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Discussion Starter · #1 ·
I repaired my polyester keel bottom (a 1973 Pearson 30 ) with an epoxy resin and glass patch. (about a square foot). During the patch work I sanded off the gelcoat for the patch down to the original fiberglass. I left about 1 inch of gelcoat around the patch which I’ve de-waxed with Interlux 202. I’ve used AeroMarine 300/11 Epoxy Resin Adhesive, which I was told was waterproof, to wet my glass patches. Nonetheless I’m about to apply Interlux Interprotect 2000e as the outside bottom layer , just to be sure of a waterproof bottom.
A few questions.
1) Generally speaking am I on the right track ?

I read in Interlux literature that an undercoat of epoxy resin should be used prior to the application of the 2000e barrier coat.
2) Assuming I was correctly told the AeroMarine 300/11 is water proof does it properly substitute for Interlux Epiglass in this ?

I am concerned about the “interface” between the old and the new. As the epoxy is sticking well to the old de-waxed gelcoat in my tests my thought is to epoxy over the inch border of gelcoat and then paint over this with the 2000e, thus making a waterproof boarder and seal around the painted patch.
3) Am I right in doing it this way ?
4) How waterproof is 2000e generally ? It seems mostly used over gelcoat. Is it enough here or should I consider using gelcoat on top of the patch and then paint ? I’ve read that gelcoat can stick to epoxy.
 

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Chastened
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You're using an epoxy brand that I'm unfamiliar with. Many folks use West Systems epoxy.

Still, if your sources are correct about the waterproofing, you'll be fine. Secondary bonds between epoxy and polyester or vinylester are very strong, stronger in fact than new poly over old poly.

You're on the right track.
 

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One of None
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Do yourself a favor don't even try mess with gelcoat mixing/applying Epoxy is nearly always the best way to repair FG. 2000E is epoxy and you don't have to use another under it. Epoxy doesn't stick.. it chemically bonds,is near impossible to remove from FG Also, don't use silica for fairing filler it's like trying sand granite! Use a soft fairing compound it's tan, some others make it in purple.
 

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I repaired my polyester keel bottom (a 1973 Pearson 30 ) with an epoxy resin and glass patch. (about a square foot). During the patch work I sanded off the gelcoat for the patch down to the original fiberglass. I left about 1 inch of gelcoat around the patch which I’ve de-waxed with Interlux 202. I’ve used AeroMarine 300/11 Epoxy Resin Adhesive, which I was told was waterproof, to wet my glass patches. Nonetheless I’m about to apply Interlux Interprotect 2000e as the outside bottom layer , just to be sure of a waterproof bottom.
A few questions.
1) Generally speaking am I on the right track ?

I read in Interlux literature that an undercoat of epoxy resin should be used prior to the application of the 2000e barrier coat.
2) Assuming I was correctly told the AeroMarine 300/11 is water proof does it properly substitute for Interlux Epiglass in this ?

I am concerned about the “interface” between the old and the new. As the epoxy is sticking well to the old de-waxed gelcoat in my tests my thought is to epoxy over the inch border of gelcoat and then paint over this with the 2000e, thus making a waterproof boarder and seal around the painted patch.
3) Am I right in doing it this way ?
4) How waterproof is 2000e generally ? It seems mostly used over gelcoat. Is it enough here or should I consider using gelcoat on top of the patch and then paint ? I’ve read that gelcoat can stick to epoxy.
If the bottom-of-the-keel repair was in the aft section of the keel bottom - the hollow area that is 'behind' the ballast section - be sure to lay up extra heavy cloth/roving. Breaking of this area of the keel on a P30 happens when the boat is improperly blocked when on the hard. What you NEED to protect here is the encapsulated iron keel that's inside the front and middle-bottom of that keel --- MUST be waterproof and Water-VAPOR proof.

For P30s the rear/aft block under the keel should be placed no further aft than an imaginary vertical line from where the aft part of the keel joins the hull. If the keel is blocked at its very aft end you will ultimately break that hollow section of the trailing section keel AND/OR cause the hull to radically deform when the boat is 'blocked' on the hard .... large deformed 'oil canned' portions of the hull in the area of the seat locker near the companionway and the bottom of the 'ice box'. Also note the use of Vee-poppit jackstands between the prop and the rudder and at the bow. You need to 'stretch out' the hull of a floppy P30 a wee bit when 'blocking' one. Also leave the backstay/forestay 'tight' when blocking to help prevent the 'hogging/sagging' when blocked



1. You are on the 'right track', make the repair lay-up extra strong / thick as per above.
2. and unqualified yes
4. Interlux 2000e is generally quite waterproof ... but in the past their recomendations of thickness have gradually increased substantially over time to prevent water permeability through into gelcoat and matting layers .... I'd increase the final thickness recommended, as Ive had problems with permeation with a P30 when using 2000e, ditto with any barrier coat.

Dont worry about the gelcoat, just provide plenty of 'tooth' by coarse sanding with 40 grit, etc. before putting on any epoxy or barrier coat. Dont reapply any gelcoat below the waterline, especially if you are epoxy coating or applying barrier coat - as its solely 'cosmetic', and so is the matting layer which is used to 'cushion' the gelcoat. "Best" is to grind off all underwater gelcoat and simply cover with epoxy/barrier, then bottom paint.

If this boat is on or near the Chesapeake, whats the production number of this P30?
 

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Discussion Starter · #5 ·
Boat is up on Long Island Sound.
I’ve only had her 14 years; should I be ashamed to tell you I don’t know her production number or even how to find it ? :>)
Many thanks for your help here, and everyone who answered; made a big difference in my comfort level doing this job. Of course it may be a few years till I can be sure it worked as well as I hope; how I wish there was a method easier than drilling to determine levels of water saturation in a hull. All I read of water meters suggests they are of little use in keels of this nature.
 

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If you plan on putting bottom paint over the 2000e Use the thumbprint test to ensure the best adhesion. If you can leave a print in the 2000e without any of it coming off it's ready for bottom paint. If it's a good drying day..you should be able to paint in an hour +/-

I just stripped my lead keel down to bare metal and applied 8 coats of 2000e and 2 coats of micron extra...I never want to have to do that again.
 

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Bombay Explorer 44
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If you plan on putting bottom paint over the 2000e Use the thumbprint test to ensure the best adhesion. If you can leave a print in the 2000e without any of it coming off it's ready for bottom paint. If it's a good drying day..you should be able to paint in an hour +/-

I just stripped my lead keel down to bare metal and applied 8 coats of 2000e and 2 coats of micron extra...I never want to have to do that again.
Why so many coats of epoxy? Over iron or steel or even grp I can understand but over lead?

Surely you just needed a primer coat? Or am I missing something?
 
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