Gotta Hole

[Biggestjig]

October 2019 I hit a concrete bridge abutment. Paid $3500 to have the boat repaired.
August 2021 the $3500 repair job was failing - Soft spot developed. They said sorry but no warranty.
August 2021 - I tried to repair it myself. Basically ground back the soft spot and appiled a bunch of layers of resin and fiberglass. It lasted almost a year.
July 2022, I hit a stump with a piece of rebar sticking out and damaged the area again. Unbeknowndst to me, my 2021 repair was also failing and I have put a hole in the exactly same spot. Ohio River is tough on boats.
Late July 2022, I repair it again. This time, I ground back a lot further. I dug out as much of the wet foam as possible. Put a fan on it for 24 hours in 100 degrees direct sun out so it dried decent. The rest of the foam is still wet..... once I felt the area was pretty dry, I stuff the cavity with bondo. A lot of bondo at that. It harden nice, I sanded it down, feathered it our as best as possible. The bondo was basically a "strucutral layer" between the fpam and the outter layer. I then applied a bunch of layers of resin and fiberglass. When I finally finished, it was hard and smooth. No soft spots. The last 4 layers of resin was colored black. It actually looked good.

May 2023, the entire fiberglass patch is gone. All that's left is the bondo and its chuncked out.

At this point, I just want the damn thing fixed without spending $20K. It doesn't have to be polished fix, I just want it structural sound, safe and water tight.

I have attached a bunch of photos of the damaged area. Hopefully, I can get some expert advice on my next attempt at repairing this area.

TYIA

[ericjp]

It doesn't look like your are making/sanding a large enough area for the patch to hold. I'm sure any moisture isn't helping either.

[bpicinc]

Is there any boat fiberglass repair shops in your area? Lake Fork Fiberglass can fix it and spray a Gator Hull on it or Toledo Bend Fiberglass can do the the same with Gorilla Hull.

[FrickerDude]

Try epoxy and fiberglass instead of resin. Epoxy will bond better than resin

[rojoguio]

West Systems Epoxy is the only Epoxy I use. I have written numerous times concerning the adhesion superiority of Epoxy adhesion to Polyester adhesion. 3000psi to 300psi. That being said West Systems offers free downloads of how to fix holes, the percent of grind, hole backing for structural reinforcement, etc. Bud you need to download the Epoxy Repair manual and study it as it will guide you on the path to a repair that will be stronger than the original glass. If you reduce the file size of the images to 15 inches either direction you can post them in this thread where we can see how to direct you. If you read over my posts on the Champion and Blazer it will also educate you on what to do for a professional repair. We are here to help. Good Reading.

[Biggestjig]

Guys, Thank you for all the advice. I took it to a fiberglass repair shop originally and thier $3500 repair failed after 9 months. The other guy in town wants $15K grand to bring it back to NEW Condition.

So, I am stuck with making the repair myself.

I used West System's 105 Epoxy Resin + 205 Hardener on the previous repairs. And I agree, the sanding are is supposed to be 1/12 PITCH. When I attacked this project after the $3500 failure, I could clearly see they were no where near a 1/12 so I opened it up alot more on my first attempt. And even more aggressive on my 2nd attempt. It appears the 2nd attempt is much better but the main hole failed, not the perimeter.

The hard part is it's right on a ridge of the hull so that make it a lot more difficult.

I had a body shop friend suggest Duraglass. It's formulated with short-strand fiberglass fibers, and provides ultimate strength and durability on fiberglass panels and is 100% waterproof.

Have you guys ever worked with Duraglass?

[billnorman1]

You're doing the right thing drying out the area and grinding back so you have fresh used glass. Are you sure you don't have a broken stringer allowing excess flex in the repair area?

I certainly am not a fiberglass repair expert, but I have pieced my boat back together after hitting a piling and bolt and shattering the hull, rubrail and top cap. It SEEMS to me there is too much stress and not enough strength in that area. If it was new it would have the same stress as the rest of the hull but the stress would transmit to the rest of the hull. Maybe even add a stringer. In the words of many men, that's a nasty gash. I think the hull is flexing and killing the patch. Perhaps the only way to do it successfully would be to attack the fissure from both sides Absolutely dry the innards, then grind and patch it inside, then grind and finish a second repair outside. If you drive a bass boat like most of us that area gets pounded at speed

[APS]

do not use duraglass or kittyhair unless you want to repair it again down the road.

[Biggestjig]

Bill, Right now the boat is not leaking so I don't think anythng is damaged other than the outer layer on the bottom. This boat has the 3/8" Bottom Hull, 1/2" Closed Cell Foam Layer, and another fiberglass layer so it's a 3 layer hull. On my last repair, I opened it big time and dug as much wet foam out as I could. I didn't see anything damaged on the interior layer. Hopefully the stringer is still strong and undamaged.

APS., Check on the duraglass...and I really don't think Bondo is right filler either becuase its brittle. But it certainly served it's purpose so far.

[Biggestjig]

If I could flip the boat over and fill the void with epoxy, that would be awesome. Unfortnately, this damage is directly under the drivers left. I am pretty aggressive and I am will to try about anything but flipping the boat over is more than I willing to do. That would be a monumental task.

So, with the boat hoisted in the air, I tried so hard to get the West Systems 105/205 Expoxy Resin to work but it would pull away and air pockets would develop. It was so frustrating.... That's when I ran to the O'Reilly and bought the Bondo. I was able to completely fill to void, sand smooth, and really get a nice surface for laying in the fibergalss. Looked good, felt good at the time. Onv

My 3rd repair area was prbably 18" x 10" after grinding back to what I thought was close to 1/12 pitch. If you look at the picture, most of my reapir is still intact. It's only the area directly over the bondo. I need something that performs like bond but I need it stronger and less brittle. Once, I can get the void filled and the surface back to good. I will layer more fiber glass and finish the surface just the same as I did before because the perimeter of the area looks good right now.

Question, I have watched a ton of videos and this last one talked about Woven Fiberglass Cloth vs Fiber Class Mat. I used the woven fiberglass cloth previously, may that's the wrong choice? Should I have used the mat instead?

May 2023 - Repair Failure #2.jpgMay 2023 - Repair Failure #2.jpg

[Biggestjig]

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[billnorman1]

Quite creative on making boat jacks. I think I'd stack up a couple of old tires on rims under the center of the hull just in case one slipped. I once fixed a Mckee craft that had sat in water with a dollar bill sized hole in the center of the hull for years. The foam was soaked. After failing on my initial attempts I dug all the foam I could reach out, vacuumed any water I could find and then shot expanding closed cell foam in the hole. That stopped the oozing, I repaired the glass and my bud and I used it for years without issue. According to legend, fiberglass can always be repaired.

Gravity is not your friend.

[APS]

I would dig out the bondo and replace it with thickened epoxy resin. Thicken with cabosil after mixing and tape up something like a piece of cardboard with wax paper on it while it cures. Use a dremel and grinder to clean out any air voids and redo till it's good enough to start laying glass. I'd use 1708 with epoxy resin, wet it out before laying it up. It holds well under a boat this way without falling. Grind it down when cured and lay a bigger area same way. I normally use poly resin on these type of repairs but in your case I'd recommend epoxy. Be sure to run a fan on it while curing because it can create alot of heat, especially when mixed hotter than it calls for.

[Biggestjig]

APS, Thank you so much. Cabosil sounds like the right stuff. If I would have used this on the first attempt, I believe I would have been done. Bill Norman is right, gravity kicked my ass on the first 2 attempts.

Can I still use West Systems Epoxy 105 + Hardener 205 + Cabosil? or do I need a different epoxy resin?

What about fiberglass mats vs woven fiberglass?