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Bottom paint Vs Gel coat

Posted: Jul 12th, '10, 13:35
by Kevin
I have always wondered if there is a noticable diffence in our Bertrams cruising speed when the bottom paint is removed and new gel coat is put on. I have seen the difference in 50kt go fast type hulls but never ours. Guess I have been dreaming about storage on a boat lift instead of in the water. Will it help speed and economy?

Posted: Jul 12th, '10, 15:55
by Bruce
Waxed gel coat is a much slicker surface than bottom paint in resistance which equals drag and fuel usage.

Doubt you'd save enough to go to the trouble and expense of putting in a lift, grinding off the bottom paint and regelcoating the surface.

Besides I've seen gel coated boats in the water for only 3 days start to get barnacles. Something to consider if going on trips for any time.

Posted: Jul 12th, '10, 16:52
by scot
I have seen paint companies advertising the slickest bottom paint, etc for the blow-boat yatch racing crowd. It is expensive stuff, not sure how it holds up, or how finicky it is?

Posted: Jul 13th, '10, 04:56
by Buju
How 'bout bottom paint that thinks its gelcoat?
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http://www.yachtpaint.com/usa/diy/produ ... epoxy.aspx

Posted: Jul 13th, '10, 11:28
by JohnCranston
Buju,
That's what I went with. Smooth as a baby's butt, hard and shiny also.

Posted: Jul 13th, '10, 11:34
by Craig Mac
I remember reading that too smooth may not be good---like a dimpled golf ball --less surface tension??

Also not to wax bottom of boats that are not bottom painted---

Posted: Jul 13th, '10, 20:52
by Kevin
John,
Is that paint something you switched to or has it always been on your boat?

I guess most of us have never had 30 years worth of bottom paint completely removed and started fresh. I almost wonder if you would have to add some pitch or cup to your props. Maybe I should call Myth Busters!

Posted: Jul 13th, '10, 21:46
by John Swick
Kevin,
We used that stuff like that when refinishing my B25 about 5yrs ago.
Sandblasted, barrier coated (multiple layer process) then the interlux VC 17 (same stuff?) with a slightly dimpled finish.
Hard bottom paint w/minimal antifouling properties.
Not sure if there's a performance improvement cause I had not previously run the boat.
From 10' it looks like the boat just came out of the mold.
The guy that did the job, suggested that if it stains, then just antifoul over it.
I do leave the boat in the water from time to time for a week or two and other than some scum at the water line that comes off with a soft brush, the bottom looks as good as when I had it done.
There's another guy that frequents this board that used the same stuff and kept his boat in the water on the east coast (salt water).
He'll hopefully chim in the next few days as I think he's on a road trip right now.
Cheers,

Posted: Jul 13th, '10, 21:46
by coolair
so waits a bottom paint, but no anti fowling properties so does stuff grow on it,

John is your boat at salvadors yet?

Posted: Jul 13th, '10, 23:17
by JohnCranston
Kevin,
We went all of the way to the glass. I used to have Micron 33, but, after this last rebuild we decided to re-gel coat the bottom. After a $5k bid to do the gel coat, we went with the VC for $1k. Innerlux said that if we wanted to go back with bottom paint, we could go right over the VC. They said that VC would work as a barrior coat. The boat will stay in our cradle lift and not in the water.
Matt,
After our last pm, half of that punch list is done, and after Steve gets back from Poco, he should finish up the rest next week. If so. I'll let him give me a bid on those coolers. We'll see.

Posted: Jul 13th, '10, 23:29
by JohnCranston
I meant barriercoat.

Posted: Jul 14th, '10, 21:02
by Sean B
Kevin,

Before the Bertram, I had a Pro-Line that came factory with a Donzi (gelcoat) hull. Fast boat. 50 knots wide open, and could cruise at 40 knots.... at least until your dental work came loose anyway.

I grew weary of the whole trailering drill really quick, and started leaving it in the water for a few days at a time. As Bruce said, the hull would get fouled up real quick. After three or fours days of growth, the boat would barely come up to plane. Had to pull it out and pressure wash, scrape, and muriatic acid wash to make it right again. A real PITA.

So I decided to paint the bottom with hard antifoul. The paint stole a lot of speed: top speed reduced to 41 knots, and the cruise speed came down to 30.... it was quite dramatic.

Not a Bertram or even a Bertram-like boat experience... but it's the best I've got

Posted: Jul 15th, '10, 17:18
by Kevin
Sean,

That is very noticable. I was able to run a few boats from the factory in that speed range. I do not remember losing more than 3 knots after the bottom paint was added. This was about 8 years ago........memory might be off a bit.

Bottom painting around here is about 1000 for a decent job. Ten years of that is well more than what I can get a lift for..........if I had a house on the water.

Posted: Jul 15th, '10, 20:09
by Face
My sailing buddy says wax on paint or gelcoat is actually slow. I forget the product they treat painted hulls with but I can ask him. One of the products they use is teflon based.

I had a Stamas 26 that I ran for the past 5 years or so. It was on a lift and had some bare areas and some areas with 5 or 6 layers of bottom paint. I had it blasted and then I barrier coated and re-applied anti-fowling paint. I picked up 3-4 mph with the small block at the time. You could actually feel the "smoothness" in your feet and in the seat. Later topped out at 43mph per gps with a carbureted 454. That was the perfect powerplant. I regret selling that boat but eventually I'll have my B28 done.

Posted: Jul 15th, '10, 21:02
by bob lico
sean on the dramatic side we have a 32' skater cat at the marina that i test drove 104mph in rolling swells .the first year the guy paid to take it out every week and acid wash. got to be expensive so he bottom painted with a ablative bottom coat .the boat slowed to 97mph quite a differants .he ended up removing bottom paint and restore gel - cote and kept on lift from then on.a expensive lesson learned. oem gel-cote is the fastest but not practical for a 31 bertram that is used to fish next best is barrier cote and top cote of ablative .i have slowed down about 21/2 knots at w.o.t. so far this year .slime and bannacles taking there toll in abnormally warm water .

Posted: Jul 16th, '10, 00:16
by Sean B
bob lico wrote:sean on the dramatic side we have a 32' skater cat at the marina that i test drove 104mph in rolling swells

Bob if I ever make it up your way, can we go for a boat ride?

Please?

Posted: Jul 16th, '10, 07:27
by Raybo Marine NY
bob lico wrote:sean on the dramatic side we have a 32' skater cat at the marina that i test drove 104mph in rolling swells .the first year the guy paid to take it out every week and acid wash. got to be expensive so he bottom painted with a ablative bottom coat .the boat slowed to 97mph quite a differants .he ended up removing bottom paint and restore gel - cote and kept on lift from then on.a expensive lesson learned. oem gel-cote is the fastest but not practical for a 31 bertram that is used to fish next best is barrier cote and top cote of ablative .i have slowed down about 21/2 knots at w.o.t. so far this year .slime and bannacles taking there toll in abnormally warm water .
this may the first time I have heard of a bottom painted Skater- man what goes through people's heads?

I would beg borrow or steal to have a lift, the look of a boat with no bottom paint is stunning in comparison to even the best bottom paint job, and in the long run you could save yourself money and definitely increase the value of the boat.

We have a customer who HATES bottom paint, he had us remove the paint from his Tiara, I thought he was crazy for bothering with it because he did not even like the boat. His brother in law lives 2 doors down- both Tiaras up on a lift, his has no paint his brother in laws does- they look like 2 different boats, one looks like a turd and one looks like a new yacht

We have sprayed Imron on alot of bottoms, and Skater sprays them on the boats out of the factory

I have had 2 people CLAIM their boats were faster with the Imron then when they had original gelcoat on the bottom. Gelcoat sprayed without the benefit of being in the mold does not have the same quality as re-sprayed gelcoat, but it is still better then bottom paint.

Look at the difference on that Tiara, it is in the backround of the first picture, so much cleaner.

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Posted: Jul 16th, '10, 14:32
by bob lico
robbie i agree,agree agree BUT life and the marina business being what it is, first you pay up front for the slip at the lenth of the lift . then you pay for the lift at list price plus 40% then you pay the yard electrician at 150.00 a hour to bring in a service to the lift plus electric at 20% markup so the put the cat on a lift was 24,000 a season . thats why he said fu-k it paid the bottom. this was a pleasure boat.

Posted: Jul 16th, '10, 14:37
by bob lico
SEAN B anytime just give me two days notice and tell me what you want to drive.

Posted: Jul 16th, '10, 15:08
by Kevin
24,000 per season..............I just vomitted in my mouth!

Posted: Jul 16th, '10, 15:26
by Raybo Marine NY
bob lico wrote:robbie i agree,agree agree BUT life and the marina business being what it is, first you pay up front for the slip at the lenth of the lift . then you pay for the lift at list price plus 40% then you pay the yard electrician at 150.00 a hour to bring in a service to the lift plus electric at 20% markup so the put the cat on a lift was 24,000 a season . thats why he said fu-k it paid the bottom. this was a pleasure boat.
Bob- I meant the lift for someone's boat in their own yard, if you want to run a 32 Skater you know what your in store for.

I dont know if you could pick a worse boat to put bottom paint on, talk about killing resale no one would want to touch the thing, everyone would think it had some major damage that was covered with bottom paint. You want to play you got to pay.

I thought your marina had high and dry storage? I looked at a Scarab over there and what he told me he pays sounded VERY reasonable, cheaper then a wetslip.

Maybe if I had a marina I would have 2 nickels to rub together!

Posted: Jul 16th, '10, 16:46
by JohnCranston
Robbie,
I hear ya on the 2 nickels to rub together...that's some big numbers that Bob's talking about...if you're gonna play, you've got to pay.
Some folks can swing it, unfortunitly,not this guy.

Posted: Jul 16th, '10, 17:04
by Raybo Marine NY
I could not afford a large boat even if someone gave it to me for free

Posted: Jul 16th, '10, 22:04
by JeremyD
From my one design sailing days -

you want

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Dry Film Lubricant. Not wax - it will make you slower

Posted: Jul 16th, '10, 22:13
by bob lico
here is a deep pocket dude who will pay the price for no bottom paint.this is a fountain c/c fishing boat not a go fast boat but as robbie said a boat with no bottom paint gets the highest price resale. the lift is practical in your back yard ,at a private marina it is gold!!!

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Posted: Jul 16th, '10, 23:05
by Sean B
Kevin wrote:24,000 per season..............I just vomitted in my mouth!

Those of us who labor without a badge in their wallet usually risk getting arrested for that sort of thing.

Bob, I want to drive something "dramatic"

Posted: Jul 16th, '10, 23:25
by coolair
robbie
that 21 whaler for sale?
there was a beautiful 31 called bullet in freeport tx with no bottom paint, kept in a cradle in a warehoouse. idk where any pictures are maybe cranston knows

Posted: Jul 17th, '10, 07:22
by Buju

Posted: Jul 17th, '10, 09:36
by Raybo Marine NY
coolair wrote:robbie
that 21 whaler for sale?
there was a beautiful 31 called bullet in freeport tx with no bottom paint, kept in a cradle in a warehoouse. idk where any pictures are maybe cranston knows
the price tag would be astronomical, he has a ton of money into that boat

Posted: Jul 17th, '10, 10:12
by bob lico
robbie i should have mention one of the yardman ; joe is the go to guy for nice bottom paint jobs. what he did for the guy in the cat was to mix a matching hullside color (red) then painted to 1" BELOW the water line and no bootstripe . the dude only had to run a long handle brush with bleach on scum line . you would never know the boat was bottom painted unless it was out of water block up and see the paint line. he also uses white bottom paint on those 350,000 everglades with fanatical "don`t paint bottom owners ". like i indicated good in theory but a real p.i.t.a. basicly a losing battle to keep the bottom clean, even in light of a dimishing selling price down the road. trailer boat on long island is really tough especially with 35' go fast boat ,very few ramp that long to launch with 36' trailer .you know the story when wheels fall on bottom of ramp -----ouch!!
so they try the forklift with slings to remove boat off trailer and put into water.-expensive!!! the cats can`t go in high and dry do to non -compatible with giant fork lift.

Posted: Jul 17th, '10, 10:16
by Raybo Marine NY
some of those trailers are such a work of art its a shame to put them in salt

this trailer never sees the salt, slings/hooks only ( I had to fix both sides where it says SKATER 50SS, 10 colors with 4 of them originally mixed with "a little of this and a little of that"

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Posted: Jul 17th, '10, 10:37
by bob lico
your the best! nice work ---back in racing days showing off the trailer was part of the act . a fully crome 40' trailer to carry cat on 30 degree angle was top gun as i remember. tractor trailer had two spare engines in tanden behind cab, and work shop in front. all custom painted. just memories now.

Posted: Jul 17th, '10, 12:40
by Face
JeremyD wrote:From my one design sailing days -

you want

Image

Dry Film Lubricant. Not wax - it will make you slower

Jeremy, my friend sails 505's all over the country. He mentioned a product with some name/acronym like PFPDE. I probably have it all wrong. A teflon product, wipe on, drys in minutes, wipe off. Heard of it?
-Joe

Posted: Jul 18th, '10, 08:14
by JeremyD
PTFE (polytetrafluoroethylene telomer) Similar to the McLube I posted. Some you spray - some you wipe on. Saw a guy apply to his Flying Dutchman once on the trailer (20ft performance boat, narrow beam, around 400 lbs.) he went to launch the boat, forgot to reattach the bow eye. When we tilted the trailer back, to drag it to the hoist, the hole boat slid off the trailer on to the ground... :shock:

It's like magic really if you've never used a dry lubricant before. Works like WD40 - but without the greasy mess.

I used to race 505's too great boat.

Posted: Jul 18th, '10, 22:54
by coolair
Thats it Buju, suposedly that is a fast 31,
robbie
Figured i would ask, i gotta come up with a bay boat, but i dont need a project right now, turn key for me