Grinding hull for new stringers

[ondarvr]

You said you will be applying fairing compound, any fairing compound will need to be sanded smooth prior to painting, and you may need to apply fairing compound a few times to get it right. Depending on the paint it may require a primer first.

This is where gel coat saves a huge amount of time and money for a floor, no prep needed, apply right over the laminate with or without a non skid additive and roll to achieve the texture desired....done.

 

[proshadetree]

Yep ondarvr I like your thinking. Easier and cheaper than most alternatives.

 

[kcassells]

Yep ondarvr I like your thinking. Easier and cheaper than most alternatives.

He is the da MAN!

 

[Woodonglass]

Are you saying you're going to paint the stringers below deck?? Polyester resin cure rate is dependent on several factors. Temp, amount hardener used. Typically if temps are 70 or above it could be painted within 24 hours IF you put wax in the last coat. Why would you use Epoxy Fairing for Polyester resin? No real benefit. You can make a great fairing compoun using Poly and Micro Baloons. What are you using the Fairing Material on?

 

[ondarvr]

You say that you can use 1708 or 6 oz on the stringers....which would you say is best?

!708 works well, 6oz cloth is almost worthless for stringers and transoms.

 

[ImJohnnyKelley]

Are you saying you're going to paint the stringers below deck?? Polyester resin cure rate is dependent on several factors. Temp, amount hardener used. Typically if temps are 70 or above it could be painted within 24 hours IF you put wax in the last coat. Why would you use Epoxy Fairing for Polyester resin? No real benefit. You can make a great fairing compoun using Poly and Micro Baloons. What are you using the Fairing Material on?

I am not painting the stringers. I am painting the deck. I agree that it may be easier to use gelcoat, but the deck and walls are all connected and getting the color and finish right on the walls with brush or spray gelcoat is not easy. I plan on painting over the resin on the deck, walls and gunwales, then applying SeaDek to the deck so paint should be fine under the SeaDek. Just wondered how long I would need to wait to prime and paint.

I know I can make my own fairing material, but I have 2 gallons of the TotalBoat Epoxy fairing already sitting here, and would hate to waste all that. I will be fairing the deck smooth before paint and the transition between the old walls and new deck that I am installing. Trying to get it smooth and as close to original as I can.

 

[Woodonglass]

Well If you use Epoxy then you'll probably need to go the Paint route. Celcoat doesn't adhere well to epoxy.

 

[ondarvr]

SeaDek can be nice on the feet and the uncovered areas on a bikini clad body. Make sure the paint you use bonds well and can hold up under the SeaDek, the SeaDek is dependent on the paint's bond to say in place.

 

[ImJohnnyKelley]

SeaDek can be nice on the feet and the uncovered areas on a bikini clad body. Make sure the paint you use bonds well and can hold up under the SeaDek, the SeaDek is dependent on the paint's bond to say in place.

I have been doing some research on catalyzed paints and some one part wet edge deck paints. Seems they have a pretty strong adhesion rate. I looked into Line-X for the whole interior too. They have marine grade stuff now and a company in Sarasota does some beautiful work. But it is out of my price range, so SeaDek it is. Haha.

 

[ImJohnnyKelley]

Today was a good day on the boat (other than killing an angle grinder while using a cutting wheel). Got the rest of the main fiberglass skin and the balsa core up from the main deck.

​

Started cutting out sections of the plywood subfloor. Not a bit of glass on any of it. Actually accidentally dropped a screwdriver and it went straight through to the handle. Stuff is much.....at least in the back. The front is definitely wet, but not rotted out yet. Took some work to take out what I did. The foam under it is soaking. Boat has been out of water and under cover or in building for months....yet I can squeeze out water like it is a ripe lemon. Insane. But at least it is coming up fairly easily. Think it will take a full day to finish removing the ply and all the foam at this rate.




Had a couple question to ask now. Gonna be putting in glassed ply for the deck, but the one I am removing used balsa core to lift it up everywhere leaving a one inch drain trough around the edge at the base of the wall. Gonna do the same I think, but was wondering if there was a better product than balsa to use? Looked at foam core as well. Any help or advice would help. Also I was hoping to keep the casting deck, but closer I get to it the more I realize I need to replace the stuff under there too. Hoped it was dry up there, but it aint. Here is a pic of the deck right now:



I like the deck and I like the storage/fish box in it. Don't think I have the ability to build one that looks as good. Here is my idea....tell me if it is crazy or doable. It looks like the only real support for it is the stringers going under the fish box. I was thinking I could cut it out with a cutting disc cleanly, pull it out in one piece, fix under it, and then glass it back in. Does that seem doable or am I crazy? What would I need to do to make that work? What is the best way to go about it in your opinion? Thanks for all the help guys and for following along!

 

[tpenfield]

You could cut the top of the casting deck out and replace the core. I see lots of sailboat decks and cockpit floors repaired that way. You could use plywood or a high density foam sheet as the new core.

Keep in mind that the floor/deck for this boat appears to have been originally part of the cockpit liner, not part of the hull. You are sort of using a 'hybrid' approach of 'old' and 'new' construction techniques in your repair process.

What are the sidewalls of the cockpit attached to? How much space is between the cockpit sidewall and the outer hull ? I believe, based on your pictures the sidewalls used to be attached to the cockpit floor, which had the balsa core. All that was resting on top of the plywood of the stringer grid, which is part of the hull.

 

[Shakedownscott]

Looking really nice Johnny, you are making good headway on the demolition. You can cut out the casting deck and re-install it in one piece. I would cut it where it would be easiest to blend the seem when done.

On the project boat I am rebuilding, I had to cut out the casting platform too. Its not back together yet, but I am planning on using a strip of 3/8" plywood behind the seem to hold it straight while I glass the topside.

 

[ImJohnnyKelley]

You could cut the top of the casting deck out and replace the core. I see lots of sailboat decks and cockpit floors repaired that way. You could use plywood or a high density foam sheet as the new core.

Keep in mind that the floor/deck for this boat appears to have been originally part of the cockpit liner, not part of the hull. You are sort of using a 'hybrid' approach of 'old' and 'new' construction techniques in your repair process.

What are the sidewalls of the cockpit attached to? How much space is between the cockpit sidewall and the outer hull ? I believe, based on your pictures the sidewalls used to be attached to the cockpit floor, which had the balsa core. All that was resting on top of the plywood of the stringer grid, which is part of the hull.

Yes the side walls were attached to the fiberglass and balsa core deck and all that was resting on the plywood and stringers below. I am wanting to try and do the same I think. The sidewall has nothing behind it. Just a few inches of air and then the hull. I am contemplating just not using the ply at all and raising the stringer height by an inch and just using nida core or something like that run directly into the sidewall. Would save a lot of weight and money, but not sure if it is strong enough or stiff enough for what I need. The weight would be on the stringers so not sure if it would be an issue. Probably just end up doing exactly what they did because it worked for the last 35 years. I could probably get away with a thinner ply under the core if I use nida instead of balsa because of the strength.

 

[tpenfield]

I think the challenge will be where the floor meets the sidewall, as you will have access to only the outside surfaces and not behind the sidewall.

 

[ImJohnnyKelley]

I think the challenge will be where the floor meets the sidewall, as you will have access to only the outside surfaces and not behind the sidewall.

I agree. Not sure what the best plan is for that.....other than lots of resin and glass. Feathering higher up the wall in layers, then fairing the living daylights out of it afterwards. I can also go with a more structural foam under it to take the stress off of it. Just trying to get ideas on it and the casting deck up front too.

 

[ImJohnnyKelley]

So I haven't done much on the boat. We are in the process of buying a new house and that has taken over my time. But on the plus side, the new house is on 12 acres and has a pole barn for me to work on the boat from. All open air so no smell issues from he poly! Anyways, had a couple questions I wanted to find out from you all. Has any of you ever used the Prisma foam stringer system? Seems like a very interesting thing. Not really considering it at the moment, but was wondering what peoples thoughts were on it.

Speaking of stringers, I was trying to figure out what foam to put under the stringers before bedding them down so I don't get hot spots on the hull. I am planning on using seadek for the flooring, so I got them to send me a sample pack. They included about 30 squares of 1/4" thick, 2" square closed cell foam. I have picked my color, so now I am gonna use the samples for the pad. Has 3m adhesive on the back to hold it in place while I put the bedding compound down. Seems like a good way to recycle to me!

 

[JASinIL2006]

Those Prisma pieces look interesting, but expensive. How much would it cost to use them vs. conventional construction?

 

[Woodonglass]

That will work fine.

 

[ImJohnnyKelley]

Those Prisma pieces look interesting, but expensive. How much would it cost to use them vs. conventional construction?

I don't have the exact number, but I believe I could do it for less than $500. I only have 2 stringers and 3 bulkheads. Just saves a ton of weight and more importantly a ton of time. Just looks cool. Not sure if it is a real option, but a cool thought.

 

[Woodonglass]

Well conventional stringers will run you less than 1/2 that cost. Time savings would not be that much IMHO due to still needing to prep the hull properly and then glass in the Prisma Stringers. :noidea: