This is the first time I’ve dealt with a problem like this on a surfboard. One of my friends bought an SUP from one of my other friends, and the board was in good condition. However, my friend who bought it wanted to use a different fin in this board. There was the problem. The Philips head screw bolt that held the fin in was just corroded and stripped to the point there was no purchase for a screwdriver to turn it to release in from the nut holding it in the track in the fin box, and the fin was just stuck.
For this, I used my trusty Dremel tool.
Of course, any rotary tool like that will work. I used a grinding wheel of fiberglass for this job. You can also use a diamond grinding wheel since they have such a thin edge and are good for detailed work (on left!)
To prevent harming the edge of the fin, I made the cut at an angle away from the edge of the fin, and while not moving the the wheel from the groove, I motioned the wheel front and back to open the groove a bit for a flathead screwdriver to fit into.
I stopped from time to time to check the depth of my cut to make sure I wasn’t cutting too far and reaching too close to the top of the fiberglass of the fin.
Once the groove was completed, fresh metal was clearly visible, and it was ready to be used as a groove for my flathead screwdriver. With steady downward pressure, the screw came out easily!
You can see the groove made by the grinder, and the corrosion as well.
Before installing the new fin, I took an extra precaution by applying two coats of a heavy duty wear clear nail polish on the head of the new screw.
There are really clever inventions out there like the Wonderbolt (I don’t get any thing from them, just thought it was neat), that are smart replacements for future situations like this. Might be worth it for the SUP’s, since around here, we take them in the river and ocean, so they might see some different types of corrosion.
On a different note, here’s a recipe I found for an “Ultimate Screwdriver” in case something doesn’t work out above: