Hull patchwork repair
- Thread starter AP0196
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You're not going to like this answer. Grind it out and do the job correctly. For one, it does not appear that the PO did much in the way of prepping the surface and cleaning it. That would adversely affect the epoxy's ability to bond with the hull.
Until all the patch is completely removed.
On the West System website there is a manual on how to do many repairs. It's free and can be downloaded. If you're new to working with epoxy and repairs, this is one of the best resources at a very good price.
www.westsystem.com
On the West System website there is a manual on how to do many repairs. It's free and can be downloaded. If you're new to working with epoxy and repairs, this is one of the best resources at a very good price.
Home | WEST SYSTEM Epoxy
The home of WEST SYSTEM marine-grade epoxy resins and hardeners for boat building, boat repair, home repair, and restoration.
www.westsystem.com
Also check out Boat Works Today on Youtube. Andy there shows how to do a bunch of different patches.
I wish I could offer a different second opinion, but I love a good night's sleep.
Indeed, I also recommend undoing and starting over. And like others mention, the proper technique isn't to patch a hole so much as rebuild the hull at that spot.
The good news is that doing this properly isn't that complicated or especially expensive. Patience, care, and giving each step a little forethought will give you a good night's sleep too.
Indeed, I also recommend undoing and starting over. And like others mention, the proper technique isn't to patch a hole so much as rebuild the hull at that spot.
The good news is that doing this properly isn't that complicated or especially expensive. Patience, care, and giving each step a little forethought will give you a good night's sleep too.
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You'll need to grind this. Angle grinder is the best tool but doing this in a confined space sucks. My advise is use as much tape and plastic as necessary to seal off the rest of the boat. Ground fiberglass gets EVERYWHERE. Use a good shop vac to capture what you can while grinding. It's best to use a vacuum with a HEPA filter and/or a long hose with the vacuum outside so it's not just recirculating it inside the boat. You'll want a full face mask as it has a double seal. Half masks only have one seal. Trust me, it makes a huge difference. It also protects your eyes much better. Safety glasses dont cut it
Well, you could do that, and then you would have new problems to figure out. And sooner or later you will dive into the wonderful world of fiberglass repair anyway. Might as well get your feet wet now.
Grinding out that small area won't be all that bad, but it will be messy, still the more protection you install, the smaller the mess afterwards.
If you use an angle grinder, use Flap Disks not grinding disks. They work faster than grinding disks. I've been using discs from Benchmark Abrasives, decent quality and a very good price.
Quality Industrial Abrasives and Tools | Benchmark Abrasives
Benchmark Abrasives carries a complete line of zirconia flap discs, as well as top-quality general-duty diamond blades and excellent surface conditioning
benchmarkabrasives.com
It really isn't a difficult repair. Folks are just trying to make it clear that you need to grind and rebuild - not patch, and that it can be a messy job if you don't do a bit of prep/setup. Honestly, if the boat is out of the water, the bulk of this is a weekend project, even for someone with no/limited fiberglass experience. The only time-consuming part of it is the finish work on the exterior - sanding and filling and sanding, etc. The less you care about perfection, the less time this takes, and that effort is mostly about aesthetics (once the area is basically smooth and sealed).
All told, this could be done in a week, dedicating only an hour or two a day. (I am terrible at time estimates, but something like that.)
All boat owners and yard managers underestimate the amount of time it takes to complete a job.
Since it was a thru hull, do you have access to the outside? How does it look out there? Really the best way to do something like this below the water line is to do it from both sides. And people are right -- it's not a hard or time consuming job really. Think of it like painting. It's mostly prep. The painting part goes pretty quick. I'm going to assume (I know, I know) that you're just going deal with the issue inside of the boat, and not do both sides.
You'll need to grind out what's there and back into solid material. I think the ratio is 12:1 or so. You'll have to go back a bit into solid material to get that kind of a taper. As people have said -- prep work will save you from having to wipe down all the surfaces (think about it like sanding drywall, it gets everywhere). A shop vac right next to the grinder / sander (or one with built-in dust collection -- I have a nice Bosch) will help a lot. This is the time consuming part. The rest is hurry up and wait.
Once you've got the area ground down, clean everything. Acetone works in a pinch, Total Boat surface prep is my go-to. Cut some fiberglass circles starting with a small one to cover the hole plus a little bit and increasing the size to the edge of the patch. Depending on what fiberglass thickness you use, you'll need a bunch of pieces. I did it on a Catalina 22 and only had 6oz cloth handy, so I used like 10 - 12 pieces. With something like 1708, you won't need that many (but probably more than you think).
Grab a sheet of plastic (lay a garbage bag flat) and apply some epoxy to the smallest patch then to the hull. Put the fiberglass patch over the hole and smooth it out with a disposable paint brush as best you can. Repeat with the remaining chunks of fiber glass.
Let the epoxy setup, and sand / fair if you want (again Total Boat 2-part epoxy fairing compound) sand again, repeat as needed until it's perfect. Or, until you decide it's good enough. Slap some paint on it and call it done.
The hardest part is the prep and grinding. The epoxy part is a 30 min job and then you wait for it to cure.
You'll need to grind out what's there and back into solid material. I think the ratio is 12:1 or so. You'll have to go back a bit into solid material to get that kind of a taper. As people have said -- prep work will save you from having to wipe down all the surfaces (think about it like sanding drywall, it gets everywhere). A shop vac right next to the grinder / sander (or one with built-in dust collection -- I have a nice Bosch) will help a lot. This is the time consuming part. The rest is hurry up and wait.
Once you've got the area ground down, clean everything. Acetone works in a pinch, Total Boat surface prep is my go-to. Cut some fiberglass circles starting with a small one to cover the hole plus a little bit and increasing the size to the edge of the patch. Depending on what fiberglass thickness you use, you'll need a bunch of pieces. I did it on a Catalina 22 and only had 6oz cloth handy, so I used like 10 - 12 pieces. With something like 1708, you won't need that many (but probably more than you think).
Grab a sheet of plastic (lay a garbage bag flat) and apply some epoxy to the smallest patch then to the hull. Put the fiberglass patch over the hole and smooth it out with a disposable paint brush as best you can. Repeat with the remaining chunks of fiber glass.
Let the epoxy setup, and sand / fair if you want (again Total Boat 2-part epoxy fairing compound) sand again, repeat as needed until it's perfect. Or, until you decide it's good enough. Slap some paint on it and call it done.
The hardest part is the prep and grinding. The epoxy part is a 30 min job and then you wait for it to cure.
Haha im not giving up on her yet. Just a steep learning curve.How much are you selling yours for?
From the outside it looks fine. It’s actually really hard to tell where it even is. So im afraid of i grind the entire patch out I’d potentially do more harm than good. Most of the patch looks solid it just is chipping in that one part.
Would the job be possible with a rotary buffer and sanding disc? Would wet sanding cut down on airborne debris or would that just create a mess I’d have to wipe up?Well, you could do that, and then you would have new problems to figure out. And sooner or later you will dive into the wonderful world of fiberglass repair anyway. Might as well get your feet wet now.
Grinding out that small area won't be all that bad, but it will be messy, still the more protection you install, the smaller the mess afterwards.
If you use an angle grinder, use Flap Disks not grinding disks. They work faster than grinding disks. I've been using discs from Benchmark Abrasives, decent quality and a very good price.
Quality Industrial Abrasives and Tools | Benchmark Abrasives
Benchmark Abrasives carries a complete line of zirconia flap discs, as well as top-quality general-duty diamond blades and excellent surface conditioning
If it's that poorly done on the inside, who knows what kind of work was done on the outside
I don’t think it was necessarily poorly done it’s just probably a 20+ year old patch and one corner didn’t bond quite as well. The end goal is to keep water out. I did I pretty thorough tap test on the outside and it sounds solid. I’d like to start with the least involved option first and work my way up as needed.