Fiberglass Repair
by Glass Clown Boats

This is an old hole for a fuel fill. In the prep for paint, the owner asked us to make it disappear. This pictorial shows the process from start to finish.



1. Measure the thickness of the fiberglass. In this case, it's 1/8" thick.


2. Then multiply that number by 10. (1/8" x 10 = 10/8" or 1-1/4")
3. Now mark that distance around the perimeter of of the repair area.


4. Connecting the hash marks


5. A grinder with an 80 grit flap wheel will give me a nice smooth taper


6. As always, protect yourself (safety glasses too)


7. The repair area tapered back at a 10:1 ratio


8. Which makes the total repair 4-1/2" in diameter


9. Each layer of fiberglass should extend 1/4" beyond the previous layer


10. My fiberglass lay up schedule. Always alternate with layers of mat. Always finish with a layer of mat.


11. The fiberglass cut to a measured square.


12. Then round off the corners


13. Denatured alcohol is used...


14. ...to clean the repair area.


15. The repair must be supported from below to properly compress the layers of fiberglass.


16. A plastic spreader and a scrap piece of pipe does the trick nicely


17. The materials. Notice the extra rags and alcohol for clean up.


18. Resin is poured, then catalyzed with MEKP at 2% by volume


19. Mix the catalyzed resin thoroughly


20. Wet the surface area with resin.


21. Then wet out and add each layer to the repair. Compress the layers with a resin roller or by stipling with a brush.

22. Excess resin can be cleaned up with alcohol or acetone. Always wear gloves with acetone


23. Once the fiberglass has kicked, cover surface imperfections with fairing filler


24. Sand it flush and fair. Voila! No more hole.

Courtesy of Glass Clown Boats
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