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Sep
The process of fixing a hairline crack differs from that of a spider crack. You can sand by hand or with an electric sander.
The instructions direct you to clean the cracks out with a fine needle and then to wash rinse and dry.
How to fix spider cracks in gelcoat. BoatUS Magazines Mark Corke shows you how to easily repair those pesky spider cracks that show up in your boats fiberglass gelcoat. While this may seem lik. Hairline spider cracks must be opened wider and filled with an epoxy filler to be permanently repaired.
Learn how in this tutorial with Andrew Price. How to fix spider cracks in Gelcoat we will repair the spider cracks and make an attempt at color matching. Building the Explorer Episode 29.
The more flexible the panel or surface the more likely the gelcoat will crack. Thermal Fatigue Crack Thermal fatigue cracks result from constant expansion and contraction of the gelcoat film. Cracks are identified by short discontinuous sections and are usually grouped in sections.
This can be done by using a Dremel. Once the crack is open and it has a good size you can sand and clean the area. For cleaning you may use acetone or soap and water.
Now you are ready to use the Gelcoat Putty. Mix in a 1-12 ratio of MEK-P Catalyst into the putty and mix it properly. Use a putty knife to fill in the spider cracks.
The instructions direct you to clean the cracks out with a fine needle and then to wash rinse and dry. Although slightly tedious the needle step is very important. Do not attempt to widen the crack-the Fix will seep into very thin cracks.
They then direct you to carefully fill level and wipe around the crack. And let the Dremel do the workseveral shallow passes will produce a cleaner more accurate job than going for a single deep forced march. Note that I have started to route out the hairlinespider cracks emanating from the hole.
To repair these cracks and have the repair last IMHO you need to route out the gelcoat down to the glass and provide enough surface area for the new gelcoat to adhere. If you dont get down to the bottom of the crack the crack will telegraph and. The process of fixing a hairline crack differs from that of a spider crack.
Heres how to fix a Gelcoat hairline crack. First drill two holes on the ends of the crack to prevent its front from extending further during the repairing process. Step 1 Clean the area with acetone and a rag to remove any dirt or other impurities.
Step 2 Sand the damaged area with 100-grit sandpaper to roughen the surface. You can sand by hand or with an electric sander. Step 3 Wash the area with acetone a.
The only way to know the cause of the stress crack is to grind along the stress crack with a dremel type tool until you hit fiberglass. Grind the cracks out and pay attention to gelcoat thickness and the general binding of the gelcoat to the. The instructions direct you to clean the cracks out with a fine needle and then to wash rinse and dry.
Although slightly tedious the needle step. Spider cracks in the floor will not generally lead to water intrusion unless a pressure washer is applied directly to them. I see your options as this.
Leave as is and enjoy boat regardless of minor spider cracks. Repair cracks by your self for under 50. Pay someone else to do it for you for over 500.
How do you get cracks out of gelcoat. A miniature grinding tool like a Dremel is ideal but the sharp point of a can opener will work too. If you dont open the crack you wont be able to force the gelcoat into the repair area or expose enough surface area for the repair to adhere Then sand lightly with 220-grit sandpaper.
Repairing Minor Gelcoat Cracks Use a rotary tool or scraping tool to open the crack into a V shape. You will need to go through the gelcoat to the fiberglass and open the full length of the crack. Next use 80-grit sandpaper to scuff up the opening you created.
Fold the sandpaper so you can get a corner of it into the opened crack. Remove sanding dust. Once finished remove all the dust from the sanding with the rag and acetone once more.
Tape off and apply gel coat. After masking off the area with painters tape use a paint brush to apply gel coat. Use a marine grade fiberglass resin and be sure to keep it in a separate container until its ready to apply.
Spider Cracks in Fiberglass Gel Coat. Near the end of last season the exterior bathroom door on my new 2013 Cruiser Viewfinder Signature 28BHSS developed a series of radial cracks in the fiberglass gel coat. The pattern fits within a 2 diameter circle.
I brought it to the dealer but they informed me that Cruiser denied the claim and would not. Then how do you fix cracks in gelcoat. A miniature grinding tool like a Dremel is ideal but the sharp point of a can opener will work too.
If you dont open the crack you wont be able to force the gelcoat into the repair area or expose enough surface area for the repair to adhere Then sand lightly with 220-grit sandpaper. Repairing spider cracks in gel coat. I have worked on many boats with spider cracks the best method i have used is a dremel tool to gouge the cracks and fill them with a gelcoat paste made with gelcoat and glass bubbles works wonders as for sand paper- you will have to change grits as you sand and fill.
What causes spider cracks in fiberglass. Spider cracks can indicate impact damage or serious structural problems that will need to be addressed to prevent spreading but most often they result from relatively inflexible gelcoat that is too thick. Stress by thermal expansion or when bulkheads and liners were installed can cause minor flexing.