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lenm

Ocracoke 20 in OZ

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Using neat, pigmented epoxy as a primer is as costly as a good primer, plus it's a lot harder to fair and smooth. When you put pigments in epoxy, you don't get a paint like finish, as it's generally translucent, not the solid color paint produces. Of course, multiple coats can get you a solid color, but this is even more work and materials. Naturally, it can't be done as a top coat, as the epoxy will still burn with UV exposure, just more slowly then a straight neat coat. Lastly, the thing with primer is it makes a uniform "tie coat" for the top coat and can change the look of the top coat as well. For example if you paint a red over grey primer, it'll look warmer then if it was painted over a white or black primer. I'd much prefer to work primer than a neat epoxy coat, FWIW.

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That looks so nice.  Great job on the fairing.

 

I have to agree with PAR on the high build, I would much rather sand primer than epoxy.  I suppose the only purpose of high build is to fill scratches and other minor imperfections anyway, so if you can get your surface to 150 grit without it, there's nothing wrong with skipping it.  No getting around the finish primer though.

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20 hours ago, Riggs said:

It does look rather good sir :)   I bet it was hard attaching it to the deckhead like that though but it made the painting easier i am sure

Thanks Riggs, probably not long before you overtake me :-)

If you do, please take some pics of your flip/turnover, I've been stressing over this step given confined space.

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12 hours ago, PAR said:

Using neat, pigmented epoxy as a primer is as costly as a good primer, plus it's a lot harder to fair and smooth. When you put pigments in epoxy, you don't get a paint like finish, as it's generally translucent, not the solid color paint produces. Of course, multiple coats can get you a solid color, but this is even more work and materials. Naturally, it can't be done as a top coat, as the epoxy will still burn with UV exposure, just more slowly then a straight neat coat. Lastly, the thing with primer is it makes a uniform "tie coat" for the top coat and can change the look of the top coat as well. For example if you paint a red over grey primer, it'll look warmer then if it was painted over a white or black primer. I'd much prefer to work primer than a neat epoxy coat, FWIW.

 

Thanks Paul and Steve for your thoughts.

I probably haven't been so wise/cost efficient with my finishing.

I had a very mottled surface after sanding through the blue trowel able fairing compound - exposing the fibreglass/timber colour in several spots.

Maybe I should have gone over these bare spots again with some more blue before sealing it with the neat epoxy.

It would have created a more even base colour to start with.

Not sure how many coats you would expect required to cover the mottled base.

I am up to 4 coats and only at about 80% opacity so far.

It is a white coloured water based epoxy primer.

If the pigmented epoxy option is as translucent as you say it is - I'm now glad I didn't go there !

 

 

 

 

 

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This is what 3 or 4 applications of pigmented epoxy can look like.  But I did cheat, threw in some microspheres to bump the opacity in a couple layers.  Not so much to affect the compression numbers but enough to reduce transparency.  Convenience of white.20180412_174613.thumb.jpg.3cc0fda5b7bcde7ee166fc8afd37d5fd.jpg

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If really interested in using pigmented epoxy, this is what I've learned. I use this technique inside lockers and buoyancy tanks, where getting paint once the decks or seat tops go on, is very difficult or nearly impossible to do neatly. Epoxy formulators all suggest about 5% pigment by weight. This is because the epoxy starts to dramatically lose physical properties, once much over this amount. Given pigmented epoxy is used to avoid paint in difficult to paint areas or places that will never see paint again, you can safely go to 10%, with a slight decrease in tension modulus, compression, etc. Once over, this properties drop quickly, for example at 20% you've lost over 50% of the epoxies elongation, peel strength, etc. I've used 15% with good results inside of buoyancy chambers and lockers, where painting is just too difficult once the boat is sealed up. I have an anchor locker that wouldn't be too bad to paint if necessary, because the hatch is fairly big, but it's 15% pigmented epoxy coating is doing just fine and only took two coats to get full, solid coverage, much like if it was painted.

 

Now, if you suggest these numbers to the epoxy formulators they'll balk, spouting off numbers and figures about stuff, you might not fully understand. This said, if you keep the mix below 20% (by weight), you'll be fine if, all you want is a tough colored coating, rather than paint. The anchor locker I mentioned gets beat up a lot, as you'd imagine, but other than some fluke scratches, it's still doing fine after a decade.

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Had some fun flipping the boat today..

After an attempt to rollover her over under the shelter I decided to abort (too confined).

The backup plan was to put her on castors and roll her out of the shelter, perform a 90 degree turn then traverse down a narrow sloping section of my yard to reach a point where a crane could collect and flip.

What a tight squeeze - I got stuck coming out of the shed and also sheared two castors off the jig when we got bogged, however the remainder went relatively smoothly.

I'm glad I didn't end up building an OC 24 or 256 as these would have been a ship in a bottle literally due to their size.

My neighbour (school teacher) told me one of her students told her that they saw a boat 'flying' over her house on the way in to school this morning.

 

 

 

 

Resized_20180708_153319_456.jpeg

crane.jpg

flip.jpg

return.jpg

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That looks a whole heap easier than my go around.  Good to see it right side up :) Now the fun starts

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Been a while since an update

The last couple of months have been filleting and laminating the inside of hull.

 

IMG_20180907_112155.jpg

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I saw that picture and shuddered. After it's all done your mind will block the misery quickly, so there is that! :rolleyes:

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Thanks for easing the pain. Working with messy epoxy goo in confined spaces is not fun..

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A friend lent me some commercial moulds for making some deck hatches. He has never used nor remembers how they work..

Please can anyone offer any suggestions

Am I correct in assuming they are a female mould for the water channel/ gutter?

Mostly, I can't figure out what the recesses are on the outer sides.

IMG_20181004_123519.jpg

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I cant figure it out but as a gutter it is too shallow . The gutter would be at least 1" deep and 1" wide  with pockets for the water drain fitting 

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Thanks Lotus,

I checked and it does measure 1"x1".

I think the photo is a bit deceptive as the moulds are very large as far as a hatch goes. 

No drain fittings though as you mention.

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At first I thought the recesses were for hinge knuckle clearance, then realized they are going the wrong way.  Maybe just layup your parts on the mould without them.

 

You can easily add a block to the corner of the mould to create a space for a drain fitting.  Block of wood, a little clay...

 

As far as glassing the interior, I just can't understand how it takes so long.  I stood back thinking I could probably do 3 a day when I was starting.  I sure got a reality check once the process started.  My dad was over when I was doing some of this and his first comment after getting through with one box was, "I can't believe it took that long".

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Thanks Steve, the clay is a good idea. 

 Re glassing interior - was thinking the same - a little difficult to put a time frame on things.

I'm trying to knock one over each day when I get home from work.

IMG_20181006_144136.jpg

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