So I'm re-doing the paint on my squarenose that I would like to perform well on a buoy course. I was wondering if anyone had opinions on whether or not to pain the bottom of the ski? I'm wondering this because I have heard that a glossy bottom deck will not handle as well as it should.. It seems like it would be retarded of me if I decided to paint it nicely and right when it dries, turn around take sand paper to it to "true" it from front to back. Anyone want to give me input on some race secrets? If I don't paint the bottom, I will paint the sides of the bottom deck of course. The giant gouges from 25 years of abuse were filled in and blended into the hull already.
Painting the bottom of a race ski
- Thread starter Jhucke
- Start date
makejetskiinggreatagain
Brandon
I've heard the same thing about that too. What if you sanded it with really coarse sandpaper and then painted over that? Then the bottom would have a uniform color paintjob but the scratches would still be there to provide the rough surface? I dunno, just throwing that out there.
- Location
- seattle area, Wa
scuff the bottom of the hull in complete swaths that stretch the full length of the hull. dont do a glossy finish on the bottom, it will get too squirly imo
Quinc
Buy a Superjet
- Location
- California
I would look into whatever the million dollar race boats do.
A rough surface creates a boundary layer of air reducing drag at speed. Race boats I used to be around used 360 grit sandpaper on the bottom to break up the sub-layer of water, creating what's called a hydraulically smooth surface. Straight front to back strokes. Physics, and some engineers insist, it can increase top speed by up to 3%, but it's hard to measure/price in reality due to so many other variables that have a larger impact.
What I believe is very true, it doesn't hurt and is better than a smooth surface by the laws of physics.
What I believe is very true, it doesn't hurt and is better than a smooth surface by the laws of physics.
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Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Or just beach it several times on a sandy beach or drag it down a gravel road........... Yes, I have heard of that being done to brand new sxr's that had never seen the water yet.
Yeah this is basically what I had planned on doing. I'm going to take a piece of PVC with the same radius as the chines and go from front to back and get it nice and straight. Definitely not going to drag my hull on gravel, BK lol.
Quinc
Buy a Superjet
- Location
- California
Sounds like something the vets would tell the beginners for a good laugh.
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
As far as the SXR goes. Its a wet hull design. Anything to help get the drag down.
makejetskiinggreatagain
Brandon
I hear a black bottom deck makes it faster too 
- Location
- Washington
I heard Jeff Jacobs would drag his hulls through gravel back in the day
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Sent from my iPhone using Tapatalk
Quinc
Buy a Superjet
- Location
- California
He also said he was only running a pipe...
I've got a hard time believing this.
- Location
- seattle area, Wa
its true. obviously not for miles and miles over boulders but a short jaunt down down some milder stuff puts some nice grooves in the hull and they help it track better.
Quinc
Buy a Superjet
- Location
- California
So PJS or whoever was building skis for Jeff at the time would put in tons of money in R&D provide the ski to Jeff and Jeff would then drag it behind his car... Again if you want to know what works best look at what the guys are doing to there million dollar race boats..
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
No, Jeff's mechanic or his helper would drag it behind his car. And this is not Unlimited Hydroplanes. Nor are the million dollar race boats.
I consider my squarenose to be a million dollar race boat
Flo is da man!
Just tape off the bottom and don't paint it. Sand it down and true the chines
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Should have seen his GP hull at 2008 Nats. 750 Sxi Pro hull with fiberglass spikes dripping off the bottom of the nose rocker.
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