Flush through Hull's

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CLiff Ruckstuhl

Thinking of replaceing my through hull's with fush mounted through hull's. I should know this but I wonder if they are worth the cost? Any thoughts? I know with the racing I have done and my not leaveing a stone unturned thinking that this should be a just do it kind of thing. Cliff
 
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Alan

Do you really need an answer?? ;)

Of coarse you are going to sail faster, you knew that already. I figure in light air they are worth about 2 to 3 seconds a mile. If you do 3 or 4 races a year in the light stuff, I would go for it. While you're at it I might suggest that you enclose the opening in the hull of the prop shaft. No real money outlay, just a few hours to fabricate the enclosures out of fiberglass or some thin plastic sheeting and install. Good Luck this season. PS, did you get to talk to Jeff?
 
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Richard Marble

2 or three seconds a mile?

You are going to the expense of new through hulls for two or three seconds a mile? Have you thought about what's important in life recently?
 
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CLiff Ruckstuhl

Your right I knew the answer

I did know this and not sure why I posted it. The answer to the whats inportant in life, is yes it is worth it. We have gotten 4th in a race that I very much want to win. We missed being in the top 3 last year by 17 seconds. If I were to get just 1 second a mile on this 32 mile course I would not have 2 third place flags out of a fleet of 18 boats. Over the last 2 years and would now be working on finding more speed. Yes I have had many emails with Jeff. I was amazed at what he did with his 28.5. I have printed off his email so they do not ever get lost. I will order the through hulls after I see what I need this weekend. Any idea's on which ones? Cliff H 28.5 "Red Dog"
 
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Alan

Richard

This is a "racing" forum. If you want to talk TV's, radar antenna mounts, or new window shades, you are on the wrong page. IF, however you want to learn to sail to the very best of your ability and to squeeze every drop of speed out of your boat and win silver at the same time, then this is your new homepage. When you start to be able to sail like Cliff, you'll understand how it feels to loose a race by 17 seconds. Having flush through hulls can get you back those 17 seconds and more. I'll NEVER forget the day I beat a Swan 56 by 2 seconds on a 45 mile course. That got me 1st in class and 1st in fleet. The skipper of the Swan must hate me, but it is something that I will remeber my whole life.
 
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Alan

Cliff,

..was I right about him? The guy has an amazing wealth of knowledge!! This year he's crewing for me for the season. We go back a long ways. I've sailed with him on his Melges 24 in the Newport NOOD's and now a Sonar in one design. He got me started in Laser frostbiting in the off season, and that is what really sharpened my skills as a helmsman. My crew says I can out drive any skipper on the sound. I think their biast but I'm not bad especially in waves. Anyway we've go a ton of silver at home.
 
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CLiff Ruckstuhl

Yes you were

I wonder what it would cost to steal him away from you?? Then I wonder if I have enough $$? You had better feed him and the crew well. Getting good crew and keeping them is harder then getting all the go fast stuff done on the boat. Getting good crew is really tough. Everyone has so many other things going on. Kid stuff, family stuff and other stuff. I have about 7 guys on my crew list hoping to get 3 to show up. I need a minmum of 4 on the boat to to fly Spinnaker any less then that and we have to jump to the JAM Class. The other part is getting experenced crew. Seems all the real good guys got rides somewhere else. I have started with some less experenced crew and I am trying to build a team with guys that are excited about winning and willing to learn. I will be setting up some day long practice session's as soon as I have the boat ready to sail. Usually takes a weekend or to to get the boat put back togather. Cliff
 
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CLiff Ruckstuhl

17 seconds & Richard

Having my boat set up to be the fastest it can be for racing also blends into my crusing. Since we sail on weekends we are anchored to our dock by how far we can sail on a weekend. If we have our boat tweeked out for racing and we are crusing it means we can sail farther when crusing. I used to sail against a guy who had put this bottom paint on his boat that was supposed to last 5 years and only needed to be touched up every so often. It was about as smooth as 100 grit sandpaper. We had a smaller boat and according to PHRF he had the faster boat. On a fun sail down the lake we caught him and passed him and he was amazed at how we just rolled past him. If we had been sailing a some distance over time we would have horizened him. But allot of times it is a lot of little things that will make a boat allot faster over another boat. Alan and I are perfectionest when it comes to boat prep. We each put in allot of time making our boats fast for our own enjoyment. When we add it up all the little thing's we do it pays off big time. We are sailing to Buffalo in June as our 2 week vaction on the boat. Now a fully race prep boat might sail 20 miles father then a boat not race preped based just on all the little things. Based just on that we might if the weather is right make Buffalo in 2 1/2 days verses 3 1/2 days. In the spring I look at allot of boats as I am working on mine and some I see why I sail past them all season long. I used to race with my children ages 7 & 11. We raced against other boats with over 75 year's sailing experence on ther boats. We beat them even up as a family. Good Times! So to you it might seem like no big deal that we are nut's in our quest for boat speed and racing our boats. But what other sport can I take my 7 & 11 year old go out racing as a family and win. Allot of it comes down to all the little thing's. Cliff H 28.5 "Red Dog"
 
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Alan

Re: Thru Hulls

It's been a while but I remeber finding self sealing Marelon thru hulls for Jeff. Pretty sure they were Marelon. Anyway WM has white Marelon flush thru hulls for under $20 each depending on size. You will need to add a shut off valve. Pretty staight foward. Shouldn't be an expensive job!!
 
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Warren

Thru Hulls

Replacing thru-hulls can be very "straight forward," as another poster notes, and it can also be a nightmare, too. I replaced my thru-hulls on an aging C&C before I bought my H28.5 and it was not a fun job. To make a long and nasty story less so, the job is easier if you can get a large enough wrench around the backing nut that holds the thru-hull in place. You are in luck if you can get that nut to turn. Soak the nut with penetrating oil a few days beforehand. After a number of fruitless tries and blows with a hammer, I used a small butane torch (very carefully!) to heat the nut. I eventually loosened the nut, but then it froze and would not turn further. I finally used a grinder on the outside portion of the thru-hull flange to cut and a slot. I then used the hammer to knock the thru-hull into the boat. Whatever C&C used to seal the flange wound up taking a piece of boat with it when the thru-hull finally gave it up. I had to rebuild the hole with fiberglass prior to installing the new thru-hull....the story continues if you can stand it...
 
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Cliff Ruckstuhl

Getting the old off

I have the tools, the through hull fitting can be held inplace with a Spud wrench. Then I can use a Basen wrench to remove the nut. Just another day at the office for a Plumber. The spud wrench is used for old Radators on Boiler System's. It is the same fitting as the through hull fittings. It is a 2 person job to do it. Cliff
 
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Richard Marble

I stand corrected

I’m more into cruising than racing. I do have a question however. If you are looking at anything that will increase your speed have you looked at using copperpoxy on you bottoms instead of paint? I saw it in a boat rag a couple of years ago. One time fix, copper in color, shines like a silver penny, hard like epoxy. Sounds like it would be fast to me.
 
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Cliff Ruckstuhl

VC 17M

I remember seeing it also if I remember right it was a multi-season paint. I like the VC paint it goes on thinner than water and just seems to work real well. Interlux say's a 10% increase in boat speed because of the Teflon. Thanks for the tip Cliff H 28.5 "Red Dog"
 
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Stu Sauer

Fair in the thru hulls

I don't know if anyone else has done it, but I found it a lot easier, quicker and less expensive to fair in thru hulls when I originally bought my 28.5 in '86. Start by sanding the surounding area to clean gel coat with 60 grit, including roughing up the exposed shoulder of the bronze thru hull. Then take a flexible plastic drywall spatula and spread multiple coats of Marinetex in widening circles out from the thru hull to achieve about 6" diameter overall. Wetsand the final coat and primer and bottom paint with a hard racing bottom paint then wet sand the entire bottom. It's one thing to loose a third place by 17 seconds, but it's unbelievable when after the race scores are posted you beat all but two of the PHRF 'A' fleet on corrected time sailing in the 'cruising' division. We kill 'em in light air. ;D
 
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Alan

Stu

If you're fairing in the mushroom head into your hull, then you are changing the shape of the hull in that area. This means redirecting the water flow and causing seperation behind the thru hull. I have never seen any data on such an idea, but my first thought is that you have increased the area of seperation by a factor of 2 or 3 times. It's equivalent to moving the seperation of the boundary layer forward on the hull in those areas. That is not a good thing for your speed.
 
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Stu Sauer

Shape turbulence

I looked at it differently. The sharply raised 3/8" mushroom lip now has a taper of over 12 to 1 leading to it and away from it so I'm suggesting there is much less turbulence than would have been created by an abrupt change in flow as the water hits the (original) protrubing thru hull. I'd also agree that a completely flush thru hull should be a little less turbulence. That's just my take on it, but for the most part the plumbing thru hulls are also well back on the boat; actually further back than the trailing edge of the keel. At that distance from the bow and from the leading edge of the keel, I would expect that laminar flow of water against the hull has broken up and isn't all that smooth.
 
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