experience was with the pictured board - it was fresh and shiny painted
    and i had a short evening session when i arrived in croatia.
    i felt that something was wrong and the board didn't get free as usual -
    thought is was the sailtrim with a new mast that i also tested.
    then later in the evening for some reason i did some bottom sanding
    and next day the board accellerated superfast with the same sail trim.

    on another day i tried both my *acid77 and my proof waveline75 on lake neusiedl -
    both boards were nicely painted at the bottom and both felt unusual 'sticky' and slow.
    i remembered my experience with the other board described above
    and quickly dry sanded the bottom of both boards - and both were fast again.
    this was within 1 hour and with exactly the same sail trimm and in constant winds.

    the right side on the picture was sanded (=left side of the board).
    the pic shows that there are waterdrops on the left (shiny painted) side
    while there's a smooth waterfilm on the right (sanded) side.
    the latter bottom finish definitely planed earlier and felt faster.
    don't ask me why - maybe the rougher surface is less 'sucky' to the water.
    it also applies to the dedicated veneziano painting and others may be different!

  3. #17
    Senior Member mark62's Avatar
    Join Date
    Oct 2004
    Location
    West Kirby
    Posts
    384
    Quote Originally Posted by Wing 11 View Post
    This is official information,where you find this information?
    Remi Vila told me this

  4. #18
    Senior Member
    Join Date
    Nov 2009
    Posts
    3,876
    I suspect the large vortex coming off each side of the hull if it is a glossy smooth finish serve to suck the board down onto the water. The vortex coming off an aircraft wing produces turbulence but also low pressure. Similarly on a fin with a gloss finish the vortex off the trailing edge would both create drag and encourage cavitation. Sanded is the way to go!!

  5. #19
    Senior Member chrispavlo's Avatar
    Join Date
    Feb 2009
    Location
    Austria
    Posts
    5,847
    Quote Originally Posted by mikerb View Post
    Sanded is the way to go!!
    goes conform with my experience, while I got very good results with 80-100 grit dry sanded

  6. #20
    Senior Member Radialhead's Avatar
    Join Date
    Sep 2012
    Location
    Wiltshire
    Posts
    709
    I remember reading something about this on Eva's site (Boardlady). She's taken the site down, but it's still on WayBackMachine. https://web.archive.org/web/20171012...om:80/fast.htm

  7. #21
    Senior Member Navegante's Avatar
    Join Date
    Dec 2010
    Location
    40 48'N 14 26'E -Western Med - West South Atlantic
    Posts
    2,953
    Quote Originally Posted by chrispavlo View Post
    goes conform with my experience, while I got very good results with 80-100 grit dry sanded
    Sun of a gun!!!!
    Murder!!!!!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •