I have several spots where there is a large spider crack in the gel coats, and I know on small ones to grind out the crack to a "V" and fill it with gel coat or bigger ones with fiberglass. But as you can see in the attached pics is an example of one on my boat and am looking for a manageable way to fix this. The large crack port of the cleat I know will need more I just using this pic as an example of the spider cracks. Also in the long run I would not like to repaint the whole deck right now so that things don't look patch work. So a I am asking the group as many of you have dealt with this and might have found a good way to address it. Thanks for your eyes and knowledge on this.
Spider Cracks in gel coat
- Thread starter Andiamo 34
- Start date
A great source for gelcoat repair info can be found at the "Boatworks Today"
YouTube channel.
Andy covers this subject and a myriad of similar topics in detail in his older videos.
Look for the "Videos" tab or the "Playlist" tab to locate the series on spider cracks.
YouTube channel.
Andy covers this subject and a myriad of similar topics in detail in his older videos.
Look for the "Videos" tab or the "Playlist" tab to locate the series on spider cracks.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,308
Regarding your cleat, I would inspect the backing being used. I suspect it is either fender washers or less. I would be certain to provide sound backing before I exposed the cleat to further damage.
Additionally, it looks like there may have been some collision damage to the deck in front of the cleat.
Andy would be a good resource to understand what and how to make the repair.
Additionally, it looks like there may have been some collision damage to the deck in front of the cleat.
Andy would be a good resource to understand what and how to make the repair.
I would recommend checking the core under the cleat. My guess is that the cleat bolts leaked and let water into the core. The core would soften and let the fiberglass in the area flex more, leading to the cracking. If that’s happened the gel coat will just crack again after the cracks are fixed. If the core is wet you’ll probably need to dig it out, replace with fresh core and lay new glass and gel coat or paint over the top.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,308
This is a sound strategy
An alternative, dig out and vacuum out all of the core you can access from the bolt holes. When the area is "DRY", plug up all holes you find in the area, start to fill the area with resin. A thin penetrating epoxy resin at first then a thickened epoxy resin near the bolts and under the cleat.
The goal is to build a solid epoxy core around the area of the cleat.
Then go about repairing the gelcoat.
It seems to me the area of craze lines is fairly broad. I'd say that could mean a broader area of softened core then could be treated through the cleat screw holes although that wouldn't be a bad place to assess the extent of softening - not the area of softening.
I could live with the cosmetics of the crazing.
The treatment could be done with a grid of holes, cleaned out and filled the epoxy/ filler. The grid would lend structural stability without opening the deck or underneath. With the grid the area of softening could be assessed. Maybe that would drive a decision about how extensive the repair needs to be.
I could live with the cosmetics of the crazing.
The treatment could be done with a grid of holes, cleaned out and filled the epoxy/ filler. The grid would lend structural stability without opening the deck or underneath. With the grid the area of softening could be assessed. Maybe that would drive a decision about how extensive the repair needs to be.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,308
The type of crazing leads to wanting to inspect the core.The cause, I’m guessing, was triggered by water intrusion at the cleat or at the damaged area in front of the cleat. Inspection would be needed. If the backing plates for the cleat are washers then I’d suspect they are deformed from the upward pressure tying off the cleat to outside forces. As the water weakened the core to deck bond I can conjecture that the deck was flexed and the spider cracks resulted from the deck core bond collapse.
Addressing this problem can be :
- Serious-rip up the deck, remove the core, attach new core, reattach the deck, repair to pristine the gelcoat
- Dry the area of deck and core. Use suction to remove water and moisture. Remove as much of rotted core as possible. When moisture has been removed douse with denatured alcohol. Drill some vent holes. From the cleat hole begin pumping in epoxy. The goal is to fill the voids with epoxy using the existing remaining core as a bonding agent
Boat age and willingness to spend the time and money are limiting factors.
All good ideas above about exploring the area and possible ways to repair the core. If the deck surface were intact I would definitely go to the drill/dry/fill method. In this case, given the existing damage to the skin, it might just be easier to pull the whole skin off to make the core repairs easier. Fixing the cracks would take a good amount of effort anyway, so rebuilding the skin might not be much harder.
Whatever repair plan is chosen this should be part of it. The bolt heads seem to be sitting proud of the cleat, which suggests it was a previous owner addition. My guess is the previous owner didn’t use any thickened epoxy to protect the core, and that’s the root cause here.
Whatever repair plan is chosen this should be part of it. The bolt heads seem to be sitting proud of the cleat, which suggests it was a previous owner addition. My guess is the previous owner didn’t use any thickened epoxy to protect the core, and that’s the root cause here.Thank you for help on this and the understanding, I own a boat so I will ALWAYS have something that needs to be fixed, just hoped someone had a magical spray....LOL
The cause, I’m guessing, was triggered by water intrusion at the cleat or at the damaged area in front of the cleat. Inspection would be needed. If the backing plates for the cleat are washers then I’d suspect they are deformed from the upward pressure tying off the cleat to outside forces. As the water weakened the core to deck bond I can conjecture that the deck was flexed and the spider cracks resulted from the deck core bond collapse.
Addressing this problem can be :
It is a solve the problem with minimal intervention. You can always cut open the deck. If you can fill the void and get some bond the deck should be stable and allow you to do the cosmetic work on the gelcoat.
- Serious-rip up the deck, remove the core, attach new core, reattach the deck, repair to pristine the gelcoat
- Dry the area of deck and core. Use suction to remove water and moisture. Remove as much of rotted core as possible. When moisture has been removed douse with denatured alcohol. Drill some vent holes. From the cleat hole begin pumping in epoxy. The goal is to fill the voids with epoxy using the existing remaining core as a bonding agent
Boat age and willingness to spend the time and money are limiting factors.
Thank you and yes P.O. did not do much to stop any issues, so I am tackling them one at a timeAll good ideas above about exploring the area and possible ways to repair the core. If the deck surface were intact I would definitely go to the drill/dry/fill method. In this case, given the existing damage to the skin, it might just be easier to pull the whole skin off to make the core repairs easier. Fixing the cracks would take a good amount of effort anyway, so rebuilding the skin might not be much harder.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,308
By plug up I mean to put gorilla tape on them. Have an open hole at the high point and a second hole a bit lower. You fill the upper til it reaches the lower. Let to harden then repeat. That way the air escapes and the void fills with epoxy. Second shot you can use thickened epoxy to a creamy state. I use cabosil as the thickening agent.