I have been having trouble with the new FCS fusion plugs in a quad kneeboard I have been riding. I have broken 1 out twice and just found that the 2 right side plugs are damaged.
These are crushed in on the back, behind the trailing edge of the fin. Has anyone else had problems with these plugs ? I know I take alot of poundings but it still seems like a 4 plugs in year is a little excessive. Am I just screwing it up or are they installed badly? or just weaker plugs?
Thanks for any help
Jim N
Pics would help diagnose this.
From my experience using the pillar-style plugs: Usually that crushing behind the plugs happens when you strike something with the fin, the front grub screw loses its grip, the fin rocks backwards, and the trailing edge digs in.
My only experiece with fusions has been in my Coils, and the install is rock solid. The plugs have also impressed me; I did a really dumb thing that inadvertently tested the strength of the plug material (text copied and pasted from my review of the fusion plugs that was posted at www.eastcoastsurfer.com ):
I stupidly left the key in one of the plugs when I removed the old wax off the board today while it was lying on my 
living
room floor. Because the board was sliding all over the place, my knee,
and my 180 lbs, was on the traction pad the whole time. The key got
bent to hell (see pic), but the plugs are 100% fine (whew!). Kinda
blows my mind that the thin part of the box near the grub screws did
not crack under all that leverage and grinding, so I feel this is a
testament to both the strength of the install as well as the strength
of the material of which the plugs are made.
Thanks Hakeysaky. I will try to get a couple pics loaded - I didn't mention but this is a poly board
I agree, It looks to me like I hit the front of the fins, they pivoted and crushed the back. Just wondering about others experiences also.
I ride this in hollow OBX beachbreaks, lots of pulling in and getting worked
Guess I need a Coil KB LOL
Thanks
Jim N
Made 6-7 boards from really crappy to ok over the past 2 yrs. Have only used fusion plugs and have had everyone and anyone use any of the boards from kids learning to pretty acomplished guys and though they have have been abused I have never had a problem with the fusion plugs. First two boards I did as they say on the website with placement and then a patch and then laminate. Rest I have done after laminating, routing the outline, set the plugs then hot coat.
Hackysack,
I wasn't aware that it was possible to bend such a short key. You must have really been using all 180lbs. It is impressive that neither the plug or install didn't fail.
FCS Fusion is far superior to their round plugs. Fusion was originally designed for installing into EPS foam and FCS spent considerable time before deciding to use a flange based system to distribute stress loads versus the round plug skin to skin connection.
Through the 1980's I researched and developed many approaches toward fortifying fin boxes that were orignally designed for surfboards then being installed into high performance sailboards. The amount of torque being transmitted from sails and mast down to the fin were blowing fin boxes out right and left. As we became better surf sailors, we were destroying boxes while getting 30, 40, and 50 feet of air off waves at places like Jalama, Hookipa, San Francisco Bay, and the Columbia River Gorge.
In another thread I go into great detail as to the many techniques we tried and eventually developed in finding a solution to this problem and what the inherent problems fin boxes had in those days.
Ironically, the skin to skin connection, coupled with the advent of a one part box (Chinook vs. Fins Unltd aka Bahne box) proved to be the superior approach and ultimate soluion.
Back to the case in point: FCS X2 plugs versus the FCS Fusion. While the X2 achieves a skin to skin connecion, that connection is substandard for a number of reasons. First the ring of reinforcement surrounding the plugs is not substantial enough to resist eventual cracking: either thru the deck glass particular when the leading edg eof the fin is hit, or when a fin experiences harsh lateral force thereby cracking a corner of the receiving slot that accepts the fin tabs. Look at the tab entry for the slots and just see how little material there is between the corners and the outside wall of the plugs. The installation of the X2 plugs is also time consuming, and labor intensive with an inherent risk of overheating the plugs due to exomthermic buildup. I repair a lot of them.
Now look at a Fusion cassette. They are light, one piece and easy to install in a quick and efficacious manner. No worries about setting these in with too hot a batch for most craftsmen. They have introduced high density foam around the base of the cassette underneath the flange and a slatted design allows some dispersion of stress through flex. 'Keys' weredesigned in the X2 FCS plugs for resin to interlock, with the plug, further strengthening the installation and to prevent turning. The cassette simply doesn't have this problem due to its design. The Fusion is prepped to accept paint if one chooses to incorporate that aspect into the installation, and the design is easily installed and fiberglassed over.
As far as your problem, I think it is largely as you surmise: you yourself stated you see evidence of hitting the leading of of the fin(s). This would result in the damage that you describe. And the force had to be considerable with a proper installation of the Fusion system. If you look at the physical nature of a surfboard fin, even a glassed on fin could be straight armed from a side position and snapped off. But if you were to try that straight on into the leading (or trailing edge for that matter) you would not displace the fin at all and only come away with damage to your hand. It doesn't take a rocket scientist to know that breaking a fin that is about 1/4" thick is a lot easier than trying to rip out one that is 4-1/2" long.
Both Fusion and the FCS plugs were designed with the idea that side force would break the tabs so you could simply replace the fin without having to repair the insert. Guess what? It hasn't worked out that way with the round plugs. What should have been the ultimate fin plug (FCS X2) didn't turn out quite up to snuff. Sure they take a lot, but from an engineering stand point they are substandard. The flange ends up working out better in actual apllication. I had one customer that rides a retro fish with RTM (Resin Transfer Molded) keel glass fins snap one off riding too close into shore. He told me "the Fusion sustained no damage. I went and bought another fin and went back out".
I will never put FCS round plugs in any board I do ever again. I'm absolutely blown away by still seeing the largest surfboard companies in the world sticking round plugs in their boards. Maybe they WANT themto break and have the board disintergrate sooner than later?
Your ultimate solution would be to have a system that allow the fin to release if hit hard from straight on, leading edge impact. If you do not want to change systems, try taking a fine hack saw blade or file and creating an intentional shear point line on the leading edge of each of your tabs on your front side fins. You will need to experiement a bit with this, but start by sawing the line right below the actual fin (picture the line being cut above the grub screw) and try say, 30% of the tabs being cut. I think you will still have substantial enough strength for side pressure w/o the tab breaking. Or maybe even g closer to 50% of the tab. Then when you hit your leading edges of your fins in those hefty barrels you love, the fins may just snap w/o any damage to your Fusions. If you don't want to do this. Just stick the leading edge fin in snugly with some scotchtape for a snug but not screwed in fit.
Then go surfing.
I agree 100% with Deadshaper. All my boards have been equipped with FCS Fusion boxes for the past year and I didn’t experience any return. Granted, my production isn’t very important but I do feel that the system is quite strong and easy to install as well. I feel free to say this as I always turned down the previous FCS plugs as being unreliable, even when correctly installed.
…don t work for shapes with channels, like bonzers…
Even the 9 degree box? Their “bonzer” fins have a built in cant, seems like you could make that work. On a channel bottom, it seems like it could be a problem, but it seems like it would be a problem for other fin systems as well. I wonder if you couldn’t modify the side of the flange that’s on the channel edge to make them work. That’s why I like the original plugs on channel bottoms, because of their small footprint.
Personally, I’ve never experienced any plug failures unless it was caused by the rider impacting something, usually a pretty hard hit to cause them to break. I’ve jumped off rocks and bumped them, been dragged over reef, feeling the fins hitting bottom and they’ve remained intact. May be a function of proper install as much as plug integrity. I think that’s the plug design’s weakest link is that the system is only as good as the install. I have to qualify this statement with the fact that I’ve only done 150 boards or so with the FCS plugs, so that should be factored into my “success” story.
That said, I only use the Fusions anymore when using FCS systems. To me, it’s a much easier installation process than the plugs.
The FCS fin keys were intentionally made with softer metal than the usual tempered Allen wrenches aka hex keys. This is to allow them to strip out before the grub screws.
sorry, sent this twice… so here is an edit. Reverb: why bother using a system on the Bonzer triangular runner fins? Why not just glass 'em in and leave them? How often do Bonzer guys change their runners?
Hey Jim,
What was the glass schd? 1x 4oz with patches?
Just curious as want to put fusion on my latest as they sound pretty solid......
Cheers
Moonfish - not sure?, board is built pretty solid may even be 6 oz bottom
Thanks Deadshaper and everyone else who responded for the input. I figured it was probably me and not the plugs everyones experience seems to back that up.
I looked at the board again, I can see where the trailing edge point of the fins impacted the glass and pushed in the glass and started the failure -
Thanks for the help and the ideas for preventing it in the future
Jim N
If it's a 6 oz bottom the glasser may have thought he could get away without the patches. A flange system is only as good as the install. If the cassetes were a little high and the fiber gets sanded off, that could doom it also. And of course you could have just hit the bottom really hard, even a good install with 2 x 4oz e-glass isn't going to survive that.
Comparing to our boards isn't fair, we've got way more fiber, and much tougher fiber, over the flange. Most of ours are hooked into the deckside also.
i prefer to route the boxes after lam and patch over them. so you are not chasing bubbles on a poly lam. but i guess with UV resin it would not be neccesary
Is there a way to change the cant of the plug after routing such as making a 9 degree into a 7 degree.
Route the hole a little deep (so you don't get a high side) and ''set'' the cassete to the angle you want before the lamination. You should have about 2 degrees of wiggle room. The 9 degree is intended to be used mainly on concave bottoms where you're going to lose a few degrees when the cassete sits flush in the bottom.
I know I read this before on here but how do you keep the bubbles out if you place the plugs prior to lamination. I tried cutting little squares out of the glass to fit the flanges that are there but the few boards I did like this all had bubbles. I eventually used alot of resin to make the plug flush to the foam and then laminated. A local shaper told me to just set the plugs after lamination so I changed.