1708 mat for stringers

cterrebonne · #1 05-28-2012, 05:33 PM

Looking to start tearing into the V20. Would one layer of 1708 mesh over the stringers would be enough? Or should I do two layers? I am open to ideas. I will being going with epoxy resin.

tartuffe · #2 05-28-2012, 05:58 PM

The 1708 is primarily used with polyester resins. The mat sucks up so much resin that is makes for a good waterproofer but it is not as strong as the biax. The problem is that it sucks up so much resin.

When you use epoxy, it is a much better waterproofer ounce for ounce versus polyester so you do not need the mat. Straight 17 oz. biax will be sufficient but personally I am using 2 layers. I like overkill when it comes to my boat. The wood is your structure. The cloth seals the wood. I only go with 2 layers for the purpose of added protection against rubbing over time.

I like US Composites for epoxy and boat builder central for mat.

cterrebonne · #3 05-28-2012, 08:53 PM

Quote:

Originally Posted by tartuffe

The 1708 is primarily used with polyester resins. The mat sucks up so much resin that is makes for a good waterproofer but it is not as strong as the biax. The problem is that it sucks up so much resin.

When you use epoxy, it is a much better waterproofer ounce for ounce versus polyester so you do not need the mat. Straight 17 oz. biax will be sufficient but personally I am using 2 layers. I like overkill when it comes to my boat. The wood is your structure. The cloth seals the wood. I only go with 2 layers for the purpose of added protection against rubbing over time.

I like US Composites for epoxy and boat builder central for mat.

thanks for the info. I was going to use epoxy usa for the resin. Have you heard any negatives about their product?

Also I am looking at the mat. 17 oz 45/45 or 0/90 I see that one mas the chopped strand attached to it is the 45/45.

tartuffe · #4 05-29-2012, 11:21 AM

I am not familiar with epoxy USA. That doesn't mean its not as good, I just liked US Composites pricing. I want to say it is around $340 with shipping to NC for a 7.5 gal kit. It comes in 1 gallon containers. You'll want to start with at least 7 gallons so if their prices at that quantity match up then I would go for it. You'll also want the slowest cure available. I was fortunate that most of my big layups took place when it was 40 degrees outside so that gave me the time to work for several hours on a single batch. Now that it has warmed up I am having to mix smaller batches and it is more challenging.

I like the 45/45 and was advised that is the way to go from the fellas on boat design.net.

Here is another tip that I have learned, MEK costs more than acetone per gallon but you save overall because it does not evaporate nearly as quickly but still quickly

cterrebonne · #5 05-29-2012, 10:51 PM

thanks for the tips. The epoxy I saw was about 500 for 7.5 gals. It said that it was a no blush formula. I didn't see if the US comp stuff was low/no blush. No big deal if it blushes some simple green can take care of that between coats. The US comp stuff is looking better on price.

What repairs you made that used up 7.5 gallons?

Shrek · #6 05-30-2012, 12:23 PM

I'm really thrilled to see that you're going to get cracking on the V. I'm really looking forward to seeing your progress on the old girl.

tartuffe · #7 05-30-2012, 03:48 PM

The U.S. Composites is non blushing if you use their slowest hardener. The middle and quick cure are both blushing.

I'm up to 17 gallons used at this point. The transom used up a good portion. I left about a 2" gap between the wood core and gunnels/hull all the way around the transom to be sure to get it packed full of PB. In hindsight I could have gotten by with a thumbs width. That would have resulted in 2.7 gallons less epoxy. I also used a large amount on the stringers. I bedded those in PB rather than use the foam. That would have saved another 1.25 gallons. Same with the front bulkhead. Also used around 1 gallon used on fairing compound. If you don't need any fairing then you can eliminate that as well.

Oh yeah, I wasted about a gallon when I got ahead of myself and it kicked off so all told I'm up to around 5 gallons of over expense, or education whichever term you prefer.

At this point for new transom, stringers, bulkheads, reinforcement, and floors for storage compartments I'm up to 5 sheets of 3/4 marine grade fir. 21 gallons of epoxy and 50 yards of 17 oz mat at 50" width. Around 2.5 gallons of 1/4 chopped strand, 4 gallons of cabosil, and 1 BILLION 4.5" 24 grit sanding disks. My boat was toast.

Do not add up the costs. Just start it and build as you can afford. As you probably know, working on the boat is half the fun!

cterrebonne · #8 05-30-2012, 10:11 PM

Quote:

Originally Posted by Shrek

I'm really thrilled to see that you're going to get cracking on the V. I'm really looking forward to seeing your progress on the old girl.

Thanks man, I am thrilled too. It is tough not having a boat to go fishing, lol. I still need to check out your new boat. From the pictures it looks like one sweet rig.

cterrebonne · #9 05-30-2012, 10:14 PM

Quote:

Originally Posted by tartuffe

The U.S. Composites is non blushing if you use their slowest hardener. The middle and quick cure are both blushing.

I'm up to 17 gallons used at this point. The transom used up a good portion. I left about a 2" gap between the wood core and gunnels/hull all the way around the transom to be sure to get it packed full of PB. In hindsight I could have gotten by with a thumbs width. That would have resulted in 2.7 gallons less epoxy. I also used a large amount on the stringers. I bedded those in PB rather than use the foam. That would have saved another 1.25 gallons. Same with the front bulkhead. Also used around 1 gallon used on fairing compound. If you don't need any fairing then you can eliminate that as well.

Oh yeah, I wasted about a gallon when I got ahead of myself and it kicked off so all told I'm up to around 5 gallons of over expense, or education whichever term you prefer.

At this point for new transom, stringers, bulkheads, reinforcement, and floors for storage compartments I'm up to 5 sheets of 3/4 marine grade fir. 21 gallons of epoxy and 50 yards of 17 oz mat at 50" width. Around 2.5 gallons of 1/4 chopped strand, 4 gallons of cabosil, and 1 BILLION 4.5" 24 grit sanding disks. My boat was toast.

Do not add up the costs. Just start it and build as you can afford. As you probably know, working on the boat is half the fun!

Sounds like your hull needed some work. Mine is in really good shape. Just the transom and the stringers are probably needing to be redone towards the transom area.

Did you separate the liners on your boat? I am thinking about just cutting the floor out and then reglassing it back in and sanding all the old wellcraft factory non skid off and putting down some duraback or some gatorhyde.

cterrebonne · #10 06-07-2012, 09:31 PM

hate to bring up an old thread, but I have an epoxy question. From what I have read, if the epoxy does not blush then you can put another coat right over the first one with out sanding? Similar to polyester resin with out wax in it?

I know epoxy is stronger but I made the mistake by calling my local fiberglass repair shop and he said just to use poly. He said if I was worried about water seeping in to just paint it or gel it after? Poly is like half the price, Decisions decisions. I might just split the difference and go with vinylester