Surfboard conversion to freerace (race fin placement)

[SmallWaveSteve]

I've been planning on shaping a freerace board for a while, when
I stumbled across a 7S Superfish surfboard (5'9), which has quite a few similarities in shape and dimensions to what I was thinking.

I'm planning on adding 2 front straps and 1 rear, but fins is the big question.

I have 3 MFC Freestyle UL windsurf fins (2 @ 22cm and 1 @ 20cm) that I'm thinking of using, but really don't have a clue on what I should be doing for fin placement. The rough plan for fin layout is no toe-in, and install the fin boxes with ~5 deg of cant.

Any thoughts on using these fins? (Particularly the symmetrical foil and less conventional shape)
Any suggestions on fin placement? (for surfboards I use the McKee layout guide, but with huge fins on a board like this I seriously doubt that's an option)

I'll see what I can do about some pics tomorrow.
Cheers,
SWS

[SmallWaveSteve]

The one measurement I eyeballs instead of measuring: how much depth is required for a powerbox fin boxes.

Answer: more than this board is thick.

Oopsies; looks like it's back to the build from scratch plan

[KUS]

The one measurement I eyeballs instead of measuring: how much depth is required for a powerbox fin boxes.
Answer: more than this board is thick.
Oopsies; looks like it's back to the build from scratch plan

one of the two reasons the smaller boards have A boxes, the other being slight ability to adjust fin...powerboxes also weigh more, not desirable. Have you considered mini tuttles? pretty bomber and you can fit fins up to 16cm or so but no adjustment and I guess you already have powerbox fins?? If not, check the selection of the Black Projects multifin range
http://advancedsafety.shawwebspace.ca/p ... cessories/
http://www.blackprojectfins.com/product ... wave-quad/

[SmallWaveSteve]

I do have the fins and boxes already. This was a personal challenge for myself to see what can be built for less than 250. Talked to an mfc distributor and lucked out with new old stock fins and boxes for dirt cheap (less than 100 after shipping and duties for everything).

Now that I'm going to have to glass one of my freebie blanks, I'll have to break the 150 threshold (still notbad for a complete board though :p)

Depending on what the foam ends up being it may be glassed with poly, so weight of the fin boxes won't be a huge concern; I'm not expecting the highest performance board in the world out of this considering it'll cost less than a set of used race fins ;)

[skywalker]

Make sure you entry the race June 22nd with it. Entry form in special events section!