Clean away any wax with white spirit or thinner but make sure the fibreglass is perfectly clean and the ding is thoroughly dry.
Clean the ding, trimming broken fibreglass edges with a knife and sand the immediate area with heavy sand paper to ensure the resin will bond. Tape around the edges to prevent the resin running off.
If the ding is on the rail, run tape across the ding conforming to the rail curve, leaving a gap to pour in resin and make sure it is sealed to prevent resin escaping and forming dribbles.
Cut up some fibre glass to fit into the ding. This will help secure the brittle resin and seal the repair from water entering your surfboard.
Small chopped fragments will help fill the open ding. Square pieces of fibreglass placed over the top of the ding will help seal it and provide extra strength.
Mix up enough resin to fill the ding. Mixing resin is a tricky procedure - If you add too much hardener to the mix, you'll end up with about 30 secs to work with it so always follow the instructions.
In hot countries a bucket of water will cool your resin container down if it starts to heat up too much. When the resin is concentrated in a large, deep ding, it'll heat up a lot quicker than when spread over an area thinly.
Correct mixing levels depend on the nature and size of the ding. The air temperature can also impact the type of mix you prepare but not so much in Britain!
The colder the day, the more catalyst required. Generally mix between 2 - 6ml of hardener per 250 ml of resin. Use a proper measuring cup to measure hardener, don't guess.
Mix the two together thoroughly, making sure you are in a clean environment and away from dust. Step 4
Pour the resin into the ding making sure all the little corners are filled. Try to get all the bubbles out of the ding by mixing gently - wooden lolly sticks are good. Don't over fill the ding as you'll only ending up sanding the excess off.
Wet the pieces of fibre glass in the resin container and work the resin into the ding until the silvery strips of fibreglass vanish. Use the fibreglass to fill the ding, again working out all the bubbles.
Leave your completed job to harden. Wash your hands in soapy water. Once the resin has just passed the gel stage (approximately 15-20 minutes after completing the job), cut excess resin away and remove the tape. Leave overnight in a ventilated area, preferably outside as resin stinks!
The day after applying the resin, use sand paper or a sander and sand the ding so it is flush with the surfboard's normal surface, using increasingly fine grades of sand paper.
Polish the newly prepared area with a rag and cutting compound. If you're a perfectionist, you can use an extra layer of gloss over the top to produce a nicer finish.
Cut the gloss back with the fine grade 'wet and dry' sand paper and buff up. Add water or saliva to this type of paper for best results. Now sit back and admire your handy work.