markt111

Ok does anyone have any first hand expierience with speed loss after bottom painting a hull?? I am running a hard ablative paint

I have heard a few different estimates of upto 5MPH loss, in a 60-70 MPH boat there is not too much hull in the water at speed, could you really loose this much?? I bought my boat allready painted so i have no idea what could be gained by removing

thanks

madbouyz

A friend of mine missed the golden opportunity to find out exactly how much he lost when he test ran the boat he bought with an unpainted bottom. He did'nt have the presence of mind to look at the GPS on the test run and make a mental note.

He then asked the dealer to paint the botttom before shipping it.

When he got it he was kicking himself because he could'nt remember exactly what it did before.

It's a stepped bottom 28 footer with two 350mags and I'm sure he's dropped 3 maybe 4 mph.

BY U BOY

between 3 to 5mph sounds right. When i painted my CC i lost 4mph. After talking to some people i rubbed the bottom back half with brass wool and gained 1.5mph back

markt111

BY U BOY what type of CC are you running? what speeds? nothing else was changed when you painted set up etc...

BY U BOY

marylandmark is correct. A 1999 proline 200 sport with merc 150. I did not change anything on the boat.

stevesxm

5 or 6 mph at 60 mp is about 50 or 60 hp worth of drag. there is no paint on the planet that will do that if the ENTIRE hull was in the water. whoever is telling you that is full of crap. 1 mph MAYBE... and it would have to be the worst paint ever made w/ big rocks in it.

BY U BOY

Then why is it i lost 4mph verified with a gps?

Bottom was prepped properly and i painted the hull myself.

stevesxm

i don't know. but the math doesn't lie... ever. just do the mph increase vs drag equation for 60 mph.... the numbers are obvious. there are a million reasons why you can lose speed but the fact is that the differences in the very best and most "slippery" bottom paints vs the stuff you buy at k mart is less than .05 % ...

i mean really ... on my boat the dif in a tiny bit of trim and a tiny bit of chop is good for a couple 100 revs and a couple mph...

whatever you are experiencing... its not the paint.

honest

BY U BOY

I have to disagree! I bought the boat brand spankin new had it in the water for three days then painted it. 3.7mph decrease in speed. Boat was actually lighter on fuel and one less person on board so if what you say is true i should have gained speed.

Don't get me wrong i am not trying to pick a fight i am just giving my real world experiences that the post ask for.

markt111

I appreciate the info BY U.. this is th type of result I have heard too, just don't know if it is common

anyone else have first hand expierience?? lets keep it tame