Best surface

[dawgdude]

Trailers complete now and I've graduated to the bottom of the Kona's hull. I'm in the process of removing what little hook was left after I finished replacing the stringers.
Question??? From the small amount of experience I've had, (alot gathered from this site and others, you guys can really get into some in-depth conversations), with the bottoms of Jet Ski's, Bathtubs, Spatula's, Etc. It seems that you really don't want a perfectly smooth bottom or running surface. I've heard it said that a smooth bottom creates tubulence, (air bubbles). Here's the question. After shooting color should I shoot my clear then ruff it up or is there some other coating that I can apply to the bottom that will acheive the same effect.
At this time I'm not going to be running alot of HP. Mabey 450 to 500, so I need to make sure that I maximize all the other areas, such as the bottom, that I can for speed.
Thanks, Dawg!

[Squirtcha?]

This would probably be your best bet (very bottom of the image). Lubribond's (SPEEDCOAT) . It's not pretty (only dark gray) but it can actually add some speed. You don't need to do the entire bottom, just the back 4-6 feet or so (on plane area depending on how much hull you have in the water at speed). All jetboaters that see it know what it is, so it's kinda trick. You'll see if on almost every boat that's had bottom work done to it (setback pumps, reset intakes, blueprinted bottoms etc.)
http://www.rexmar.com/images/page136.jpg
Here's a picture of the bottom of Brendellajet's boat. He just had the bottom done by Jeff Bennett who is probably the premier boat bottom guy in the business. If he's using it, you can bet it works.
http://www.***boat.com/image_center/...0_0598-med.JPG

[dawgdude]

Actually Brendellajets thread is what got me to thinking about the running surface. I wasn't sure what he had on his when I looked at the pictures. I guess you just spray it on and walk away. I saw a number in there to Bennett also. Might give him a call. Not to many guys round my area that I've found to discuss this kind of work with.
Thanks for the advise Squirtcha.

[460rogers]

have you talked to Mike's pump and speed in houston yet?
They have been very helpful to me.218-820-1559
WE BE COOL !!

[Squirtcha?]

No problem dawg.
Forgot to mention though, it needs to be reapplied or touched up every so often. It does tend to scratch/wear off after a while.

[HOSS]

Not all hulls benifit from a rough surface to airate the water resulting in less surface to water contact.

[youngster]

how long does the "speed coat" actualy last?

[Squirtcha?]

Never heard that Hoss. Not saying it aint true..............just that I never heard it. Do you know of a case where it slowed someone down?
I'm not sure how long it lasts. I suppose it kinda depends on how many times you rub it across abrasive stuff like sand, rocks and the like. I know I've got some scratches in mine and it was just done last year when I had the pump setback. Nothing serious but could still use a touching up.

[dawgdude]

460, I have tried several times to get with Mike but as of this time no luck. I keep missing him. There are several guys down here that have used him over the years with their race boats. I'm hoping that he can help me out with this pump, that is if I ever get to it.
Squirtcha, I'm not to worried about to much about having to redo it every so often, especially if it'll give a little on the top.
Like I said Hoss, I'm not all that experienced with this stuff,,yet,, but I did play around with my gp1200 ski and gained 3 mph by working the smooth surface off of it. Seems to me that this is basically the same principle. I've talked with a guy here at work that is a phyisics guy and has explained it to me. I'll have to write his explanation in here someting.
Anyway thanks for all the help.

[HOSS]

No need to write an explanation from a physics major here. But if you want to I think thats cool.
I know a guy with a checkmate that lost speed. he said it was slower out of the hole and didn`t feelthe top speed gained at all.
It only helps a boat which spends its entire life in the water. To break it down even more this means a hull in the water. In other words. if your boat at speed is mostly out of the water(like a pbass boat on a pad) then it will not help. Further if you run in any chop(even very light) the added weight along with the resistance caused by the rough surface causes even more friction when that portion of the hull comes in contact with the water for its brief moment. Does a flat rock skip further than a rough rock?
Now to extract what the physics major probably told you.
The rough area on the bottom of the hull causes the water to airate. meaning air with water running along the underside of your hull. Knowing that water has a very strong molecular bond you could easily see how air int he water would be less restrictive. I meen who doesn`t know that air flows across a surface easier than water. That meens it is less restrictive. This is due entirely because of the molecular bond of each surface.
Now if you are running on an extremely smooth liquid surface whereas the hull of your boat is always in contact with the wet surface then it makes since to try and have a less restrictive surface. Hence airating the water for a less restrictive surface. But if your hull`s life is spent mostly in a non smooth surface then that meens your hull is not always in contact with the wet surface and is already mixing with a less restrictive surface. This is when the smooth rock and rough rock skipping comes into play.
An offshore rig does not in any way benefit from a rough hull surface. This is why in no chop they are slow. Surface (hull) to water retention. And why would you speed coat the bottom of an offshore rig? Its life is spent in chop. The speed coat would then become the rough rock. It would be restrictive.
I did mine because I have a heavy(20` Southwind) ass jet. My hulls entire life is spent in the water. I used rock guard (the kind in a can that you spray the rocker panels of your car before paint) on my hull and shot many mills over it.
Again, sometimes its best to have a flat rock.