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Other: Sanding the bottom
By:Malcolm Schweizer
Date: 4/14/2011, 10:59 pm

Hello all,

I guess this is what happens when you're too tired to sleep, but I was thinking about bottom paint after responding to Bill on using graphite in the bottom coat. It got me to thinking about what I have read and practiced in both sailboat racing and in surfing- sanding the bottom to 400 grit and leaving it at that as opposed to the nice shiny finish. What it does is causes water to adhere to the hull and creates kind of a barrier layer. The water molecules that "stick" to the sanded finish actually ride along with the kayak, so your hull is now riding on little ball-bearings of water molecules which reduce the friction. Is this making sense? I didn't think so.

Well, it's been hotly debated on many forums. Think of it this way- take a nice shiny smooth hull and wet it down. Now run your hand over it. Your hand will get friction and sometimes even squeak as you slide it over the hull. squeeeeeeeeeek Now sand it to 400 grit, wet it, then do it again. Your hand will smoothly glide over the hull.

I just thought I'd throw it out here for discussion. It works! It's no big deal for recreational kayaking, and I don't want to create a great divide- sanders and non-sanders- but I would like to hear thoughts and comments.

Somewhere out there is a youtube video that shows this effect but I can't remember what it was titled.

BTW, I'm a sander, but for a pretty boat that I want to show off every inch of and don't really care how fast it goes I'm a non-sander. Call me a hypocrite.

Messages In This Thread

Other: Sanding the bottom
Malcolm Schweizer -- 4/14/2011, 10:59 pm
Re: Other: Sanding the bottom
StephenHJ -- 4/15/2011, 2:13 am
Re: Other: Sanding the bottom
Malcolm Schweizer -- 4/15/2011, 5:04 am
Re: Other: Sanding the bottom
Bill Hamm -- 4/15/2011, 6:14 am
Re: Other: Sanding the bottom
Malcolm Schweizer -- 4/15/2011, 7:24 am
Re: Other: Sanding the bottom
Bill Hamm -- 4/15/2011, 7:37 am
Re: Other: Sanding the bottom
Mike Savage -- 4/15/2011, 12:59 pm
Re: Other: Sanding the bottom
Dave Houser -- 4/15/2011, 3:13 pm
Re: Other: Sanding the bottom
Bill Hamm -- 4/17/2011, 1:16 am
Re: Other: Sanding the bottom
ancient kayaker -- 4/17/2011, 9:28 pm
Re: Other: Sanding the bottom
Robert N Pruden -- 4/18/2011, 9:01 pm