fiberglass repair

[88olympic]

I have an 18' fiberglass boat and there was a repair done just under the drain plug by the previous owner. It finally gave away by cracking and I started picking at it and maybe a cup of water came out along with the Marine tex that was used to repair it. It looks like there was a small block that they laid the fiberglass over and now it is missing or maybe just a pocket of air. I have a small (1" ) hole I can use to fill the space up which is about 2" in three directions ( I shoved a rod up and found the end of the space I am working with). I was going to use Bondo fiberglass filler with fiberglass hair in it but it cures too fast and hard to squeeze in there. Then I thought that Marine tex would be the best way to go, but again it aitn't going to be easy. Now I am wondering about 5200, it would be easy to fill the hole and I would be laying a couple of layers of glass on it anyway and then try my luck with gel coat. Do you think 5200 could be used for this type of repair? Thanks for any replies. Mark

 

[Triton II]

Re: fiberglass repair

88olympic, have a look at oops's thread, it covers everything you need to know about FG repairs.

http://forums.iboats.com/showthread.php?t=234392

Cheers mate,

TII

 

[metriccrescentwrench]

Re: fiberglass repair

A photo would help, but if it's anything like what I'm visualizing I don't think 5200 is the way to go.

IF it's like the picture in my feeble little mind I'd make a slurry of epoxy resin and milled fibers, thicken it with cabosil up to a peanut butter consistency and use that to fill the void. First you'll need to get that entire area dry and clean, then scuff it up with some sandpaper so the repair can bond to it, then vacuum off the debris from sanding. Paint a LIGHT coat of epoxy resin over the area, then add the slurry.

If you want to try gelcoating it afterwards read this:

http://www.cruisersforum.com/forums/f55/will-gelcoat-adhere-to-epoxy-5794.html


edit to add: You could use polyester resin instead of epoxy (which would have the advantage of there being no question that gelcoat would adhere, but polyester resins aren't very good at secondary bonds (bonding to already cured fiberglass) whereas epoxy is very good for that. There's a lot better chance that the epoxy will be permanent and not come loose like the marine-tex repair did.

 

[metriccrescentwrench]

Re: fiberglass repair

Sounds to me like you have a rotted transom in which case a bandaid (just patching the hole) isn't going to help.

Good point, I haven't had enough coffee yet this morning and should have thought of that.

Yes, before going forward with a patch a little investigating needs to be done. 88 - get some photos of that and post them so we can take a look at what's going on.

 

[88olympic]

Re: fiberglass repair



I hope I put the pics in right. I poked all around and the transom and it is solid. This patch has been there since 1997 and I check it all the time, never before has there been a crack only the last time I took it out. I did beach it at a lake and the wind picked up pretty good so I think that is when it happened.

 

[88olympic]

Re: fiberglass repair

you can't get to it from the other side. It is like a small void maybe 2'' x 3" right at the back of the boat. It is under the drain hole which is the very lowest point of the hull inside and all around inside it looks like new.

 

[Woodonglass]

Re: fiberglass repair

Does this hole go all the way thru the transom?

 

[Yacht Dr.]

Re: fiberglass repair

What I would do at this point is to grind out all the damaged glass and grind/prep for your glass that your planning on doing anyways .. then take some pics and postem up ..

You may have to remove the drain for the repair.

No to the 5200 question .. yes to filling it with poly/cabosi/ chop strand putty ( as long as its not through the hull ). Then lamination of glass wrapping up on your transom.

YD.

 

[88olympic]

Re: fiberglass repair

ya, I guess it does. It sort of goes up about 1 " and then it is above the hull fiberglass and then goes fwd and port and stbd. about 2". It is like there was an air pocket when they formed the hull. It is about 1/4" to 3/8" thick in all directions. Kinda hard to explain. The transom is probably about 3" thick.

 

[Yacht Dr.]

Re: fiberglass repair

Thats why Im saying.. clean it up ready for glassing. Cant tell a whole lot right now when your looking at a repair thats not even been explored yet ..

YD.

 

[88olympic]

Re: fiberglass repair

No, outboard. The Dr. is right, I'll clean it up and fill with polyester with long strand fiberglass. The can says it is waterproof and it is used on boats. I'll just keep ramming it in there till the void is filled, then sand and prep for a couple of layers of cloth then gel coat. Thanks everybody. Mark

 

[jbcurt00]

Re: fiberglass repair

No, outboard. The Dr. is right, I'll clean it up and fill with polyester with long strand fiberglass. The can says it is waterproof and it is used on boats. I'll just keep ramming it in there till the void is filled, then sand and prep for a couple of layers of cloth then gel coat. Thanks everybody. Mark

I'm not sure that's what YD was suggesting. I read his previous posts & this:

Thats why Im saying.. clean it up ready for glassing. Cant tell a whole lot right now when your looking at a repair thats not even been explored yet ..YD.

As a suggestion to more fully probe the area via prepping it for a fiberglass repair you will at some point have to complete regardless of how the patch is completed. By cleaning it up & removing some additional material, you'll be better able to assess the damage and be able to post pix that will be more easily assessed. And AFTER that be able to perform the repair as needed. NOT to fill in the area after 'cleaning' it up.

If this damage penetrates thru the transom into a 'void' beyond. You can shine a light thru the hole & see into the boats bilge? This repair may warrant exploration from the interior, which would require removal of some portion of the interior deck. Else, as some have suggested, your repair/patch won't be sufficient or permanent.

YD will swing thru & let you know if I am assessing his advice incorrectly.

 

[Yacht Dr.]

Re: fiberglass repair

Spot on jbcurt !

What I would do at this point is to grind out all the damaged glass and grind/prep for your glass that your planning on doing anyways .. then take some pics and postem up ..

You may have to remove the drain for the repair.

No to the 5200 question .. yes to filling it with poly/cabosi/ chop strand putty ( as long as its not through the hull ). Then lamination of glass wrapping up on your transom.

YD.

I thought I was clear on this suggestion .

Thats why Im saying.. clean it up ready for glassing. Cant tell a whole lot right now when your looking at a repair thats not even been explored yet ..

The suggestion of HOW to repair that I made is for the outside " as long as its not though the hull ".

Regardless .. I would repair the outside this way no matter what. You may or may not need inside glassing depending on the repair.

Nobody knows if its through the hull until you get all the bad glass removed. Sometimes it looks like its not through .. but it will be once the grinding is done.

Hope this helps clear things up.

Get them pics up .

YD.

 

[Yacht Dr.]

Re: fiberglass repair

Maybe my eyes are fooling me but the hole appears to be in the hull, actually in the boats keel and I swear I can see through the hole...

I think what we are seeing is the transom shot out at the drain plug.

I think I see someone already tried to repair that area because it was blown and cracking.

I dont think the inner trans glass is shot .. its just the wood transom core thats shot in that location .. but who knows for sure without pics from the inside ( even then it might not show you Anything ).

Thats why I suggested grind into that thing and find out whats going on there.

It would take me 20 seconds to look at it Personally on hand to be able to tell .. but 2 fuzzy pics .. not gonna do it for me.

I would grab a grinder and die grinder and 5 mins I would tell you if its gonna be on inside or not.

Give him some time .

YD.