About to order Epoxy/Fiberglass- How much is enough?

[DocTide]

I am about to purchase the epoxy and mat this weekend. I was wondering how much would be enough. I am just building a casting deck- I have 3/4th marine grade wood in a 48x24in sheet, will be cut to about 40x24in. I plan to coat it with epoxy then a single layer of fiberglass. Approximately how much resin/hardener would I need? I was probably going to purchase from us composites in the 4 to 1 Fast hardener since I am here in Ft Lauderdale the temp is rarely below 80F. I was also planning on patching together a small floor addon for a CC- but that can come later.

So a few questions- is this the direction you would go? The standing platform is not going to be permanently mounted on the boat, so should I consider other methods? Perhaps a penetrating solution and a paint sealant instead? Is the 4 to 1 Fast a good idea? Any cheaper alternatives in terms of sourcing the epoxies? Any help is really appreciated. I can supply pics of my project if needed to get a better understanding.

Thanks

 

[52FordF2]

I have a 19 footer and on my 5th pail of five gallons of polyresin.

But your just doing a deck. If your using Epoxy and not Poly remember to paint it or cover it somehow. Epoxy does not do well with UV.
Casting deck should be less than a gallon. Doing both sides?

The other more knowledgable "Smarter" Guru's should be showing up soon.

 

[Woodonglass]

Yeah, Is there a reason you're using the expensive epoxy and not the Poly? You stated mat. You don't use mat with Epoxy. You just use Glass fabric. Pics would be helpful. Glass comes by the yard and usually either 36 or 50 inches wide. You can figure out your measurements and order accordingly. You'll need to coat the wood first and then soak the mat too but as stated a gallon of either of the products should be ample. There is also Vinyl Ester resin which is kind of the middle ground between the two. Do some Googling and you'll learn a lot about the differences.

Personally, I'd use the 435 Poly from USC and a layer of 1708 biax. You may need some cabosil to do some filleting around the edges etc...

 

[ondarvr]

Why would go with the fast hardener when it's your first time doing this and the temps are high?

Skip penetrating stuff.

And like already mentioned, no mat with epoxy.

 

[gm280]

Knowing what little I know, I would also go with the polyester 435 resin and the 1708 material. And if you only are doing such a small piece, one gallon would be plenty. JMHO!

 

[DocTide]

Sorry for using term mat, I meant fabric. This is not my first time working with fiberglass/resins. I have previously made 4 surfboards (totally different I know).

Having read around, and since this will NOT be permanent on the boat (I will take it out when I put in storage) is it really necessary to glass the wood? If I do go with poly (which seems logical to save costs) is there a penetrating solution I should use before glassing?

Thanks for the quick responses!

 

[ondarvr]

Again, skip all penetrating products, they are almost worthless.

All you need to do is buy a good grade of plywood and paint it, if you don't keep it in the boat it will last for decades. Applying epoxy before the paint will allow to hold up a little better, especially outside.

 

[Woodonglass]

I Totally agree with this ^^^. If you're going to be removing it and NOT storing outside in the elements then paint it with Rusoleum Oil paint. Thin the first coat 50% with Mineral Spirits to get good penetration and then follow with 2-3 full coats and it will last for decades!!!! If you Really pay attention to the edges and soak them well it will last even longer. If you want to to go a bit further down the preservation road you could use this... and just use plain polyurethane since you'll be painting the wood you don't need the UV protection of the Spar urethane. This sealer will keep the wood from rotting even if it's left out in the elements. You should only need a quart of this to do what you're doing.

 

[DocTide]

Excellent, Thanks!

Now before I let this thread die, I might aswell ask opinions on how to setup my CC properly. The boat has 1" wood fiberglassed in for me to mount the CC. My CC is just hollow aluminum tubing and am worried that when I bolt down into the 1" wood, the weight on the CC legs might drive the bolt down through the bottom hull. I am planning on making the legs of the CC a location for a cooler seat. I attached an image showing vaguely my idea. Any ideas how to properly mount this part?

 

[TruckDrivingFool]

Trying to understand your CC question, How are the bolts attaching to the 1"floor? Just threaded like a lag bolt? If it's just through bolted I wouldn't worry about it driving them down If the CC collapsed they should just kinda hang there.

Got any pics of your mounting point in the boat and the CC? If so post them up and perhaps we could brainstorm a mounting plan that would ease your fears.

 

[DocTide]

I will get some pics up tonight. But essentially, yes- I was planning on grinding down the pointed tip of something like a lag bolt and screwing that into the wooden panels for the CC. My worry was that since I plan to put a cooler and seat on top of the hollow alumnium legs, if the weight gets too heavy, the tubing might bend forcing the bolts to drive a little farther down. I had planned on putting some wood (like that of a wooden broom handle) into the legs to help prevent this. Attached is the actual CC I am using:



The legs at the bottom are hollow, and have 2 mounting holes on each side. I planned to add a piece of starboard over the top and bolting through the mounting holes and starboard creating a flat surface for my cooler. Does I am worried about going to heavy/deep. I considered putting wood inside the tube to stop it from "potentially bending" I have also through about putting wood on the sides and mounting the starboard to that.

 

[TruckDrivingFool]

Your idea to give some inner support sounds solid to me and I really don't see the bolts/studs being forced down if anything if you bolt through both I'd think they (the bolts) would just stay put and give the appearance of loosening up.

Instead of grinding studs save some work and look for studscrews

or just use lag bolts from the start.

With that said I have never seen a CC up close in person let alone have much of an idea how a factory mounted CC is mounted and this fact gives me reservations about how long only an inch of wood will handle the forces you will put on it as you hang on and sway and bounce in rough water. In my mind it would be better if you could at least get a backer of some sort to increase the gripping thickness.

Double with that said it'll really help to see some pics of what you're working with.

 

[DocTide]

Here are some pics, sorry it took so long:

This shows the legs, and the wooden pieces fiberglassed into the boat floor for mounting.

This is my idea to use the legs as a mount for a platform/cooler place:

My new idea is to just buy some 1.5x1.5in wood, fiberglass it, and use it as a brace under the boards platform which would help with the hollow legs from potentially collapsing. Does this make sense?

The the boat is small where I wont be using it in rough water, and dont plan on using it as something to holdon to while underway too much. A backing wouldnt hurt if someone can give me ideas that might help.

 

[Woodonglass]

Why don't you insert some wood dowels into the aluminum legs to keep them from collapsing. You could soak em in some wood sealer so they wouldn't rot and they'll last a good long time. Then use some supplemental pipe clamps like these for additional support.

 

[DocTide]

That sounds good. The dowels are what I mentioned above but was still somewhat concerned. I do think those pipe secure downs would help tremendously!

 

[gm280]

I guess I'm the dummy here because I don't see those tubes collapsing with normal usage. What I would do though is insert something into the ends to keep out any foreign materials out be it water or insects. Those open ends look like excellent places for dirt-dobbers or bees ( of all types) to take up residency. JMHO!

 

[DocTide]

They might not collapse. But since there will be a cooler, and seat resting on them- I want to make sure they dont! The weight of a person, cooler, ice, beer, etc. I was just concerned about. Also, I was concerned that IF they did start bending downwards, that the screw/bolt holding them in place might drive through the wood and puncture the bottom of the boat since it is just a fiberglass floor (no foam or wood).

Woodnglass: Is there a product I can buy at a store nearby to soak the dowels in? Also where can I find those clamps if you can link? I can only seem to find PVC ones online for a 1-1/2in tube.

Thanks

 

[Woodonglass]

I make my own sealer using this formula... 1 part Boiled Linseed Oil, 2 part Mineral Spirits, 1 Part Polyurethane Finish. Works Really Well. Soak the wood till it won't absorb any more (about 15-30 mins) then wipe off the excess. Let it dry then apply 2-3 coats of full strength Polyurethane. Wood will never absorb water!!! You should be able to get those clamps at any electrical supply house. Standard fair for electrical conduit installations. If not you can order online here...http://www.elecdirect.com/product/ca...inch-rigid-imc