Tri/Quad conversion of my old Goya, let the fun begin!

U2U2U2 · Posted: Thu Mar 05, 2015 1:06 pm Post subject:

The last 2 projects I did have trailing tri fin, current is a quad, w/slotbox rears and ProBox fronts.

the trailer is interesting, in that you can vary the size forward or rear to suit your particular taste.

the forward fins are inboard , but not so much as a twin. I like this set up.

I like K4s

manuel · Joined: 08 Oct 2007 Posts: 1158

Fins can be shaved to adjust for angle right?
More later, time to go on the water.

U2U2U2 · Posted: Thu Mar 05, 2015 1:17 pm Post subject:

U2U2U2 · Posted: Thu Mar 05, 2015 7:19 pm Post subject:

Exocet Original Wave, 105L , all slot boxes, fin position fairly straightforward, advise from MOO Custom UK. This worked exceptional, some drag, but very nice quad.

RRD Wave twin, additional boxes for quad, this was a great set up.

tried lots of fins, these are TFC with FCS fronts in ProBox

manuel · Joined: 08 Oct 2007 Posts: 1158

U2U2U2 · Posted: Fri Mar 06, 2015 10:54 am Post subject:

Quad or not, my impression of this board a is a tri fin, not QUAD, its not a wave board to start The addition of the quad/rear boxes would offer a twin and quad sailing option.
The additional weigh would not be great, but certainly more with 4 boxes.

You can certainly make a quad if you desire those traits over a 2+1 tri fin.

SURF Fins: True Ames make both Windsurf and Surf fins, the surf fins dont come in G10, AFAIK. For fins this size I have found no difficulty with strength, see see K4, which are a composite ..plastic is unkind but very hi tech plastic.

You can see toe in for some companies on the K4site. From the designer of Simmer boards, for symmetrical fin, 1.3--1.5 degree of toe

TWIST: The only windsurf fin that I know that have any are Witchcraft, they will come in only mini tuttle, the set of RTMs that I have from them I use all the time on my Chakra. I tries a set of surf ins that have extreme twist, straight line, horrible, turns great. My frien who is a NASA scientist did a pair of fiberglass ProBox for me, they are sym, and I really didnt notice much, asy may be better.

a drawing, there is no definitive placement of the cluster, the arrangements vary, but not by a lot, the individual company's have tested different positions and utilize what works BEST for that hull, hulls of course will be different.

U2U2U2 · Posted: Fri Mar 06, 2015 10:58 am Post subject:

this for surf boards has lots of good info, not written in stone

http://proboxhawaii.com/pages/technical/technical_primer.html

U2U2U2 · Posted: Sat Mar 07, 2015 11:28 am Post subject:

I have a lot of confidence in the ProBox strength, for fronts for a tri or quad really good. For larger fins , or the option to use them for quad rears I may use USBox, and probably reduce length some, much larger variety of twin fins that would work there. My larger ProBox fins are all hand made in G10.

TEST: The board is just a nose, the box was installed with just epoxy, no glass/carbon, the box was not sanded flush with the board, the fin.. a squareish piece of fiberglass had no slots for the fins to grip.

started with a hammer, difficult to swing from high to hit the 'fin' but had no effect, using the weight then and repeated hits did dislodge the entire box, I hit both side and fore aft. The board itself was a POS, but what I had to test with. I have removed the boxes after being installed correctly, and they are not easily removed, using a route with small cutter I went down the center of the box, the cut then allowed me to pry it out.

manuel · Joined: 08 Oct 2007 Posts: 1158