FCS Fusions Thruster to 5-fin conversion: Step by Step
I had a buddy ask me to convert his FireWire alternator after seeing the rear quad fins I dropped into my hypto krypto. We're going to Nica in a few months and he thought it would be worthwhile to have a quad when we go down.
Should be a good learning experience for me as I've never set in fusion boxes.--buddy is a dedicated FCS guy and had the jig, bit, etc. Plenty of pics to come....however, anyone on here regularly use fusions. Interested in some advice on installing if you have a vid, suggestions, etc. I assume it's a lot like futures install but placement of jig looks different , etc.
There's an older jig, and a newer one, and they're slightly different. Just make sure you set the jig down with the correct alignment. The rest is a piece of cake. The hardest part will be getting the fin layout right.
Keep in mind, though, that the Fusion system is a pre-glass system. That's not saying you can't do it... it's just gonna be harder to fair it all flush and smooth once you glass over the boxes with two layers of cloth, and a sanding coat. The easiest approach post-glass is the old plug system. They're designed to be installed after glassing (but before sanding).
Thanks for the tips/links LBC...I'll check out the video when I'm ready to route out. At this point just getting my fin set up prepared...dims., etc.
Setting up a stringer on these boards isn't too difficult, but just requires multiple measurement from the stringer. Although I would typically snap a line from the nose if I were shaping this bad boy...the numbers we're within 1/32...so I was happy.
From there the dims were fairly easy to set up...basically a modified McKee placement. I was too lazy to go out to my shed to get the placement numbers so here is a pic of them as well as the placement lines...
Also, for those of you wondering about the QC of some of the big name board manufacturers the pic below should be pretty informative. Fin set up was off by an 1/8" on the right side...not the first time I've ever seen this from a large name manufacturer...and certainly not the last.
When you're adding fins like you are, and you come across errors like that, the important thing to remember is that the new fins' placement should be accurate relative to the other fin on that same side, and the rail on that side. It matters much less whether the fins are symmetrical to the opposite side of the board (as you can see on the original layout). Just make sure that your fin placement is the same distance from the rail, and from the forward fin, on both sides. In other words, measure the distance from the leading edge of the new, rear fin, to the trailing edge of the forward fin, and make sure it's the same on the other side of the board. Then measure the distance from the trailing edge of the new, rear fin from the rail, and make sure it's the same on the other side of the board. The distance from "stringer" (center line, in your case) is less important than the distance from the rail, because you're really riding only one rail at a time, and you want it to respond the same way on both rails. Unless you want to do something asymmetrical intentionally...
I'd pay close attention to the alignment in relation to the nose of the board. I make my rear dot then I use a straight edge to a pre determined distance from the nose of the board to determine the toe in. I find this method to be more accurate than using the shapers square to measure off of the stringer. If it were me I'd take a straight edge and determine where the existing side fins intersect in front of the nose of the board then I would set the toe in for the two new fins to intersect that same point. Hope that helps.