How many layers?

[Wingedwheel]

OK after finding my transom was bad, I got further and further into my boat and discovered that everything made of wood was rotted. Its not a big boat (17') and I shouldn't have too much problem replacing everything. My question is, when I do the glass-work, whats standard for layers? How many do I put on when I cover the wood? Thanks

 

[bigredinohio]

Re: How many layers?

I used 9 oz. cloth and epoxy to encapsulate my wood prior to install. I made sure that I painted the wood three times with epoxy and added the fiberglass on the third coat. I found that 9 oz. was a good size to give strength without being too heavy.

 

[clockwatcher]

Re: How many layers?

Are using poly or epoxy?
What are you using for your core material?
How fast does the boat go?
Inboard or outboard?
How thick is the hull?
How thick is the glass on the stringers now?

 

[Wingedwheel]

Re: How many layers?

Clockwatcher, I'll probably use epoxy resin, Core material will be AB plywood,Its an outboard with a 115 HP rating and I run an 85hp Merc. The boat will do about 40 mph. When you ask about thickness do I need to mic it to find out? Thats why I'm asking these questions. I know what I need to put on the wood, just not how much. Thanks.

 

[bigredinohio]

Re: How many layers?

I used 9 oz. cloth and epoxy to encapsulate my wood prior to install. I made sure that I painted the wood three times with epoxy and added the fiberglass on the third coat. I found that 9 oz. was a good size to give strength without being too heavy.

I should clarify my answer so not to confuse. The above was my way to "waterproof" my wood prior to gluing it in. After being installed, it depended upon what the piece was. Transom included tabbing with cloth and multiple layers of 1708. Stringer was only two layers of 9 oz. since it was really a deck support.

 

[clockwatcher]

Re: How many layers?

I asked your question a lot before I started and never got a straight answer. The most common sense approach I heard was to build it back as you found it, but do it correctly leaving no way for water to get into your core. If you're going with epoxy and biax cloth, you can go with less thickness than with poly.

Have you taken a look at Bateau2, Boat Builders Central? I followed their advice. Basically marine ply, epoxy and biax cloth. They start by tabbing stringers with 3 layers of 6" x 12 oz. biax tape offsetting each layer by one inch. Actually, they use this layup on anything attached to the hull. Then cap the stringers with one or two layers of 17 oz. or 1708 if you really want to use some epoxy. I used this method. It took time and material but the boat feels rock solid now and I don't even have the floor/sole on yet.

If you haven't yet purchased your glass, they have good stuff and decent prices and will give you and accurate schedule with your dimensions.

 

[Wingedwheel]

Re: How many layers?

Thanks guys. This is the first time I've undertaken something this in-depth with fiberglass and anything I can learn is helpful. Clockwatcher, I haven't purchased anything yet as I'm still stripping out the rot. I originally started on the transom when it was obvious it was bad and as I moved forward I found more and more until I finally pulled the cap off and found it was a total gut and restore. Its a bass boat and I got it for a good price last year so I feel I'm justified restoring the hull. I couldn't believe the shabby job that was done from the factory as far as the little things that were not done to insure this would not happen. The boat is a Stinger and was built in Tenn in 1980. The company went out of business after 8 years and perhaps this is one of the reasons. The style and layout is very nice and I like the boat and I'm sure most of this happened because of an engine upgrade sometime after it was manufactured. Obviously whoever put the larger engine on did a crappy job of sealing the factory mount holes and this has been getting wet for some time. I have to make my own patterns as the wood is either completly rotted away or wet mush. I'm taking pics, but I have to figure out how to reduce the size so I can post them. Clockwatcher, I read your thread and I have to say it was pretty inspiring and educational. I hope mine turns out as well as yours did.

 

[Wingedwheel]

Re: How many layers?

OK here are a few pics of the project as I started untill now. I have the hull half-way cleaned out

 

[Wingedwheel]

Re: How many layers?

Here's the main hull and floor. You can see where the previous owner added a piece to try and beef it up. Think he knew about it??

 

[Wingedwheel]

Re: How many layers?

Another view. He had covered the floor with another piece of ply and new carpet. I had no idea it was soft. A big lesson learned!

 

[clockwatcher]

Re: How many layers?

You've got a job ahead of you. One good thing is the boat is low on the trailer and shallow. The materials won't be much.

How's the motor?

 

[Wingedwheel]

Re: How many layers?

I went through the motor last year and replaced fuel lines, rebuilt the carbs, new wires and plugs. This spring I replaced the shift cam, cam follower and shift-shaft coupler. The engine is in great shape. I live on a lake and its tough not having my fishing boat. I do have a 19' SeaRay though and I'll make do with it if I can get it away from the wife and kids.

 

[Lukiebs]

Re: How many layers?

Now might be a stupid question but how long between coats of epoxy and between layers of glass??

 

[clockwatcher]

Re: How many layers?

Now might be a stupid question but how long between coats of epoxy and between layers of glass??

The resin will soak in the cloth and it will become transparent within a minute or two. Any air between the surface and the glass needs to worked out, then the next layer is applied while the first is still wet. You want to have all your glass cut and rolled up ready to go before you start mixing the resin. At least that's how I did it. To get the air out some people use rollers, others use a squeegee, I just dabbed it with the brush. There's video out on Youtube that shows how this is done.

Also, you'll get the resin on your gloves, so climbing in and out of the boat while doing this can make a mess.

 

[Wingedwheel]

Re: How many layers?

Clockwatcher, you're right about the boat being low and easy to reach inside. Once I finish the tear-out(hopefully this weekend if the rain holds off) I'll only have to climb in to do the two center stringers. after that I should be able to reach everything from the sides. Darn I'm excited to get moving on this..

 

[dude11]

Re: How many layers?

Just a short note on posting pics.--try resizing them to 600x450--then they really load and look alot better.dude11

 

[Greg Mrozinski]

Re: How many layers?

Wingedwheel,

Nice looking project you have there. If you are using epoxy resin then you will not need too much glass. Nothing against Clockwatcher but three tabs of 1208 plus a cap of 1708 is A LOT of glass. Way more than what probably came in your boat oringinally. They probably used a little CSM and then threw down some 16 oz woven roving. Using one layer of CSM with one layer of 1708 will be plenty. 1708 is very strong stuff and should handle your 17' bass boat just fine. I recommend a good grade exterior ply for the stringers and transom and bed them down good with PL premium or a PB mix.

Just as a reference I am in the middle of a rebuild of a 17' fiberglass runabout. I replaced everything. I used a poly resin with 2 oz CSM and 1708 on everything with good overlap between the stringers. Floor was coated with CSM on the bottom. Top was tabbed in with 1708 then coated with CSM. All I can say is it will take a nuclear bomb to tear that boat apart now.

My whole point being if you choose the right glass you can get away with less. Good luck and have fun.

 

[Fisherball]

Re: How many layers?

Nice project!

 

[Wingedwheel]

Re: How many layers?

Thanks guys. Greg your right about what was there. I've figured that out as I tore everything apart. I'm almost done with the tear-out as I had a good day today. Tomorrow theres a chance of rain and if not I should be done and hopefully take a wire wheel to everything and get it nice and clean. The transom boards are cut and sized and I'm going to put a coat of resin on them tomorrow. I'll need to pick up some more plywood tomorrow for my runners and bracing and if I'm stuck inside due to rain, I'll cut parts.

 

[Wingedwheel]

Re: How many layers?

Well it was a good day. No rain and I got the hull prepped. I'm a little itchy, but happy that the teardown is done. I guess its uphill from here.