The dirty work begins

[jee70611]

How many gallons of resin do y'all think I'll need to replace the stringers and frames in this boat? It's an 18ft 1989 Sunbird Eurosport II. The stringers look to be 12 inches tall. My question is how would y'all suggest to replace these stringers? I was considering just sketching it all out with measurements and taking them all out and building the new substructure as one piece then putting it in and glassing it up. The only thing stopping me from doing that is I'm concerned that the hull will warp or twist and hurt performance. If you look inside the hull at the bow tip there is the lift point they used at the factory. I was thinking I could just lift up on it there and that would help hold the shape true, but I'm reluctant to do it without a few opinions first. Should I just do one side first or do y'all think it would be ok to just cut them all out and rebuild it as a unit ? Any suggestions are appreciated. <br />Here is a link to the pictures. The ones dated 4-24-03 and 4-26-03 are the most revealing of the substructure. <br /><br />Boat Pics <br /><br />Thanks<br /><br />James

 

[JasonJ]

Re: The dirty work begins

For some reason the pics for my project are not working anymore, but I am doing a similar project. You can read all my posts about the project, look for my name or "Project Skanky Beast", it outlines my progress to date.

 

[Solittle]

Re: The dirty work begins

James - Read Jason's posts carefully.<br /><br />I wouldn't use the lifting eye up front. That will tend to bow the sides. Building a substructure is a way but I would think that you would take a risk of not getting a good fit. I would do it stringer at a time. How is the transom?

 

[JasonB]

Re: The dirty work begins

If it helps, I just re-did, the transom, knees, floor, and 3 stringers in my 15' Glastron. 0ne stringer was 9'x7" and the other 2 were 9'x4". I used 4 or 5 gallons of poly resin.

 

[jee70611]

Re: The dirty work begins

Thanks guys. SoLittle, the transom is ok I think. I'm not sure yet. I hope I don't have to redo it too, but if it is bad it's comin' out. I tapped on it with a hammer all around and the tone barely changes in some spots. For that reason, I'm not sure if it is rotten or if it's just different thicknesses of glass. I plan on taking the drill and drilling some little holes on the inside close to the floor as that is where I believe the most vulnerable spot is. The boat had sat with water almost up to the crank long enough to leave a rust line on the flywheel. When I do start on the stringers, what would be the best wood to use? I was thinking of just using some pressure treated 3/4 Pine plywood. Would that be ok? The lumber yard guy said that if it was treated to like .4 it would likely last for years. I just don't know hardly anything about lumber. It looks like they just slopped it together. The longest stringers are spliced up towards the bow. I don't want to resplice it, but rather use full length wood if possible. Any more suggestions?<br /><br />Thanks,<br /><br />James

 

[BillP]

Re: The dirty work begins

Without knowing what fabric you are using it is a total WAG (as in Wild Axx Guess). Here's some numbers to calculate your useage.<br /><br />1 gallon of resin will typically wet out:<br /><br />1.5 oz mat = 32 sq ft<br />18 oz woven roving = 40 sq ft<br />24 oz woven roving = 32 sq ft<br /><br />Those are the fabrics I use for this type project.

 

[jee70611]

Re: The dirty work begins

I'll be using West System epoxy resin so I can't use the mat. I'll probrably use a couple of layers of cloth and maybe some roving around the bottom edges. This is my first time doing this. Does that sound like an ok way to do it? <br /><br />James

 

[Solittle]

Re: The dirty work begins

jee - You need to look at alternatives for the wood. Resin & glass do not adhere especially well to pressure treated wood due to the "stuff" they use in treating the wood. Pine also does not necessarily have a good reputation for use on or below decks. Go to the search function at the top of the page and try different search arguements to see what others have done.

 

[Bgriffin67]

Re: The dirty work begins

I'm working on a 18' Sunbird 195 myself. I can REALLY relate to the pictures. Mine looks about the same except my stringers were made of plywood. All that was left was fiberglass shell around where the stringers were before they rotted to nothing.<br /><br />I'm using pressure treated 2x8x12 lumber to replace the stringers. I am also coating them with 2 more coats of water proofing (yeah right) before putting them in. The deck will be treated to the same. <br /><br />From what I understand if your using the West System (damm big $$) I think you want the untreated lumber so that the epoxy will soak into the wood. Not really sure on that but that is how the other wood penetrating resins seem to work. <br /><br />By the way have you figured out how to get the transom shield off? I'm getting ready to pull the deck, engine, stern drive from mine just as soon as I finish building the A-Frames to lift them. I think I'm going to have to do the Transom on mine. From the cross section I can get to in the transom shield area it is just like foam. I'll know more when I can look in there. Folks around this area say all the Sunbirds have transom problems, but will have to check it out.<br /><br />If you don't have it get a copy of Runabout Renovation by Jim Anderson. He goes into the floor,stringer,transom replacements. Unfortunately he doesn't write a word about IO only Outboards so we get to do some educated guessing with Transom replacement.<br /><br /> My Project Sunbird

 

[BillP]

Re: The dirty work begins

You cannot use the same mat as polyester but there is mat available for epoxy. The difference is poly mat has a chemical binding that desolves only in poly resin...but doesn't desolve with epoxy. Epoxy mat is stitched and had no binding to desolve. <br /><br />The first time you try to wrap 18oz woven roving over the top of a 2x stringer you will find out why mat is preferred. Nothing is easier (not even close)than mat for hand laminating. Otherwise, mechanical fasteners help keep woven roving down. <br /><br />About pressure treating...modern pressure treating is not the same as the old stuff made from petroleum. Epoxy res will stick to it without any problems...so well that it peels the ply layer before letting go from the wood. You DO need to air dry the wood first. Suggested method is to coat the wood with thinned epoxy before laminating.<br /><br />Southern yellow pine is an excellent wood for boat decks and hulls but is hard to find clear. It has plenty of resin (pine tar)to keep rot and bugs out. Many older boats were made of Dade County pine back in the 20s, 30s & 40s. The problem now is you pay big bucks IF you can find it. Very good to build with but not practical anymore.

 

[JasonJ]

Re: The dirty work begins

I cut and laid all my stringers in, and affixed them to each other by the cross frames. I then glassed them in one by one, working from the outside in. I monitored the hull trueness dure the entire process. Since my bare shell of a hull sat for about two months, it had made its way back to its true shape from the waprs it had from all the lack of structure and pressure from the trailer rollers. I am doing my project on my trailer, and it is working for me, but your project may go differently, so be carefull. I have used about 6 1/2 gallons or poly resin so far, and that has glassed in my transom and six stringers, two of which are 3"x9', 7"x11', and 10 1/2"x 12'.

 

[jee70611]

Re: The dirty work begins

Thanks for all the info guys. Even if it takes me a while to reply I still appreciate any and all help y'all give . BGriffin67 and JasonJ I've been following your posts also. I still need to clean it out some more and finish cutting the floor out. I also gotta get rid of all that old foam and pressure wash the boat to get any grease off of it. I just found out today that my stringers were made of plywood also. BGriffin67, when you say transom shield are you talking about the fiberglass around the top of the transom near the edge of the swim platform or the engine's transom assembly? I may not have gotten that far into it yet. BillP, I'm glad you told me they make mat for epoxy. I was wanting to use it 'til someone else said that the binder wouldn't dissolve. Where do you think the best place to get some would be? Anywhere online? Yeah the west system is pretty expensive, but it is really easy to use and doesn't have that horrible smell. It costs me at $89.00 for a gallon of resin and the equivalent hardener at the local Boater's World. I'm trying to do this boat at like $100 to $200 bucks at a time so it'll be a while before I start glassing. I plan on replacing the transom first if it needs it. I'm pretty sure the entire wood structure is rotted out because it sat for a while with water almost up to the crank.

 

[Bgriffin67]

Re: The dirty work begins

The transom shield I'm refering to is the OMC part that goes through the actual transom that the gimble assembly and sterndrive mount to on one side and the engine on the other. <br /><br />I don't have my engine out yet so its kinda hard to see, but I think it is just a few bolts once you have the engine and sterndrive off. <br /><br />One other thing that has been concerning me is the engine bed (the fiberglass engine mounts). Sure doesn't look all that strong, but with me swapping out the floor I'll have to do something with it.

 

[BillP]

Re: The dirty work begins

Epoxy mat can be had at uscomposites in West Palm, Florida. I don't think advertising links are allowed here so that is almost the address.