Having the proper tools will make your life a lot easier. We can sharpen a turnfin in 20 minutes using this procedure.

Tools:

1. 7" Grinder (We have a Bosch)
2. 3M # 80515 Disc Pad Face Plate Ribbed, Hard Black
3. 50 Grit, 80 Grit adn 120 Grit Sanding Discs
4. Scotchbrite
5. Steel plate or structural angle
6. Clamps
7. Spray bottle with water

Process:

Clamp a steel angle or steel bar on the turnfin front tip to tip.

With the 7" grinder and a 50 grit disk, start to grind the fin in a horizontal back and forth motion. You want to sharpen the fin so that the leading edge is gradually feathered into the center of the fin.. The more you feather the edge, the better the fin will be.

The fin will start to discolor when the stainless gets hot. If the fin gets too hot, it will warp which will hurt the performance of the fin. When you see the fin discolor, spray water on it to cool it off. Do this every 15 or so seconds of grinding.

Once the leading edge starts to thin out, start on the bottom of the blade. The bottom of the blade needs to be sharp, but you don't have to feather much. This is a much faster process.

When you get close to having the entire fin sharp, switch to 80 grit, then to 120 grit. When you are happy with the edges, unclamp the fin and use the scotchbrite to clean up the burn marks. After you unclamp the fin, you will see a sharpening line. The more gradual this line is, but better the fin will be.

Place a straight edge on the inside of the fin to make sure you didn't put too much heat into it. The inside should be straight. If it isn't, the boat will not track straight.

Blazer Marine,  Cincinnati, OH (513) 598-1769

Email: Brian@BlazerMarine.com