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  #1  
Old 07-05-2011, 03:36 AM
frasco frasco is offline
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23' plywood sailboat on a budget - no glass?

I'm on a budget so I was wondering, would it be sufficient to coat the hull with epoxy only or does it need glass? I realize leaving out the glass would make the hull less stronger but with 1/2" plywood it should be enough. Lifespan is another thing, and what I'm mainly concerned about. And.. if I want to put glass on it I could always do it later (in a few years), right?
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Old 07-05-2011, 06:41 AM
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PAR PAR is offline
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It depends on the build type, as some require the fabrics for waterproofing and additional panel stiffness. Assuming your design just uses the 'glass fabrics as a abrasion resistant sheathing, then no you don't absolutely need it. Light weight fabric sheathing are typically just this, unless over seams or other joints at which point there serve to hold the joint as well as seal them.

Durability is more a function of care then sheathing schedules. If you routinely look over the hull for dings and nicks, then you'll catch issues before they become major concerns, regardless of coating type. If you don't preform regular inspections then the boat will deteriorate fairly quickly with or without the sheathing.

What type of boat, build method, what weight 'glass do the plans say and where does it go, etc.?
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Old 07-05-2011, 07:07 AM
frasco frasco is offline
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It doesn't have plans per se, my father designed it and built it hull-ready but didn't have time to finish it. The hull was just spackled and painted (the deck was glassed though) and had been left that way for 20-30 years. I recently took on the task to learn how sailboats work and finish the boat. I've sanded most of the hull now. Did a few calculations and realized that glassing is pretty expensive considering my limited budget so I started thinking about alternatives.

I will rig it with a keel-stepped mast so the extra strength in the deck is good but I'm unsure about the rest of the hull..

Here are some pics:









One of dad's original drawings:



And mine:



Checking is probably an issue if I only use epoxy? There are a few cracks in the spackel/paint from before.

On the other hand, epoxy isn't that cheap either so the savings aren't that huge..
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Old 07-05-2011, 07:38 AM
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lewisboats lewisboats is offline
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Unless that is cold molded I highly doubt that the hull is plywood. If it is cold molded the laminations are probably stuck together with epoxy anyhoo and only the exterior veneer would not have epoxy on it (highly unlikely either). perhaps you should pick a small spot and sand down to the substrate and find out what it really is. The deck may be ply and you say it is already glassed so you shouldn't have to worry there provided it was done properly. It looks to be quite well made...at least in the pictures. Find out what exactly the hull is made of.
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Old 07-05-2011, 11:29 AM
frasco frasco is offline
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The hull and deck are definitely both (marine) plywood. I'm a bit confused about the terminology as english isn't my native language but to explain, the boat was built on a temporary frame which was removed after the plywood strips were bent, stiched and glued in place. The longitudinal frame was left in place, you can see it here:



The interior is painted white (no other treatment). Is this technique called cold molding?
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Old 07-05-2011, 01:56 PM
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gonzo gonzo is offline
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Yes that boat is cold molded. There is no problem with epoxy or coating without cloth. There is already a coating, so you may want to find out what it is before recoating. I used to race an IOR onetonner in the late 70's. We ocean raced and cruised extensively for years. I saw her last year in very good shape. The hull is cold molded with epoxy paint, not resin over it.
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Old 07-05-2011, 02:20 PM
Steve W Steve W is offline
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I concur, you dont need to glass sheath, i always do but last year did major repairs on a searunner 25 which was only epoxy coated and at 28 yrs old was in excellent shape.
Looks like your dad did good work, well worth saving imho.
Steve.
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Old 07-05-2011, 02:24 PM
frasco frasco is offline
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Thanks for clearing that up. Looking at your avatar it's hard to believe you raced in the 70's.



I'll look into epoxy paints and I'll try to find out what the clear material (besides the white paint and white spacke) is. The dark spots in the picture appear a while after sanding (and are easily sanded off)... clues?
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Old 07-05-2011, 02:26 PM
Steve W Steve W is offline
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Btw, your boat is cold molded but he may well have used marine plywood ripped into strips instead of solid wood veneers.
Steve.
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Old 07-05-2011, 02:27 PM
frasco frasco is offline
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And btw, would you suggest to sand all the way down to the bare wood or will the epoxy paint stick to the spackle (I'd of couse sand down any cracks)? I'm under the impression that epoxy sticks to pretty much anything and adding 3 times the work is not an awesome idea if it can be avoided at minimal cost.
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  #11  
Old 07-05-2011, 02:39 PM
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TeddyDiver TeddyDiver is offline
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Where in Finland you are Frasco? I've got my holidays after one week and I'll be around in the south. Might have a look and MHO if you want to..
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  #12  
Old 07-05-2011, 03:02 PM
frasco frasco is offline
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The boat is located in Loviisa and you're welcome to drop by if you find the time. In which case you should probably time your arrival to the 16-17.7 when there's the Small Ship's Race festival.
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Old 07-05-2011, 03:17 PM
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TeddyDiver TeddyDiver is offline
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A bit early, still on the road then.Going to have some sailing on inland lakes first. Maybe a week later. PM send..
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  #14  
Old 07-10-2011, 10:22 AM
Aharon Aharon is offline
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One Tonner

Quote:
Originally Posted by gonzo View Post
... I used to race an IOR onetonner in the late 70's.
Nice boat. "IOR Onetonner"... I looked it up. Wikipedia says it corresponds usually to 40'=1Ton. The original poster however mentioned a loa of 23'. Is this boat lighter than 1 ton?
Beautiful dog too!

Last edited by Aharon : 07-10-2011 at 10:24 AM. Reason: sudden realization
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  #15  
Old 07-22-2011, 03:12 PM
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TeddyDiver TeddyDiver is offline
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Frasco! Check your PM folder..
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