I’ve found this thread very helpful. I’ve been drawing out plane shapes and fin configurations, waffling on tail design and layout.
I am a round pin type of guy. My current 13 year old 6’8" HWS is a subtle double bump round pin with a FU box and FCS thruster sides, and I have made many fins for it. I want something with more volume and railline for the next 10 years into my mid 50’s . So quad plugs with a FU center are what is going in. My drawings are so far just not looking right though.
I’m thinking about making a 6-3 x 21 board based on the Dwart outline. I like the wider nose outline on my boards.
I had to google dwart, but that’s the general outline I have in mind. Kept drawing mine with a single wing and it just does not look right. My shorter boards always have had fuller noses. I weigh 220 Lbs dry and am a front foot surfer, and normal pointy noses just never worked right for me. I’ve got a bad longboard hangover going on now too and want something to stoke me onto a sub 7 foot board again, instead of grabbing a 9’+ traditional single fin and going to the local super Soft wave in which a tradidtional longboard is always my board of choice
I found a 12 inch fin box that might solve the problem: http://www.ebay.com.au/itm/12-inch-Surfboard-Fin-Box-White/181612101745?_trksid=p2047675.c100010.m2109&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122130056%26meid%3D12ef2453cd574cc6b3e344b101455708%26pid%3D100010%26rk%3D3%26rkt%3D14%26sd%3D171031001936
Once it arrives I will check if it works with the various fins I want to try in it. There might be problems with snap-in fins or other unexpected complications.
I have decided to put the rear quad fins where McKee recommends. I have so far not been able to find any clear instructions except for McKee’s. I hope I got all the calculations right (adjustments for tail width etc).
First photo shows a stainless steel braided cable going through the thruster fin end points and the rear quad fin end point I had previously selected.
Second photo shows the cable going through the McKee end point for the rear quad fins.
The convergence lines with the rear quad fins placed as per McKee instructions:
Convergence point is about 1430mm in front of the nose.
Looks like the angle between front fins and rear fin is split near enough 50:50 by the rear quad fin convergence lines.
Putting the extra boxes in the McKee spots leaves enough room on either side to install more boxes later, if I want to experiment with more extreme fin placements.
The next few photos show a 5’8’’ x 22’’ x 3’’ Franken-Zot which had quad fins installed before I bought it.
The front and rear fins do not have the same convergence point. Rear fin convergence point is about 1650mm in front of the nose, and the convergence point for the front fins is even further away.
Front fins are 275mm from tail and 181mm from stringer, with about 5deg cant.
Rear fins are 110mm from tail and 110mm from stringer, with about 3deg cant.
Tail is 477mm wide at 12’’ from tail.
The board is ready for installation of the FCS2 plugs, but the 12’’ fin box might be problematic.
The leash plug is in the way and the tail rocker is going to make sanding down of the box necessary.
I will probably get rid of the leash plug and install the 12’’ box so that it just breaches the top surface of the board at the rear end of the fin box. Then I’ll drill a hole through the fin box and feed string through it to be used instead of a leash plug.
What is the best way to remove the old FCS2 box and the leash plug? Could I remove the FCS2 box so it can be re-used?
I think I found a close to ideal solution for how to remove a FCS 2 box from a surfboard with minimal damage to the box and the board: A Dremel with flexishaft and diamond bit, a pick and a fin is all that is required. Initially I used a Dremel cutoff disk to go around the box once, then a conical diamond bit, then the cylindrical diamond bit in the photo. I think next time I’ll go straight for the cylindrical bit. I measured the depth of the box, added 1.5mm for wall thickness and arrived at 17mm for the required depth. After ‘routing’ to 17mm with the diuamond bit, I inserted the pick, pushed it under the resin layer and rotated it 180deg while moving it around the box. A vacuum cleaner was used for suction to suck out the debris as I was working around the box. The diamond bit does not tend to dig in or veer off like some Tungsten cutters tend to do.
The resulting hole is only a couple of mm larger than the box and a couple of mm of the stringer remain stuck to the box. I have no doubt that the box can be cleaned up and re-used.
This method beats trying to rout through the Titanium rod in the FCS2 box, I guess.
The 12’’ fin box has arrived and works very well with all the fins that I have in mind for experiments with this board.
Rather than building new extreme options, I think I will place the 12" box so as to allow fin placements including almost all ‘stock’ options.
When the 12" box is just far enough back to allow the rear thruster fin to sit where it would have been on an unchanged XF thruster Nugget, then the front of the box is only a few mm short of where a stock 10.5" box would be on a SF Nugget. The difference is less than the difference in srew-tab length of individual Gullwing fins, so the board will practically allow the entire range of Gullwing-fin placements, and much further back than usual, as well as the original thruster position.
By using an FCS longboard finbox adapter and an FCS fin, the rear thruster fin could even be placed a few mm further back than the original position. Best of both worlds and a little bit beyond!
The photo shows the 12’’ fin box in it’s intended position and a 10.5" fin box where it would usually be on a stock McCoy board. The Gullwing fin is placed in the ‘18.5cm from tail’ starting position recommended by Geoff McCoy.
