Question? Does a polished hull increase efficiency?

[Eddy]

Thanks for all the good input, sounds like a case of if it ain't broke don't fix it. Sounds like way too much trouble for questionable results.
One other question though, maybe I'm dense but I still can't figure out what her thighs being wet has to do with this?

[Dirtguy]

Originally Posted by Lake

From the people that I've heard about they don't see any real improvement in fuel efficiency, and a very slight increase in top end speed.

had some experience years ago with Pontiac Motorsports and their drag boat program. At that time, the class leader was using a "fish scale" type finish and had some dat to back it up. The post taht said it breaks the surface tension was right. Water grips the hull on a microscopic level. And as we all know, liquid slides better on liquid than a solid surface. Oil in an engine keeps the metal pieces form touching. So water gripping the hull would lube better.

So, the short story is to leave it alone as it's too tough to remove and it might actually be helping to let the boat glide "water on water" a bit better.

For ported heads, the rougher finish makes more power and flows slightly more than a mirror finish.

DG

[Spokaloo]

Another thing to look at for the information you are seeking is to google Savitsky and Boundary Layer. There was some serious research done to figure out how to make boats plane more efficiently and to poke a hole through the water with less hp.

E

[dbar]

Originally Posted by zarco

When I was into the "go fast" boats. You did not want to wax or polish the bottom as it creates friction or suction. A lot of guys would sand the bottoms ever so slightly to gain a minimul amount of top end speed. The roughness would create air bubbles to break the friction or suction. These were boats doing well over 100mph so I don't think it matters on a " fishing" hull.
Also there is a product to remove bottom paint without sanding it off. Can't remember the name of it ??? But you brush it on then cover with special paper, wait then scrape it right off( or wash it off). Worked perfect on my center console when I got it.

I would love to know what it was!!!! I want to remove whats left on my hull. The boat had it when I bought it and its been rubbed off by the skids on the trailer, iwould rather remove it than repaint it!!!!!!!

[BiggestT]

All I can say is that I went through the same experience on my Blackman. Removing the ablative paint was a bitch and a mess. I stopped half way. Furthermore, I concluded that it made little difference with a 20 knot diesel powered boat. Maybe there is gain to be had on a go fast boat, but not at sportfisher cruising speeds.

[?? fisherman]

Originally Posted by dbar

I would love to know what it was!!!! I want to remove whats left on my hull. The boat had it when I bought it and its been rubbed off by the skids on the trailer, iwould rather remove it than repaint it!!!!!!!

Hey Jim ~

Check the old thread that I did on Chucks whaler project, and you will see the pics of the bottom paint removal that Chuck accomplished. Chuck was able to remove the bottom paint and make the entire hull look amazingly new!

The product he used was purchased at West Marine, and I believe it was called Peel Away, or something like that. Basically you brush on this gel like product and then put on a type of paper over it and let it sit for quite some time, and then later you pull off the paper and then scrape the bottom paint off with a putty knife. It works pretty good except it's a very messy process, and to get the final results that Chuck did takes alot of fine wet & dry sanding as well....... but his boat came out INSANE!

Here is a link to the whole Whaler transition with numerous pictures of the bottom paint removal.

http://www.bloodydecks.com/forums/ch...ex-change.html (Rebirth of a Whaler/Whaler Sex Change)

The unknown fisherman

[MATTANZA]

heavy duty paint and epoxy remover wil take off bottom paint... very hard on gel coat, though. get it @sdmx.

[zarco]

Peel away . That's it. I got the idea from chucks post back then. Worked awesome.

[Vigilant32]

It made a difference on my Whaler25 & Whaler27. Spent the time to take the bottom paint down and off to the original gel coat finish.

These boats did 55 & 50 mph and overall they seem to ride smoother, and did pick up some mileage. When burning 225 gal of fuel, even .2-.4 increase made it matter on longer tuna runs, jmho. No science, just my findings.

It made my hull worth more without the bottom paint, but that may be a Whaler resell thing!

My uncle held the world record in blown alcohol flatbottoms for many years, his Cole Marine hull was pretty slick from what I remember.
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