O.K. you f/g experts, I need some help.
 

As some of you may recall, I ripped a piece of skin off the bottom of my 23 last fall.It's about 16" wide by 20 feet long right down to the roving.It's finally warmed up enough to get to this and I'll take pics once I get it off the trailer.
My question is, what do I order to repair this?
First, what weight mat do I need?
Poly or epoxy? The guys at the boat yard insist poly because that is what they used originally. I'm kinda leaning toward epoxy because it's a big area and the epoxy gives you more time before it kicks. But, I don't want any incompatability issues.
Between layers, do I need to layup within a certain time period with either system - or will I need to sand and wipe between?
Your favorite source to order from would help too.
Thanks,
Bill

Re: O.K. you f/g experts, I need some help.
 

Epoxy has the strongest bonding properties out of all the resins and it's totally water resistant (unlike polyester). Polyester is great for laying up inside a mold, but repairs below the water line should be done with epoxy.

Re: O.K. you f/g experts, I need some help.
 

I totally agree with using epoxy. BUT you will have to Paint the bottom instead of re gel coating it. You should buy those little booklets from West Marine regarding repair work from The West System. I would also want to roll the boat over on it’s side to help gravity get the epoxy and glass to lay down properly. On a job like this vacuum bagging might be a good way to go. As for which glass to use for me I would rather use a few layers of glass instead of one thick woven rovin layer. There is a boat down here in the shop with this same type problem. Good luck and remember lots of Beer.
FellowShip [img]/images/graemlins/wink.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

Actually there are 2 epoxy resign's that can be gellcoated over. Ringleader did it to the stem of his boat using WEST System. I saw the boat 3yrs latter and it's flawless. I have never done it.

The other epoxy resign is made by System 3.
http://www.systemthree.com/p_sb_112.asp

Recommended Uses:
It was especially formulated for use in building and repairing sail and surfboards over polystyrene cores. It can also be used for coating and laminating. SB-112 is unique in that polyester resins and gel coats may be bonded to it without the use of "tie-coats". We recommend that polyester be bonded onto freshly sanded SB-112 epoxy within 48 hours of cure.

Re: O.K. you f/g experts, I need some help.
 

Thanks guys - Epoxy it is.I won't be gelcoating anyway, barrier coat and bottom paint.I plan on laying it on it's side as much as I can and I will be doing multiple layers.
I'll try to get some pics.

Bill

Re: O.K. you f/g experts, I need some help.
 

I agree with everyone - epoxy is the only way. There are tons of sources. Do a google and I'm sure you'll fine one close to you. A trick I learned on my last boat build will save you alot of finishing time and you could probably get away with leaving the boat rightside up. If you don't vacum bag, this may work. Find a thin flexable board (luan ply or masonite) and make it non-stick. Layup your patch work in reverse (finish layer down first)on the board and secure it to the work area. You might need to use small tap screws or wedge it up in place. The idea is the non-stick surface of the board makes a smoother finish, thus less finish sanding and holds the patch in place. Good luck!

Re: O.K. you f/g experts, I need some help.
 

I have done the board trick, but be sure it is nonstick before glassing! Use wax paper in between the board and glass. At least that is what I have done and it works as long as you are careful. If all else fails, I have thickened some epoxy with micro balloons to get the layers to hang upside down. I only thickened enough to get them to stick, but still permeate through the glass for bonding issues. This is how all the guys glass the bottoms of wooden boats to avoid the swelling sequence. I have done 5 or 6 boats that way and they are still looking great after at least 6 seasons of full service. I am going to do this to my wooden skiff this next winter. Good Luck!

Re: O.K. you f/g experts, I need some help.
 

A piece of visqeen [plastic sheeting] work's very well. It will peel off, no problem.

Re: O.K. you f/g experts, I need some help.
 

Billybob-

Polyester resin will work fine (since your boat was originally made with it)but epoxy is known to have better secondary bonding characteristics so if you don't mind shelling out some extra $$$$, go with the epoxy. As far as glass is concerned, I would order 1.5oz mat and 1808 biaxial...which is much easier to wet out than the 24oz woven roven that your boat was made with. I would start out with a piece of 1.5 oz mat that is smaller than repair area and than go with a slighlty larger piece of 1808 and then keep repeating the process of using gradually bigger pieces until damaged area is covered.

Re: O.K. you f/g experts, I need some help.
 

A few questions:

As always, I humbly defer to your experiences, but there were two things mentioned that I thought were " no-no's":

o using micro balloons for water proof/underwater applications ( better to use cabosil ?)

o using mat with epoxy - I thought mat was not good w/ epoxy, and cloth was preferred ?

I just need this clarified for my info.... Thx.

Re: O.K. you f/g experts, I need some help.
 

I wasn't going to get involved in this one with poly vs epoxy but
Honestly I would talk with a few more professionals, in the yards and suppliers, and get their advice first ... I dont think this is something anyone would want to do twice !!!

I've not heard about the glass spheres or microballons not being able to be used U/W ....Thats a common fairing material that can be mixed with other agents to make suitable fairing compounds... Cabosil is more "structural" and a bitch to fair. Again with talk of a barrier coat you are good to go.

Mat... I have always always been told that fiberglass mat, which is what I would use as the first layer against the damage area, Chemically and Physically bonds with the poly based resins. There is a chemical reaction between the mat and poly that creates chemical interlinking and bonding …. I think I would definitely want that in your situation. That first layer is going to hold everything together. The understanding I have is that this is not true with epoxy. Depending on how much you need to build up the suggestion is a layer of mat then structural glass( like the 1808) mat then glass. (You can also buy the glass with the mat already stitched in to the 1808 )

Look into Vinylesters ( higher grade polys and even Iso resin) as they are more water resistant ....plus if your doing a barrier coat your protecting it anyway. We all know that they are compatible with your hull...so there is no guessing

Joe Merton would be a good individual to call ... www.mertons.com he's great to deal with and in Springfield, Ma. and better yet is a SeaCraft admirer.

Re: O.K. you f/g experts, I need some help.
 

Wow, thanks for all the advice, knew I could count on ya's.
What I think I know is that chopped mat is held together with some type of binder which reacts with the poly but is hard to wet out with epoxy.But they make a stitched mat just for epoxy that doesn't have the binder.
So, I was thinking of using that and cloth in layers.I am a little concerned about the whole mess sagging on me while I wait for it to set.I have used plastic sheet before as a release film so I'll have to figure out what I can do to support it.I guess I'll go with the thicker epoxy too, that should help some. Vacuum bagging is beyond me.
I also think you need apply your subsequent layers during the time between initial gel stage and full cure or you'll be sanding good between layers.
So, I'll keep you posted.
It's a really bizarre thing, I've never seen this happen to a boat before.

Re: O.K. you f/g experts, I need some help.
 

18 stand's for 18oz per sqyd. The 08 stand's for 3/4oz per sqft.
A sqyd of 1808 weigh's 24 3/4oz.

That's what 1808 is. If you want Biaxle without mat a common number is 1700.

The use of extra mat with epoxy is a waste of good epoxy. the binder's don't relax right and it will eat up a ton of resign.
Mat is used to get good contact with the last layer laid. Like with the heavy Roven Woven's to fill the void's between the stranding.

1808 is available in +45/-45 and 0/90. This is the way the strands run. To maxumize strength you want to alternate the strand orentation.
You can cut the +45/-45 on a 45deg angle and lay it so it's 0/90. It's a little wastful with the material, but if the area is not so big and all you have is the +45/-45 it work's.

Mat is used for bulking the laminate up too. If you want to bulk it up, then why not add someting that has a whole bunch more strength. Like another layer of 1808. [img]/images/graemlins/wink.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

So, if mat provides more harm/waste than good, what the benefit of using 1808 with epoxy as opposed to just going with a heavy cloth?

I though I almost had this glassing stuff figured out, until I heard the mat/epoxy incompatibility thing. [img]/images/graemlins/confused.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

Compatibility is a kind of wide open term. Epoxy will work with mat. It work's better with Polyester resign.

I think my point here is I don't like to see epoxy used with
1 1/2oz or heavier mat.

With the fact that epoxy doesn't break down the binders in mat, it makes it harder to conform to tight radius's

Re: O.K. you f/g experts, I need some help.
 

I agree with some of the above but definitely know that mat gets a bad rap.

Next time you are looking at some of the modern boats....ask to see a core sample. Not much mat, but a lot of spray core and core mat. Why? Resin is expensive and mat is very labor intensive. Spray core is cheap and easy to apply...and same goes for core mat.

Enough said unless we want to start debating over who makes the the best t-tops...New Englanders or Floridians?? [img]/images/graemlins/cool.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

A PICTURE IS WORTH A 1,000 WORDS.

http://www.legnosboat.com/lbiproducts/fiberglass.html

FELLOW-SHIP [img]/images/graemlins/cool.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

I hope your not buying from that place. Those prices are way high.
1808 Biaxial 50" 18 oz (0 degree x 90 degree) /.75 oz mat

1 Yd. Pkg. 1808-1 $14.70


Fgci is about $9.00per yd for the same thing. Their site is down again.

Re: O.K. you f/g experts, I need some help.
 

Ha Warthog
No, I finished my boat I just felt like a few pictures might help.
FellowShip [img]/images/graemlins/cool.gif[/img]

Re: O.K. you f/g experts, I need some help.
 

Thanks for the Mertons link Scott, that's close enough to drive to and actually feel the stuff.
I thought I'd put up a few pics even though it's still on the trailer.

Here's the view from the transom:

http://img.photobucket.com/albums/v6...r/P1010002.jpg
.
A side view:

http://img.photobucket.com/albums/v6...r/P1010005.jpg
.
Closer view:

http://img.photobucket.com/albums/v6...r/P1010003.jpg
.
Look at the delamination at the forward end! I know I'm gonna have to grind back til it's a good bond.It's quite a mess, huh?

Re: O.K. you f/g experts, I need some help.
 

UG! That's not good, but it's not the end of the world.

Vacuum Bagging is the way to fix that baby. Stll with the long run it will be a pain.

Re: O.K. you f/g experts, I need some help.
 

Joe is a great guy to deal with … he will get you back in the water. And his pricing looks to be real reasonable when compared to that other dealer in Fellowships link. Wow they are expensive.

As far as your photos …. Yikes and yikes again !!! That one above is one ugly looking picture .

Did anyone ever tell you how that may have occurred ??

Re: O.K. you f/g experts, I need some help.
 

Billybob;
I have been watching this thread with great interest. You have been given some good advice in general but the one thing that seems to be missing is the root cause of the problem. In all my years of boat building and repair we would allways try to discover the cause and extent of the damage before making a plan for repair. Blindly slapping a layer of glass on a delaminated section of hull may or maynot fix the problem. Unfortunately your pictures are not quite good enough to really make an educated guess but what they might show is 2 possible causes of your problem. One is that at some time in your boats history it sustained a severe impact in the area of the damage and caused what is known as interlaminate shear. Which is a delamination of the glass layers. And second ( please don't flame me for this) poor lamination from the builder. If what I see in the pictures is the glass looking very dry and whiteish on the strake then one of these is most likely the cause of your problem. If it was me doing this job the first thing I would do is try to get the area preped back to a solid laminate and then you will really know the size and extent of your work ahead.
Bill

Re: O.K. you f/g experts, I need some help.
 

Well Bill, you're right I will have to grind back til I get to a good bond and I'm just hoping it doesn't go much further.You can see I will have to go forward and up a ways anyway.
As for the cause? Have a seat and grab a beer:
It was a fall evening and the blues had been hammerin the bunker at Bpt harbor all week, so I headed out of Milford in a hurry to snag some bunker before it got dark.It was real choppy and I was going faster than I normally would because I was alone.I heard a thump, stopped and saw something bobbing in my prop wash, tilted up the motor, just a few scratches, figured I hit a floating log, and went and fished.
I pulled the boat out the next day cause I was borrowing a slip and that's when I realized what happened.
I took it to Norwalk Cove Marina which is a big yard but the manager is a friend of a friend.He looked at it and told me that at his rates, he would total the boat - I really didn't want that.One of his guys says "I remember that boat, I painted it a few years ago".Seems a guy had the boat hull painted and repowered then a few weeks later he brought it back with some serious bottom damage but noone remembers what specifically happened.Their opinion was that it was a "Friday Boat" with an original layup problem - but who knows, and it took close to 30 years to show?
Anyway, the guy took the new power off and sold it to a guy who used to work at the boatyard. This guy repaired it and sold it to a guy who was going to restore it.This guy ended up restoring a diesal inboard instead and my hull sat in his yard for a few years until I bought it.
So, who knows?
You love these old Seacrafts and all the history that goes along with them, but this one has a little more history than I would like [img]/images/graemlins/frown.gif[/img]
But Bill you're right, the surface has this whitish look and doesn't look like there was any adhesion there.Original layup or bad repair, I don't know.Don't know the circumstances of the first damage either.I wish I had gone back to get the piece that ripped off, too.
So, I'm left with a bit of a job on my hands.

Bill