Cored Hulls

[captchuck]

So I have spent all winter mulling over whether or not I should put lifting rails on my 26' seaway while the deck is up for new tanks. Here is what I am left with, the hull is cored and I have access to through bolt all parts of the rails if I put them on. However in some areas it is a serious stretch and therefore I would still be able to through bolt them but not hollow out the core from the back etc. So i guess my question is is hollowing out the core a must? is 5200ing everything and using 1/4" hardware enough to keep it water tight since they will be submerged? Are there any other options? (i have looked into smart rails)

 

[F/V First Team]

save yourself headaches down the road, de-core the areas and do it properly. Toss a fender washer down in the hole, thru-bolt the rails on, zip off any bolt that is proud of the inner laminate, fill with hull & deck, glass over.

Bazinga

 

[tashmoo2]

I fully agree on removing the core now. Would also use epoxy and mix with a high density filler. I cored through hull fittings 30 year ago using polyester resin with thickeng filler and replaced it 20 years ago with epoxy.

Polyester with filler is like glass. It cracked like glass from normal impact running in a decent sea. Water followed the cracks to the balsa. I would mix some chopped strands with the filler if you use polyester or get advice from a builder

 

[tunaorlater]

If you can't decore it from inside do it from outside and thru bolt it. You must decore it though.

 

[MouseTrap]

I fully agree on removing the core now... or get advice from a builder

He just did

save yourself headaches down the road, de-core the areas and do it properly. Toss a fender washer down in the hole, thru-bolt the rails on, zip off any bolt that is proud of the inner laminate, fill with hull & deck, glass over.

Bazinga

 

[Blitzen]

I have bonded wood rails to the bottom of a glass hull with MAS Epoxy FlexBond 5000 and no fastners and it hasn't let go yet, fast easy simple and no holes in the hull. Plexus would work too.

 

[F/V First Team]

He just did

I was going to say that exact same thing after lunch, but I decided to go grind some 30 year old fiberglass instead

 

[captchuck]

Plexus/ mas bond

I have bonded wood rails to the bottom of a glass hull with MAS Epoxy FlexBond 5000 and no fastners and it hasn't let go yet, fast easy simple and no holes in the hull. Plexus would work too.

I looked briefly at the plexus can anyone else attest it's strength or the flex bond I plan on using the 1258 r rails from Hamilton marine. Their PVC. I could also perhaps just go with the adhesive only where I can't reach from the inside

 

[F/V First Team]

It is possible to use plexus only with the pvc rails, however you need man-power, good prep and jack stands galore to hold everything in place. You might be able to use those 2" wide ratchet straps for cargo, just wrap them around the entire boat. I've seen it done with split rails, never with a full length rail (split rails are foolish, just fyi). Once it is in place, let it cure. And don't miss, plexus isn't as forgiving as Rule 300

 

[captchuck]

Lexus

It is possible to use plexus only with the pvc rails, however you need man-power, good prep and jack stands galore to hold everything in place. You might be able to use those 2" wide ratchet straps for cargo, just wrap them around the entire boat. I've seen it done with split rails, never with a full length rail (split rails are foolish, just fyi). Once it is in place, let it cure. And don't miss, plexus isn't as forgiving as Rule 300

Do you think one is better than the other or more cost efficient etc

 

[F/V First Team]

Are we talking sealant/adhesive or methods to hold the rail in place (jack stands/straps)

If it was my boat I would mount the rails where I wanted them with screws (really easy to do, just drill and countersink the rail material then drive a #14 self tapping square drive into the hull), remove the rail, drill through with a 1/4" bit, go on the interior of the hull with a 1-1/2" hole saw and cut through the interior laminate, pop out the plug with a screwdriver (5/16" common works well with about a 6-8" shank), clean up the hole really nice and vacuum the debris out, put blue tape over the holes on the exterior and hot coat the holes on the inside, I might even put two layers of mat in the holes just to get a really nice seal and new surface for the fasteners, drill the 1/4" holes for the fasteners and with the aid of a helper thru-bolt the rails back in place with some machine screws, bedding them into Rule 300 clear sealant. Have a 1-1/4" fender washer on the inside along with a locknut. Trim any excess threads off and fill the void with putty. Make fair and glass over the holes. Easy peasy.

 

[tashmoo2]

F/V first team and Mouse trap,

Ok so what do you fill the holes with? Thickened epoxy or thickened polyester resin? I oversize holes now (following diagram in WEST manual)and fill with thickened epoxy because of a bad experience with polyester resin in bottom of hull. I would have never noticed if I wasn't replacing the rudder stuffing box.

I removed rudder box last month to replace rudder and there was no cracking.

 

[F/V First Team]

Hull and deck putty, epoxy isn't my favorite thing, chances are your boat is polyester, so why put something else in/on it? Like making a pizza and dumping on tomato soup instead of tomato sauce, same basic thing, totally different flavor.

Gelcoat with some cabosil/micro balloons/etc would work well too, just kick it light so it doesn't exotherm (sounds like what you might have found digging around your rudder box)

 

[WC1966]

"Hull and deck putty, epoxy isn't my favorite thing, chances are your boat is polyester, so why put something else in/on it?"

How do I tell what the builder used in a 1966 Webbers Cove 34 foot hull?
I do suspect that then Vinalester was not invented at that time. I have used West system epoxy to fill the hole left when removing unused thru-hull fittings.

 

[F/V First Team]

anything before 2000 is probably laid up with 100% polyester resin
anything before 1985 probably has woven roving and mat as their layup schedule

vinylester resins gained popularity in the last decade, and in a few places earlier on, for skin coats and fuel tanks. as far as epoxy is concerned, unless it is a boat built out of plywood and impregnated then glassed over with a layer of 10oz cloth or some other special laminate, you wont really see it much in hulls. exceptions being usually klevlar and/or carbon composities for specialty craft.

 

[captchuck]

Rule 300

Are we talking sealant/adhesive or methods to hold the rail in place (jack stands/straps)

If it was my boat I would mount the rails where I wanted them with screws (really easy to do, just drill and countersink the rail material then drive a #14 self tapping square drive into the hull), remove the rail, drill through with a 1/4" bit, go on the interior of the hull with a 1-1/2" hole saw and cut through the interior laminate, pop out the plug with a screwdriver (5/16" common works well with about a 6-8" shank), clean up the hole really nice and vacuum the debris out, put blue tape over the holes on the exterior and hot coat the holes on the inside, I might even put two layers of mat in the holes just to get a really nice seal and new surface for the fasteners, drill the 1/4" holes for the fasteners and with the aid of a helper thru-bolt the rails back in place with some machine screws, bedding them into Rule 300 clear sealant. Have a 1-1/4" fender washer on the inside along with a locknut. Trim any excess threads off and fill the void with putty. Make fair and glass over the holes. Easy peasy.

Thanks for the details! Is there a difference between rule 300 and 5200? And would you put the 300 between the rail and the hull everywhere else?

 

[F/V First Team]

rule 300 is clear, sets up quick but not fast, if you get some on you, no big deal you can just let it set up a few minutes and take it off. works that way on clothes too, just let it set up and peel it off. comes out of the tube nice, stays where you put it with in reason. dont expect half the tube to stay in a 2 inch spot, gravity wont allow it. put it all along the length of rail you are putting on, working 6-8 feet at a time if its in your comfort level, shorter if not. just cover your holes as you go and dont have any bare spots and you will be golden. cleaning the adhesive afterwards is simple, a jack knife slid along the hull and rail, pull the cured rule off.

bazinga

5200 is a mess waiting to happen

 

[Montauk Rocket]

F/v first team, thanks for sharing your knowledge and experience so freely and in-depth. Really appreciated.

 

[Eastporter]

Ditto- You're a good guy to share all your "trade secrets". Thanks and have a good weekend to all the DE lovers of America!

 

[F/V First Team]

The common sense items are free, I have to charge for the "trade secrets"