oops I did it again! fiberglass hull repair thread

kingblazer84

Well-Known Member
Well since im an gigantic idiot and last night while screwing down a battery tray in my boat I put the screw right through the hull... fml. Looking for some options of repair guys, its about a 1/8" stainless wood screw that punctured through the hull, its in a voided fiber glassed box in my transom area. ( I did not notice the leak right away till launching)

It has had water get in there but just briefly as I went for a test drive this am and it started to bubble and fill the bilge with a little water at a constant rate at the dock. I stopped and re pulled the boat and dragged it home, pulled both hull plugs very little came out of the stringer hull plug maybe 1/16 of a cup and the bilge just drained like it should.

Now how do I attack this? cut the top of that fiberglass box out and attack from the inside or drill and fiberglass a plug in place on the bottom side. My assumption would be to cut the top off it and let air completely dry out the are and since its 39-42c here in kelowna. I figured Ill attack it during the long weekend since I have 4 days off.
 
drill out from underneath, tap in a dowel and recess it in 1/4". dowel should be just long enough so you have a min 1/4" to fill top and bottom. you can even put some resin on the dowel before you tap it in.glass it in both sides.
 
That's annoying. Grind it out 2-3 " around the hole top and bottom. Glass it back up on both sides. Grind and sand smooth. Very annoying for sure.
 
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I would not do it from the top side, like Trophywife and Mikep suggested would be best, it’s a small easy job, make sure it’s clean and dry
 
To get you through the season you could sika flex a bronze machine screw in there. Like a #10 and put the nut on the inside of the hull. It won't leak or corrode if you use the boat in the salt. Do a proper repair after the boating season. Could go as far as tapping the fiberglass to the correct size for the bolt. Could also sue a flat head bronze bolt. Not going to leak that way for sure.
 
To get you through the season you could sika flex a bronze machine screw in there. Like a #10 and put the nut on the inside of the hull. It won't leak or corrode if you use the boat in the salt. Do a proper repair after the boating season. Could go as far as tapping the fiberglass to the correct size for the bolt. Could also sue a flat head bronze bolt. Not going to leak that way for sure.
Well I’m gonna attack this bad boy next weekend, I think I’m going to the route of drilling out the hole larger then putting in a dowel plug and glassing over it in and out but I like that bolt idea! Here’s a pic of the hole
 

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Well I’m gonna attack this bad boy next weekend, I think I’m going to the route of drilling out the hole larger then putting in a dowel plug and glassing over it in and out but I like that bolt idea! Here’s a pic of the hole
Drill it out for a piece of dowel. Countersink the hole on both sided if you can. Epoxy or resin in the dowel leaving 1/4" on both sides of your countersunk hole for gelcoat. Mix your gelcoat and thicken it up with some talc. Fill your countersunk holes with gelcoat paste, let harden. Sand and repeat if it isn't flush. After it is filled flush sand out to 1500 grit, compound then polish and finish off with a couple coats of wax. The hardest part is matching the gelcoat color.
 
never been a fan of the dowel technique. below the water line, when it absorbs water (which it will) it will expand and crack the gelcoat cap. The only long term repair to the bottom of a boat should be grind both sides to a distance of 12x the laminate thickness away from the hole.
if the laminate is 1/2" Thich grind a 1/4" out of it both side and back fill with circles of 1708 glass stepping up in patch size for each layer until it is flush with the hull. grind/sand any high spots off the bottom, fair with some duraglass then roll some new gel over. It should only take a couple hours to complete all this. This way you know it is bomb proof, we aren't talking about transom repair here this is on the running surface, lots of pressure and stresses. like I said its a deal with it in the off season kind of thing though, run a bronze bolt in with some 4200 and have fun for now....
 
Well since im an gigantic idiot and last night while screwing down a battery tray in my boat I put the screw right through the hull... fml. Looking for some options of repair guys, its about a 1/8" stainless wood screw that punctured through the hull, its in a voided fiber glassed box in my transom area. ( I did not notice the leak right away till launching)

It has had water get in there but just briefly as I went for a test drive this am and it started to bubble and fill the bilge with a little water at a constant rate at the dock. I stopped and re pulled the boat and dragged it home, pulled both hull plugs very little came out of the stringer hull plug maybe 1/16 of a cup and the bilge just drained like it should.

Now how do I attack this? cut the top of that fiberglass box out and attack from the inside or drill and fiberglass a plug in place on the bottom side. My assumption would be to cut the top off it and let air completely dry out the are and since its 39-42c here in kelowna. I figured Ill attack it during the long weekend since I have 4 days off.

How about this?
 
So the hole is officially drilled to 5/8 and still quite wet what’s the best route to get that section to dry out? Heat gun held on the hole for a while or?
 
So the hole is officially drilled to 5/8 and still quite wet what’s the best route to get that section to dry out? Heat gun held on the hole for a while or?
Small space heater and time, don’t rush it make sure it’s completely dry, I have add issues with moisture doing FG repairs, I am no expert but my best results have been when it’s dry as a chip lol
 
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