first fish, first sandwich, first board, first round of questions ...

General Discussion
1

Finally have the time, materials and tools together to start on this project,

making templates and hotwiring foam starts tomorrow:

It’s actually 6’6", AKU starts the tail about 1/2" past the origin, which changes the measurement. Wide point is 5" ahead of center.

The tips are 12" apart with a 6" crack. Flat bottom and I’ll be putting a concave in the deck from the crack up to about 8" from the nose.

Why so big? This will be my first shortboard, transitioning from a 9’6" Stewart HH. At 200 lbs I can push my girlfriend’s Southcoast 7’6" egg under chest high surf (wouldn’t call it a duck dive at my proficiency level, but I don’t end up back on the beach) so I’m aiming for a similar volume. Plus I’ve had some shoulder issues that make me want to put the emphasis on wave catching/paddling. I want to plan it for small beach break (knee to chest high), and for speed over acrobatics. It will end up on larger waves/reef breaks, but that’s not where it will live.

Right now it’s a glued up block of 1lb insulfoam. Speaking of which: I used 3M 6070 to glue the layers. A few posts mentioned trying 6070 but I haven’t seen any reports on how well it held up. It’s a web-type spray adhesive, and the web only spreads out about 4" wide and globbed up occasionally, so light and even coverage it wasn’t. I had about 110 sq ft to cover (both sides for each join) which used up most of the 8oz can. Is 3M 78 a better bet? I’ll yank apart an offcut tomorrow and see if the glue is stronger than the foam.

Skins: 1/8" balsa, sanded down a bit, with varying layers of 4oz glass on both sides, and RR2000 all around. Rails will be built up from balsa as well.

Rails: I need to spend more time looking at fish in the water/in shops/on the beach, not just on the forums. The slices in the pic are a start, but I need to work on them.

Fins: I like the idea of putting in a twinzer setup, but for now I’m going with a low-cost twin keel setup and then later on decide if the board is a candidate for boxes and more fins - or if I should just wait til the next board. So I’m going to inset a few big ovals of d-cell under the balsa where boxes may go eventually, but glass on either Hobie fish fins or Beatty rocket fins(7.4" base x 5.4") with a little toe and cant.

Advice: is appreciated!

2

Nice shape mate. My TK fish is wider and thicker than i really need ( 22’’ wide 3’’ thick ) but i really love it for easy paddling and catching small waves, like knee to waist. But you’ll find you can also surf it up to a foot overhead, bigger if they aren’t too hollow, and im only an intermediate surfer. Fun Fun Fun!!!. I think you will enjoy it a lot, keep us posted.

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hi. On my extensive experience of ONE compsand fish, I dropped the volume alot compared to PU fish and retained good wave catching ability because the compsand is so much lighter.

Karl

4

sofa seater

if you weigh 200 lbs, make your deck skin super hard

  • try 1/8balsa with an EXTRA 1/8 underneath with glass, that will give you something that will hold up with all your weight.

Apparently [only 90% sure] thicker wood does dent, which is plausible… you can do this as patches to avoid weight. Or add the D-cell underneath. you WILL kill the board real soon otherwise, i did on my first too., reinforce, spread that load.

for shape, i like the looks, round rails are fast, the pic is small on my screen, are those rails low a bit?

Keels put on straight are fast but turn diddly with low rocker. So maybe try and make twin-like plywood fins? I like that better, but maybe i manoeuvre more than you.

where are the pics?

Wouter

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Hi Wouter,

Thanks for the advice. I’m going to make a little test panel with a few different laminations to see which handles the most abuse - and to test the vacuum press rig. To keep the balsa from eventually getting crushed, is it worth wetting out the fiberglass directly on the balsa instead of on a wetout table for both the inside and the outside layers? I don’t mind trading extra weight for greater resin penetration. I am planning on having the rails lower and with a bit of an edge towards the tail of the board - not a good idea with this shape?

Seems like putting up a thread saying “I finally have time to start on this project!” is a signal to the powers that be that you really need more crap in your life to take care of. So I haven’t made much progress in the past week, just the first hotwire cut and putting in some d-cell inserts for possible finboxes.

The hotwiring went smoothly, except for one gouge (I slowed down) that you can see towards the bottom of the pic. Will fill that before putting on the bottom skin.

As for using 3M 6070 for glueing up 1lb eps blanks: meh. If you pull apart two layers they pretty much come apart at the glue line without much foam breakage.

6
Quote:

Seems like putting up a thread saying “I finally have time to start on this project!” is a signal to the powers that be that you really need more crap in your life to take care of. So I haven’t made much progress in the past week, just the first hotwire cut and putting in some d-cell inserts for possible finboxes.

The hotwiring went smoothly, except for one gouge (I slowed down) that you can see towards the bottom of the pic. Will fill that before putting on the bottom skin.

As for using 3M 6070 for glueing up 1lb eps blanks: meh. If you pull apart two layers they pretty much come apart at the glue line without much foam breakage.

To keep the balsa from eventually getting crushed. WITH MAX VAC, or 1.0 BAR od 100Kpa OF PRESSURE IT WONT EVEN LOOK DIFFERENT.

is it worth wetting out the fiberglass directly on the balsa instead of on a wetout table for both the inside and the outside layers? NO, BUT>>>> MY ADVICE [only 3rd compsand soon] is to 1.st - tape balsa together 2nd - put the inside glass on mylar, polyethylene, whatever plastic, wet out 1.00 weightglass : 1.05 weight resin. ADD BALSA ON TOP tape facing up [folded edges to remove easily] , add plastic with airholes and breather on top [you can reuse this] cover up suck max vac [eventually add heat in box] this gives you good skin. This will suck resin to the place where the air is removed by the vacuum. before adding skin, you can spackle blank, to improve dent resistance. i used 2mm skin, and resin went straight through the balsa, also where joints were. Then when rails are on, vac skin on, with wood on outside. Once skin is on, pretreat balsa with impregnation resin, especiallly the joints., and lam as usual directly after. if you want to add patches, add them ON TOP of skin, not underneath. try out compsand, or my 2nd post on this site. I don’t mind trading extra weight for greater resin penetration. I am planning on having the rails lower and with a bit of an edge towards the tail of the board - not a good idea with this shape? HARD RAILS ARE FAST.

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Absolutely love this thread, you’re about 2 weeks ahead of me on exactly the same thing! I’m an old fart hoping to move to a shorter board after 9’4" and 7’, got to give it a go while I still can (just!).

Just cut the outline and am about to do the rocker, no hot knife so will have to plane it all.

Like you I experiment a lot. I’m currently playing with infusing the whole brute in one go but fear the foam will suck up too much resin.

I await your posts with bated breath and great enthusiasm

Rik

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Hey sofa (interesting name, why?)

I have a fish just about exactly these dimensions if you want to try riding one, see what you think about the rails, fins, etc. It’s old school construction but still might be worth checking out even if you’re doing eps/sandwich etc.

I like my 6’6 fishes, so does LeeV, and so do two other friends in the neighborhood. They are all a bit different interpretations, different fin setups, etc. We’ve done 2, 3, 4 fin versions and all have their good points. With probox we’ve swapped out keel fins for MR-type twins, etc etc etc. I personally like smaller side fins and a little center fin best! (yes I know, sacrilege! center fin on a fish - ha ha.) But the twins and quads are fun too. Go very light on the toe-in if you use long base twins though…

have fun with it!

K

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do you mind sharing your thoughts on how the ride on the 2, 3 and 4 fin set ups differ on the fish?

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wow - seems like someone always feels like their ox is being gored with comments like these, but here are My Personal Opinions (others will certainly have Their Own Opinons on this comparison…so take with a grain of salt please!!!)

2 fin - like any twin fin, can tail slide when you’re not expecting it (eg big bottom turn), can be “tracky” but a lot of fun. Behavior varies w/ type of fin and placement, of course. I hear a lot of guys say its hard going backside on trad fish setups, but I suspect that’s board width as much as fin choice (gotta get your heel over by that rail.)

3 fins - the way I set mine up (tiny trailer & stiff medium size side fins w/ toe and cant) less like a twin in that the tail won’t tend to slide out quite so soon when you crank it over on rail (unless you’re trying to), albeit w/toed in fins will feel like a bit more drag than twin or quad but initiates turns a bit quicker too. snappier.

4 fin - drivey down the line, fast when pumped, again depends a lot on your choice of fins and fin placement, can be more of a twin feel or more “modern” if you get my drift…

hope that helps, YMMV (your mileage may vary). Maybe you can get PlusOne to chime in here, he’s a fish builder from way back as I recall… you can play w/ bottom contours too, so many combinations to try…they are all good, they are all fun!

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Hey Sofa, is that a hotwire stretched across the eps and resting on the template? Does it unfold or something? Thanks!

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Hi Keith-

Thank you for the offer! For some reason I didn’t get any of the “Swaylock’s Discussion - Reply to your post” messages for a while, and didn’t see that there was still activity on the thread. I’ll PM you if that’s OK.

As to Sofa: after lurking for a while, I finally got a login for Sways last fall when I was out of the water for a while trying to resolve some shoulder issues … and feeling grumpy that all I was surfing was a sofa.

Thanks for the tip on the toe in for long base twins,

will have some updates in a bit.

13

Nope, it’s just a clamp/tool guide. I’ve seen some pics of folding ones, but my hotwire bow is the standard DIY bits of wood, eyebolts, and a spring. For now the spring has been repurposed:

a syringe, a momentary-on pushbutton switch, and a spring make for a cheap vacuum controller.

Quote:

Hey Sofa, is that a hotwire stretched across the eps and resting on the template? Does it unfold or something? Thanks!

14

Hey Rikds,

how is your board coming along?

I finally have time to get mine going again:

the bottom went into the bag last night. A six dropcloth cube and a bathroom heater fan kept the temp up well enough, though the girlfriend thinks the garage looks like a scene from Dexter. Most of the tarps are taped to PVC pipes at the bottom, so they can be rolled up and tied overhead and out of the way.

15

Hi Sofa

Progress a bit slow of late, lack of space and time! However have planed the bottom to near it’s final shape. First go at EPS and finding it more of a problem than expected. Doesn’t sand like PU and getting the bottom contours right is hard for a first timer.

However have found a source of great balsa (at an outrageous price!) and once negotiations are complete will move on to skinning the bottom.

Am looking at a PU blank from Homeblown (UK blank company!) which will become a similar board by resin infusion a lot sooner than the compsand. Be interesting to compare the 2 once done.

Keep the thread going, it’s great.

Rik

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Hey Rikds have you thought about a rocker table and bending the eps rather than trying to plane, ok some say this puts stress on the foam but ive never had any probs, and by the time youve thinned out the nose and tail sections theres very little resitance left in the foam…

Get some pics posted…

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Gotta love that vacuum controller - much more sterile than an auto vac chamber :slight_smile: .

Do you find that its a fairly repeatable cycle for on/off pressures?

Cool thread – Thanks – Its all getting me closer to jumping into my first shape / compsand.

yoyo

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The syringe vac controller has been pretty well behaved; once you adjust the spring the start/stop pressures don’t drift overnight, and it doesn’t leak.

It’s also easy to adjust the dead space between the start/stop pressures. When I first set it up, instead of chasing down a luer lock connector with a hose barb I just used a needle poked into the rubber hose connecting the reservoir to the vac. gauge. That connection held up so well I decided to just stick with it. A 26 ga needle lets air through so slowly that the pressure in the syringe is “chasing” the vacuum in the reservoir for quite a while after the pump is turned on, and the resulting dead space is huge. A 22 ga needle brings it down to a spread of about 5 in Hg, and an 18 gauge almost halves that. Putting the controller inline between the pump and the reservoir instead of attaching it to the reservoir cuts the dead space down too.

It’s only had about 24 hours of use so far; like most kluges I don’t know how well it will hold up. The 15 amp switch cost $6 at an electronics supply store, so it’s cheap. Cheap unless it fails in the middle of the night, that is…