When did you last check the cant of your bulb
- 13 hours ago
- 2 min read
Before I started this article, I though I better look up the definition of the world cant.
Here is what I found:
hypocritical and sanctimonious talk, typically of a moral, religious, or political nature. (Not helpful)
denoting a phrase or catchword temporarily current or in fashion. (also not helpful)
have or cause to have a slanting or oblique position; tilt. (Bingo, that helps)
I got a bit worried when I saw the first two definitions and thought I had been using the wrong word all the time, but the third definition allayed my fears
Bulb cant is the angle your bulb is to the waterline of the boat. There are various ways you can measure the angle of the bulb. I use a large sheet of paper and using a right angled triangle to make sure my alignment of the hull extremities are accurate I, line up the bow and stern on the top side of the sheet. At the same time I elevate the fin off the ground so it is parallel to the floor. Both need to be done accurately. Remember when the boat is stationary in the water, the 1st 20mm or so of the bow will be out of the water. The stern is usually just kissing the waterline.
Once the boat is aligned with the waterline, you can mark exactly the centre of the forward and aft extremety of the bulb and measure the angle to the bottom edge of your paper. The science says it should be approximately 2 degrees.
Why does this matter.
You know the impact of the tiniest bit of weed on the fin or rudder. Its massive and you can easily see the difference in performance of your boat from the shore. So imagine what happens when your bulb is at the wrong angle. It may not sound much but a degree or two off, could make a significant difference to the performance of your boat without you realising it, because the misalignment will cause drag.
If you need to adjust the cant, use a strond piece of plastic like a cable tie of old piece of thin fibreglass sheet and put into the slot before inserting the fin into the bulb. It maybe worth trying 0, 1 and 2 degrees to see what is fastest.
One thing is for sure, if your bulb cant is excessive and you can correct the angle, you will notice a significant increase in performance. Thats exactly what happened to me with my Marblehead. I went from an un-competitive to a competitive boat in the blink of an eye.
