Up til now I have either used set fins (glass ons) or fin boxes (single fin board) on my balsa boards and am happy with the results to date. Inevitably I will have to opt for one fin system or another either because people are constantly asking why I don’t use them or because I want to travel with my boards and am worried about airlines smashing my fins off!
Anyhow many of you have loads of experience with varying systems and i would like to know the pros and cons of the main ones ie fcs, futures, redx, locbox etc, ease of installation, durability etc particularly when applied to epoxy,eps, balsa boards.
I know that Bert does not particularly like using them because of problems of lack of flex etc, but If I have to use one or the other I would really like to know if there is a concencus as the various installation kits are fairly pricey and I only want to have to buy one!!
Fin selection is not too important as I can make my own.
I would at this moment opt for fcs because they are the most popular, I know that doesn’t make them the best, but the kits are available in the UK.
Howzit markyv, The balsa wood will make for a stronger base than foam so you are already ahead of the game. I have done FCS repairs on epoxy kiteboards and had no problems with the installation and the customer has had no plug failure in over a year and a half. Also you might not have to connect the h pattern to the deck since the balsa wood is stronger but I'd check on that first. aloha,Kokua
this one really needs to be disscussed in depth i think
i was looking at systems where you pool resin aroun the box but am slightly concerned of to much heat etc.
im gunna try speedfins hexalites as they are foam core and the system is strong and can be glassed over…(only draw back is it would be hard to mold basses for them)
mark
ive put in balsa inserts to spread the load and will probs glue in a balsa base after ive routed and before i pool resin.
i thought about fcs for travel board,but ill prolly just take a couple of sets of fins with me when i go traveling.
i would think it would be prefferable to be able to glass over a system cause you can maintain a water tite seal even if the base dislodges from the foam
The boxes that Bert made for himself look like they resemble futures and O’fishls. I would explore those first. Both glassed over and both do not connect the deck.
I think the windsurfers used to replace the 1 pound eps (directly under where the fin boxes are to be placed) with a higher density foam to add stability.
Sabs
I am a little unclear as to where you would use the balsa ply to add stability. Is it placed under the top flange of the box (future ofishl) or do you just add another layer of balsa in your sandwich in the bottom tail area.
Sorry this isn’t an answer to your post, but while were on the topic of fin boxes I’m still having issues of the glass capping lifting off the top of the box. I use chinook boxes with the post on them going thru to the deck and I replace the eps with a block of balsa 100mm wide by 350mm going from deck thru to bottom, I file off a 45 degree angle of the glass on the inside of the box to prevent the fin rubbing on and lifting the glass. The other day when someone else borrowed my board, when screwing the fin bolt in the screw driver rubbed against the capping glass and lifted a tiny area of the box. I know from past experience that this will now start to spread and water will start to track it’s way past the balsa and into the EPS. Do you think capping adds much extra strength? Should I bother to cap? Any other suggestions or has any one else had similar issues?
I always cap my boxes, chinook and fins unlimited, I don’t think much strength is added, it serves to stop water entering the core (whatever type it is), if any cracking should occur.
I am glad you have had positive experience, I was hoping to not have to tie to deck, the only drawback with fcs I can foresee is capping the inserts with glass, it isn’t done on pu/pe but I do like to follow Bert’s advice here and cap everything. Anyone tried it with fcs? Would probably set them in a 10mm or so thick layer of corecell under the balsa in the fin area.
Only thinking of thrusta fins, anything for single fin I would use a fin box, don’t like to fix through the deck so tuttle/power box out of the question unless I decide to build another windsurf board (way too much hassle!!)
Mark thanks for the reply, when the capping glass starts to lift on mine it gradually spreads out past the box then past the resin holding the box the gets to the balsa skin and from there the water goes into the balsa. Of course with my own personal boards I fix it before it spreads. But some customers haven’t been that observant.
I don’t think the base on snowboards are toothed. The plastic is prepared for a good bond, but I’m sure that the 5 bar + pressure used in a snowboard press helps too.
Unless you are 100% sure about the fins being perfect for the board I’d go for removable fins. Sometimes by just changing fins or even moving them ever so slightly changes the way the board handles so much in my experience.
Hi, friend. We have made kiteboards in heirex and epoxy and surfboards in eps and epoxy. We have already used whatever fin system that cames to our hands and actually we don’t have any trouble. The same concept we adopt for both boards:
you need to make the hollow or well or channel to the boxes, with a minimum recquiered of resin to glow or fix the piece (resin in high quantity allow increase of temperature at the final fase of its pot life and it is not a guarantee that is well fixed, ok with a bit more at the bottom of boxes to avoid that a screw hits the core).
this hollow or well or channel have to connect with points in the deck lamination or at a base well conected with it. this link with the deck is the guarantee that this insert is fixed.
the resin used with at least of 20% of milled fiber.
the inserts (fin box, cups, etc) have to be very well scratched and degreased.
all the hollows hydraulic fool of resin, no bubbles.
the place where you will put inserts with one more layer of weave cloth at least
Obs.: Soft cores with low resistance to compression are not confident to fix the box, many times we repared boards that didn’t crash against something and break just with the bottom turn, so you have to search where to fix it and the deck lamination is the place.
Our customers (friends) prefer the FCS style box because most places in the world are easy to get similary fins.
here is what i came up with for reinforcing my futures fins in my balsa sandwich boards…
check photos before reading…
got the idea from one of Bert’s post’s and photos (go figure?)… of course not sure exactly how he does it but this seems to meet the requirements of not linking the bottom to the deck and providing mucho more strength for impact etc… i am thinking about doing it under my glassons as well…
the foam is 5lb. 1/4" thick… i put a layer of 2oz under it and a extra 2oz layer over it… i do it all while pressing on the bottom skin…you have to really plan ahead so when you go to router in the boxes you hit the high density foam dead on… i basically lay out the fins copy all the measurements down, snap a few digital photos and go… pretty straight forward…
i have had tons of fcs boards since they came out and never had one problem… i think if you did a similar thing with high density foam. a circle, say twice the diamator of the fcs plug and say 1/8" or 1/4" deeper then the plug then you wouldn’t need to do the H to the deck, the plug would be set into the high density foam, the foam attached to the bottom skin, seems pretty solid…
that sounds good to me. the idea of the “H” in the FCS system is to keep the plug from “wiggling” loose in the hole. I believe Nev was the first one to come out with a fin system and it failed becasue after a whlie the fins would all wiggle, the same thing happend on an old Dymanic Balance twinzer i had in highschool. the Twinzer fins were not “glassed on” they were routered into the foam and they wiggled and leaked faster then you could believe… so as long as you have the plugs set in a way that they are not relying on the foam for support you sould be ok. futures and other “box” systems rely on surface area, and single fin boxes work because of the stringer, on windsurfboards single fin boxes are tied to the deck…
