Interesting questions

Futures fin screw problem

Q: My wife's brand new surfboard has Future Fins and one of the screw holes has been stripped.  Am not sure how it happened.  The screw goes in ok for the first 3/4 of the way down, then at the end it just twirls and doesn't grab the fin.  The Future Fin company sent me bigger screws, but the same problem also happens.  Do you have any suggestions about what i can try?

A: most of the time, the problem is not with the screw threads, but with the fin base - when the base is too short, the fin ends up pushed against the back pin, which places the notch in the front "out of reach" for the screw. See if there is any kind of slop fore & aft. If there is, make little shims (out of yoghurt tub lids etc) and place those under the aft pin. Keep adding shims, until the fin just barely goes down in the front. Tighten screw. Presto - I hope!

Small area of flex

Q: I was hoping I could get a second opinion from you. I just discovered that my Exocet O-Wave 2 has a small area about ~6 inches left of the mast base box front end that flexes. The area of concern is about 1/2 the size of my heel. This area still feels firm but obviously stands out since there is no flex elsewhere. There are no visible cracks and no sounds when I press. Anyhow, the local advice and my inclination is to keep sailing until there are significant changes like cracks or soft mushy spots. Your thoughts and comments would be greatly appreciated.

A: sounds good to me! if this was further back, between mast box & straps, I would get nervous, since the stresses there can be remarkable. But if this soft spot is well away from the rail, and towards the forward end of the mast box, I would check it regularly, but keep going.

New Life for Old Longboards - Ducktails and Cutaways?

Q: It seems like the Kona and other new designs aren't that different from the older longboards, but they have added ducktails, etc. Has anyone tried adding a duck tail or cutaways to old longboards? Any thoughts on how well it might work? How would you do it?

A: like, with a saw Smile
no, really, the big difference between then and now is about 25 pounds, and those are a whole lot harder to shed than some bits in the tail.
But, hey, if ye olde sled gathers dust in the garage otherwise, why not go for it?
Eva

Cracked Powerbox

Q: I have a 1997 ON Race 289 (designed by Gunther Lorsch) that I bought used a few months ago. The board weighs in at spec. (6.8kg with pads and straps).
But I noticed that around the top of the power fin box screw access hole, there would be droplets of water "sweating" out.
Examining the interior of the fin box under a bright light, I can make out that the entire fin box has a hairline crack running from front to back the length of the fitting.
Since the board is still light, I have these questions:
1. Is the powerbox plastic casting encased in some kind of material that might prevent water from entering the core of the board? Maybe just migrating around the skin?
2. I weight 84 kg, and sail the board under a 7.2 rigged at minimum settings fully powered with a 41 or 44 cm fin. GPS has put me at 49 kmph. What is the likelyhood that the fin box will fail catastrophically under load? Should i specifically NOT jump it any more? ;)

I have been wondering if there is some sort of sealant that I could spray into the fin box that would seal that crack? Something that would not interfere with the seating of the fin?

A: good news is that most well-built boards have a substantial cartridge around their fin boxes that prevent water migration.
Bad news is that, yes, with a crack running around the entire fixture, you have lost its structural integrity.
Some sort of sealer squirted in there would, yes, seal the crack (but sealing would not appear to be a problem), but would do nothing to restore the strength of the box - which is.
its got to come out, I'm afraid!

Softop mast track

Q: I just managed to get an 11 foot softop.
Pretty slow for solo surfing, but I'm having fun tandem with the kids.
Want to drop a mastrack in it for summer schlogging.
It's EPS right, so can I use West system? Slow cure. Any better recc?
I wasn't going to re-inforce outside the box with divinycell or anything, not planning to load it up that much, and would prefer to keep the deck
gouge minimal.
Any input welcome, also position will be a guesstimate unless someone's done this.

A: you can reinforce it now - or you can reinforce it later... omitting that Divinycell really is a bad idea (there is a particular brand Epoxy sandwich board out there that thinks they can get away without the Divinycell (did anyone say "Boardworks"?) and one out of two I see here, leaks. Truly, it does not work!
As far as that gaping hole in the EPS: if you go at it slowly, patiently, with a sharp Xacto knife, you can remove a generously-sized bit of EVA foam, do your thing with the mast box, then re-install the EVA. I just did fin box surgery on a fully padded beginner board, and its not all that obvious, go see http://www.boardlady.com/customerpics.htm, its job #4712
 

Exposed Carbon

Q: I repaired my freestyle board that someone broke for me, so replaced the Divinicell (thanks Joel, I had a little left over from the last repair, still owe you a beer sometime!), glassed over, then finished with a layer of carbon weave over the top. Looks sick, but someone pointed out that leaving carbon exposed might not be too good as UV could damage it, or heat could damage to the EPS core. Should I worry? I live in the UK so it's not going to get massive amount of UV, but we occasionally get sunshine and wind together.

A: just go fast enough always, so the windchill keeps it cool! Or how about those nifty mister thingies they have at Disneyland?
no, honestly: the proof is in the pudding - uh, in the feel of the thing: if its uncomfortably hot to your hands, its uncomfortably hot to the guts of your board and ought to be covered

Epoxy Problems

Q: I have this problem when brush applying a second coat of epoxy over already hardened epoxy. As soon as i have applied it I get these "puddles" that dry out ie. the fresh epoxy retracts itself to leave an awfully uneven finish.
What is this phenomenon / how can i avoid it ?
I have already tried using different types of epoxies without any better results.


A: the problem is "amine blush", a waxy substance that forms a film over Epoxy as it cures. Its as good as a mold release, so you need to get rid of it (sandpaper, or purple pad with water), before applying the next layer. Or - apply the next layer BEFORE the amine blush happens, i.e. BEFORE the first layer has cured completely

Q: I have seen this "waxy" film develop before.
My problem appears also when applying epoxy coats on non treated ply wood and many other surfaces as well (plastic, polyester surfaces, well sanded down epoxy, ...)
Have had a few chemists and local experts diagnose the problem, but aside from comments like "autofobicity" have not had much help.
To get a clean, glass like finish, does one use a "special type" epoxy?


A: "autofobicity" - now there's a good one!
Ok - puddling, fish eyes, all the other unpleasantnesses associated with coatings, Epoxy & otherwise, are due to some contamination or other. If not the amines from a previous Epoxy coat, then how about dust? moisture? ambient, or from the long-suffering tank of your air compressor... How about solvent residue from your wiping things down? oils from your hands? oils from the wood you are coating?
Keep it clean!

Kevlar... is it worth the effort?

Q: I would like to ask you some questions about working with Kevlar ...

I have a board in the shed that has an absolutely mashed nose done by a friend with a useless spock attempt. I (perhaps stupidly) have offered to do the repair.

The nose is split straight down the middle to about a foot (so we are talking a big repair). I was going to glass sandwich the underside as I normally would for such a repair. However, I have recently been given some heavy weight kevlar by another friend and would potentially like to trial the kevlar on the deck of the nose repair 1. to see if I can use it and 2. to try improve the impact resistance of the nose in light of the fact he will almost certainly try another spock! Should I bother or should I stick to glass?

I have heard tell that Kevlar for the wannabe repairer is nigh on impossible to work with (and for this reason I have not used it before) are there any tips you could give me to make the whole experience easier?

My plan was to vacuum a layer of kevlar on the deck of the board along with a standard glass sandwich i.e. glass/airex/glass/kevlar/glass

Does this sound about right or should I be using it on the hull too?

In light that the kevlar cannot be sanded back following lamination how do you get it nicely faired in with the original materials?

A: I hate it I hate it I hate it!!! Kevlar is such a pain! and noses get damaged, anyhow. So I go with regular glass laminations, and then add padding.
If you insist on the Kevlar: grind a pair of scissors to an almost square edge (and be prepared to re-sharpen after 2ft of cutting Kevlar...). Bury it deep under some fiberglass, so that under no circumstances will you have to sand it.
yuk!

 

fin gashes in surfboard rail

Q: I got into a fender bender at my local overcrowded beach break. A board shaper who happened to be in the parking lot told me that these cuts were small enough to fix just by filling them completely with 2-part epoxy, covering the cured patch with a little cloth and resin, then painting with acrylic.

What's your assessment? I don't think the damage reaches as far as the fin box, but I can't tell without some surgery. I want to fix this properly, structurally and aesthetically, but I'd like to do it myself. Living here in NYC my work space is basically the sidewalk in front of my apt. building, or the beach parking lot, so I have to keep things simple.
can i fill the gaps with epoxy and call it fixed? or do i really need to undertake a more complete repair such as that shown on the Repair Basics page, which is the closest thing i can find on the site to my board's damage.

btw, as for testing presence of water, taping a layer of plastic over the holes and putting the board in afternoon sun yielded a few microscopic droplets of water, but not a general fogging of the plastic.

 

A: to simply fill - or to rebuild with Divinycell depends on
1. where exactly in the board this cut is located; and
2. what sort of finish quality you expect from your repair.

as to 1.
if located in the middle third of your rail fore & aft, it is imperative that your repair moves the same way as the surrounding, original material. It should therefore be reconstructed using like materials, i.e. I replace the broken stuff with exactly the same bits, layer by layer.
If located near the ends (such as your gash), board flexing is almost non-existent, and you can get away with a more "basic" approach.

as to 2.
all the materials in your board expand & contract with temperature and air pressure changes. If you introduce a big blob of an "alien" substance (such as a chunk of filler into a collection of layers surrounding Divinycell), then your big blob will always stand out.
If that is ok with you, go right ahead!