Template for racing swing keel design

[HillbillyWanderer]

Hoping to finally get back to working on my boat again. Have had other projects that have been taking my attention away from my boat. Looking forward to getting started again. I am looking to redo the keel and would like to get the best possible design for racing. Anyone able to point me in the right direction?

 

[CloudDiver]

C-22 Racing rules only allow for the original keel profile. A "racing" modification would disqualify you (or take a penalty). The best thing you can do legally is make a plywood template of the correct NACA profile and make sure your fairing filler is smoothed out to match.
A few members have done this... I didn't really think there was too much benefit for my keel and simply added my filler with a wide knife, then sanded with a home-made long board (long strip from a cut belt-sander belt on 1/8" MDF)... I just did it by eye really along what appeared to be the original keel shape. I am pretty happy with the results.

 

[pclarksurf]

Recent discussion of my template here: http://forums.sailboatowners.com/index.php?threads/today-it-gets-real.178757/page-2

And if you are somewhat tech savvy-- Design Foil (free trial download) allowed me to plot and print the various foil shapes and I transferred that to plywood and am using the same to build the profile in epoxy and fair accordingly.

 

[HillbillyWanderer]

May just order the CD kit. Yea, I'm not tech savy.

 

[pclarksurf]

Try this: (two options) I'm uploading a pic that is the NACA0015 foil shape formatted for a 16" chord length-- you could literally print this out and transfer to wood for a template. Option 2: use a browser and go here: http://www.airfoiltools.com/plotter/index

You can pick the NACA0015 template from the drop down-- insert your chord length in MM and print away..... Easy (ish). Save your money: @$tingy Sailor and @CloudDiver have a good perspective-- either don't fuss with it, or if you do-- at least get the Math right (CD Kit is close but no cigar).