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Closet Powerboater
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3,925 Posts
Discussion Starter · #1 ·
Nevermind the hole in the hull in the picture, I used to own a wooden boat and am used to holes in the hull. The thing in the hole? That's a margarita blender. ;)

The question I have is what about all the roughness everywhere else. Is this just layers of hard paint that are unevenly worn or something more sinister? Is this something that will eat 1/thousandth of a knot due to excess friction, or is is more of a real issue? Need/should be fixed?

The boat apparently has blisters, but I don't see them. Is this evidence of someone taking the tops of all the blisters?



Medsailor
 

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Bristol 45.5 - AiniA
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4,525 Posts
A bit hard to tell from the picture but could it be related to the installation of the blender, if it an add-on? The pattern appears almost circular around the thruster. Perhaps when it was installed they got the bottom nice an smooth there, but the rest of the hull needs to taken down to the gelcoat to get everything nice and smooth.
 

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Sailor
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935 Posts
Looks to me that there is buildup of paint and areas have flaked away. Those areas were simply painted over, hence the roughness. I see the area that looks like there were pockmarks - I would think that if there were blisters, the PO would have faired them at least. In any case, not too deep. It will just cost you a part of a knot in speed and give you more time to enjoy margaritas from your blender.

No worries.

At some point you may want to take everything off so you don't have thicker and thicker bottom paint that flakes off. At that point you can fair as you see fit with west system. Then use a multi season ablative paint and only touch up where needed.

Tod


Mandolin, Bayfield 36 out of Rock Creek, Chesapeake Bay.

Sent from my iPhone using Tapatalk
 

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I agree they do not look like blisters, but it is odd that someone went through the trouble to paint over such a rough surface. Prep work is the most imporant part of any painting job, and it was not done on that hull. It might prompt me to look for other short cuts on the boat that might have been done to pretty it up for sale without dealing with bigger issues.
 

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Master Mariner
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9,225 Posts
I also think this is just a paint build up. Numerous haul outs with flaking paint scraped off, then applying the new paint on top of the old. No biggie, IMO unless you are a super racer. One day, when finances permit you could strip to gel coat, barrier coat and begin anew, but I doubt you'd gain much speed and few people are going to be checking out the old girl "under her skirt" so to speak.
 

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Closet Powerboater
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3,925 Posts
Discussion Starter · #8 ·
MS,

It's a BFD....it will slow you down by at least 1/4 knot. Fix immediately or you'll be the laughing stock of the ORC.

;)
Slow I may be, but I'll win them over with my margaritas!!! Now let me just nose my bow up to that glacier in your avatar and chew up some more ice. :D

MedSailor
 

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Are you sure that is a hard bottom paint? It looks very characteristic of an ablative bottom that hasn't been striped in a while. More disturbance at the waterline, overly thick paint, pretty uniform distribution... It looks like every other ablative bottom I have seen in need of striping. Or you could just slather some more paint on and be done with it. No ablative bottom will ever be all that fast.

The general consensus is that going from a terrible bottom job (pretty much what you have now) to a world class bottom means about ..25-.5kn in light air, with decreasing importance as the wind builds. A simply average hard bottom is probably 80% of that gain, but much less expensive and time consuming.
 

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Closet Powerboater
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3,925 Posts
Discussion Starter · #11 ·
Are you sure that is a hard bottom paint? It looks very characteristic of an ablative bottom that hasn't been striped in a while. More disturbance at the waterline, overly thick paint, pretty uniform distribution... It looks like every other ablative bottom I have seen in need of striping. Or you could just slather some more paint on and be done with it. No ablative bottom will ever be all that fast.

The general consensus is that going from a terrible bottom job (pretty much what you have now) to a world class bottom means about ..25-.5kn in light air, with decreasing importance as the wind builds. A simply average hard bottom is probably 80% of that gain, but much less expensive and time consuming.
Good eye! Further research reveals that it is West Marine PCA Gold bottom paint. Ablative.

MedSailor
 

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snake charmer, cat herder
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2,651 Posts
you have a formosa/ct. we dont get blisters but our bottom paint CAN build up and do that ugly thing yours did...my other boats did that also. no big deal. it is the bottom paint. blisters are larger rounded bubbles that look like quarter sized lumps.
repeat..formosa and ct dont get blisters. we get voids and other weird stuff, but not blisters.
 

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Closet Powerboater
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3,925 Posts
Discussion Starter · #14 ·
you have a formosa/ct. we dont get blisters but our bottom paint CAN build up and do that ugly thing yours did...my other boats did that also. no big deal. it is the bottom paint. blisters are larger rounded bubbles that look like quarter sized lumps.
repeat..formosa and ct dont get blisters. we get voids and other weird stuff, but not blisters.
Don't worry, this isn't on my Formosa. I know they're strangely immune to blisters. This photo is a boat I am looking at buying. Frankly, if my formosa had a bow thruster, I might not have been so tempted to look at other boats. Her limitations sure have taught me a lot about docking, but man, I'm looking forward to a boat that is easier to dock.

MedSailor
 

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I think there are a combination of things going on. The ablative flaking can be repaired. It is less noticeable around the thruster, likely because the add-on was faired with epoxy, making a better bond. Maybe faired that way at the factory?

If I were to buy her, I'm sure I would budget to have her bottom taken down and faired properly, then barrier/primer coated and repainted. Should be good from there. Good over bad always eats at me.

Good luck in the search. While some get on their high horse over thrusters, they can truly be necessary in some circumstances, particularly with larger boats and larger windage. Of course, one should feel they can dock without it and keep its use to a minimum, to insure you still have some basic skills. But, I say margaritas for everyone over 40ft!
 

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Closet Powerboater
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Discussion Starter · #18 · (Edited)
The stern was never really the problem for me. What I found, is that the pivot point of the boat, i.e. the axis around which it turned, was directly under the mizzen mast.

The problem is, that the bowsprit is 40 feet in front of that point. So any windage in the forward part of the 50 LOA tried to blow the bow off. The further out the windage, the more leverage.

Basically, my bowsprit acted as a unidirectional wind powered bow thruster.

I got used to taking it into account, and getting really good at pausing at the helm and playing the multiple vector game in my head before untying the lines (in order!). I suppose with a stern thruster I could crash into a dock broadside, instead of just with the bow and decrease the risk of snapping the sprit off, but that's a marginal gain. ;)

The only time I really needed a stern thruster was when I poached a slip for a few minutes to get fresh water, then found that there was such a strong crosswind coming from the starboard side that I'd never be able to back out and swing the bow around to starboard. There was also a current running in the fairway port to starboard which would catch my stern as I backed out and multiply my starboard prop walk. Basically, I appeared screwed, or perhaps could try and back out and give in to the starboard trurn and hope to back all the way down the fairway (you know how these boats back) with the wind and current.

What I ended up doing was hoisting the mizzen and sheeting it flat amidships, and backing up. The mizzen became my unidirectional wind powered STERN thruster to counteract my unidirectional wind powered bow thruster (bowsprit) and it worked marvelously! My stern was turning to port, and when I no longer needed port stern thrust, I blew the mizzen sheet. :)

If I had a bow thruster, I never would have had the "opportunity" to be so creative, and test my theories of docking in real time in crowded places. Minniwaska's point about keeping your regular skills up and not using a bow thruster as a crutch is well taken, but if I do buy a boat with a margarita maker up front, for a while at least, I'm going to be using it with every docking just for the novelty. Expect to see boat dressage in the marina!

MedSailor
 

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snake charmer, cat herder
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2,651 Posts
lol so you wish to slalom thru the leaky teakies joyfully singing halleluyah chorus at speed in the anchorage just for fun and grins... okshowoff..we love ye still....lol

just toss me a root beer float on your way by, please...i kinda miss those

seems to me that a smooth bottom makes no difference in cruising venue than a slick smoothie....the extra dough per hour at 105 usd per hour isnt worth the attempt to sickify them. yes it makes a difference with a light racing boat, but with a heavy cruiser, no difference..i tested clean bottom 4 kts. dirty bottom...4 kts. what is the big huge deal...we aint racing.
 

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What is the boat? as the gel-pox looks very similar to that found on certain pre-vinyl ester boats of the 70s & 80s; and, the probable cause is poor timing and imperfect cure of the gelcoat as sprayed into the mold before subsequent layers such as the (cosmetic 'cushion') matting layer was applied. This is usually 'hydrolysis' of the gelcoat layer and rarely penetrates down into the cosmetic matting layer and usually never into to the structural roving layer. Pearsons, and similar boats of this era are 'famous' for gelcoat-pox and is only cosmetic and really doesnt warrant a complete 'bottom job'.

The causes of gelcoat pox are many: gelcoat was sprayed on a Friday afternoon with the boat & sitting curing all weekend and the matting layer, etc. work restarted on Monday morning; they sprayed the gel using an oil lubricated compressor that shot out small 'packets' of oil; they didnt use an 'air dryer' on the air compressor and water got into the gel as it was being sprayed .... the air line was 'spitting' water, air compressor didnt have a particulate filter applied, improper or varying catalyst to resin ratio (poor mixing/metering INSIDE the spray gun), etc.. Gelcoat pox is usually 'hydrolysis' that occurs only in the gelcoat layer - an analogue of rusting in polymers.

Only way to tell for sure is to carefully 'chisel' away the gel and see if the gel is actually adhering to the matting layer; OR if indeed, its a simple paint failure. That the area near the retrofitted bow thruster is smooth and the area not near the thruster is 'rough' seems to me to be indicator of gelcoat failure or gelcoat-pox. If gelcoat pox, dont go overboard with a DIY repair but simply 'fill' (trowel-in) 'filler' to get the hull somewhat smooth (you can use 'thickened' paint and a polyethylene to do this 'filling & fairing') ... but realize that the fairing will not last more than a year or two or three.
 
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