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Yet another board build . Super light wind heavy pilot special.

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Created by Imax1 2 months ago, 28 Mar 2020
Imax1
QLD, 2676 posts
28 Mar 2020 6:04PM
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In the quest for planing in the lowest knots , I've decided to go out on a limb and put my ideas and money on an experiment . Call it a lock-down project .
My theory is to go long but not too wide , and short enough to fit in the car .
2.9 m long , 83 wide , no rocker 1.5 m from back . 10 mm flat V at front to 5 mm flat V to back . Hard square edges all the way except a little tuck at the front . No cutouts . Liters ? anyone's guess ? I know its going to be a bitch to turn , but it cant be worse than a RB.
All made without vacc bagging , Will combo wet out on bench and on board.
Its going to be big and voluminous but its going to be lighter than a RB .
Im going for toughness as its going to be used and abused a lot for those all to common 10 to 13 kt days.
Anyones prediction on end weight , and , will it work ?
Im taking one for the team.





6 mm balsa-wood stringer . I know its not normal , but i figure it will stiffen the long board and support the mast box and fin box .
Also makes the shaping much easier.
And , if your going to zoom in on the pic on the wall , hands off , she's mine !



Stringer to finished size and laminated with 4 oz glass both sides .



Finished and approved by ball chasing idiot !
325 gm.



Stringer glued between 17 kg EPS .
Ive only used 13 kg before , this stuff is a LOT harder . Way less spongy .
My theory , Because its so much harder ill use less glass under feet. ???
PS : a 250 mm long hot knife is strangely fun , kinda like a slo mo Light Sabre . Way less foam dust







All square at this stage , no V yet.

decrepit
WA, 9935 posts
28 Mar 2020 5:05PM
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Looking sweet mate. Very tidy/clean shed though, you don't get any marks for that!

Orange Whip
QLD, 759 posts
28 Mar 2020 7:28PM
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No, no, no, you're not getting out of it that easily. I did zoom in to Wonder Woman. What gives?

Imax1
QLD, 2676 posts
28 Mar 2020 8:08PM
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The garage is only two months old , give me time.
What do you mean Wonder Woman , what's with that ? The name says it all . I can not lie , I like gold rope . My wife would give me a hall pass

mark62
345 posts
28 Mar 2020 9:18PM
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Select to expand quote
Orange Whip said..
No, no, no, you're not getting out of it that easily. I did zoom in to Wonder Woman. What gives?



Select to expand quote
Orange Whip said..
No, no, no, you're not getting out of it that easily. I did zoom in to Wonder Woman. What gives?



Well spotted, your eyesight is way better than mine

NotWal
QLD, 7378 posts
29 Mar 2020 12:36AM
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Antique radio too.

Gestalt
QLD, 12672 posts
29 Mar 2020 1:01AM
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No comment on the shape but was curious if the density is high enough for a traditionally laminated blank with a balsa stringer.

Mark _australia
WA, 19779 posts
29 Mar 2020 12:04AM
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I say no...... 17kg is very soft still. I used 28kg on surfboards and they need extra deck patch. This needs at least wood lam and glass, or PVC foam sandwich.

Imax1
QLD, 2676 posts
29 Mar 2020 6:58AM
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I forgot to mention , it's going to be 3 mm pvc sandwich construction . Cork under feet.

Tardy
3500 posts
29 Mar 2020 6:07AM
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good on ya for giving it a go.

you asked how many litre ? 140 is a good number if your 95 kgs .

i like cutouts . makes the board feel lighter when on the plane ,also with a slight rail cut out ,its nicer to gybe ...

olskool
QLD, 1756 posts
29 Mar 2020 8:33AM
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Nice experiment build there Imax1. Been a longtime in the think tank. Q. Does it need to be so wide (83) if its 290 long? Other SLW thingys are as wide but only 230-240 long.

Imax1
QLD, 2676 posts
29 Mar 2020 8:37AM
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I was thinking of cutouts and some rail tuck , but this board is purely to get planing earlier . Both will hinder the planing threshold. I'm presuming I'm correct in that thinking . Please let me know if that's not true . Cutouts would give a better ride and rounder rails will make it more user friendly.
I have other boards when the wind is over 13 kts.
My gestimate , around 200 litres.

Imax1
QLD, 2676 posts
29 Mar 2020 8:48AM
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olskool said..
Nice experiment build there Imax1. Been a longtime in the think tank. Q. Does it need to be so wide (83) if its 290 long? Other SLW thingys are as wide but only 230-240 long.


SLW thingys are between 90 to 95 cm.wide and designed around a 85 kg rider .A formula board is 1 m wide . I'm 115 kg. So I need extra . I want to give it every possible chance . Just not sure if I can go too big and have a negative effect .

LeeD
1452 posts
29 Mar 2020 7:06AM
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Only negative is early planing with limited top speed.

Imax1
QLD, 2676 posts
29 Mar 2020 9:21AM
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LeeD said..
Only negative is early planing with limited top speed.


Do you think it's too big for ultimate early planing ?
Im not worried about top speed , I wouldn't want to go too fast on it

olskool
QLD, 1756 posts
29 Mar 2020 10:03AM
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Imax1, a must in design spec for where you sail is shortest fin possible. No? Dont want to miss a day on the water!! 290 length gives you that by using parallel rail length n shape. Going wide means bigger fin.

Imax1
QLD, 2676 posts
29 Mar 2020 10:20AM
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olskool said..
Imax1, a must in design spec for where you sail is shortest fin possible. No? Dont want to miss a day on the water!! 290 length gives you that by using parallel rail length n shape. Going wide means bigger fin.



I know , I'm torn . Hoping Fangys big fin will be enough . There are guys here using 90+ wide and shallow fins . Mines a skimpy 83 wide needle.
Could add extra side boxes later for those really shallow days if I'm loosing too much grip.

Tardy
3500 posts
29 Mar 2020 9:11AM
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I Had a 130 Titan ..it was 84 wide ..never felt too wide though ,but had a narrow tail .great gyber ...and was great in 12 -13 knots .
if your 115 kgs ,you will need foam .

DELTA make a 30 shorty ..i have one ,but its too much fin for me ..it never slides out ever...might be what your after ...

interest to see the final master piece ..

Gestalt
QLD, 12672 posts
29 Mar 2020 11:35AM
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Mark _australia said..
I say no...... 17kg is very soft still. I used 28kg on surfboards and they need extra deck patch. This needs at least wood lam and glass, or PVC foam sandwich.


Thats my take on things too.

Pu blanks were 36kg. Eps comes in high density as well.

Stringer seems very light to me too.

So. How much carbon can you throw at this imax

Gestalt
QLD, 12672 posts
29 Mar 2020 11:36AM
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Early planning require width when designing planing hulls. There are ratios that can be applied. Length isn't going to help.

Gestalt
QLD, 12672 posts
29 Mar 2020 11:48AM
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Cutouts are used to change angle of attack of the board when planing. With planing hulls the tail lifts at speed so cutouts are used to reduce lift and stop the nose from being forced down.

With displacement hulls the opposite occurs the faster they go the more the tail sinks.
I forget the full theory but from memory using round rails up front on displacement hulls allows the nose to trim down.

Imax1
QLD, 2676 posts
29 Mar 2020 12:43PM
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Select to expand quote
Gestalt said..

Mark _australia said..
I say no...... 17kg is very soft still. I used 28kg on surfboards and they need extra deck patch. This needs at least wood lam and glass, or PVC foam sandwich


So. How much carbon can you throw at this

Select to expand quote
I'm going to stay with glass and use carbon inegra patches at mast base , fin box and the nose of the board.
one layer 4 oz over blank , then two layers over sandwich , another layer of top from in front of mast to back , extra under feet . Each layer overlapping on rail .
That should do it.

Gestalt
QLD, 12672 posts
29 Mar 2020 2:10PM
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How do you hold the sandwich onto the core if it's not vac bagged. Wont you end up with air pockets?

decrepit
WA, 9935 posts
29 Mar 2020 1:01PM
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I've never tried it, but a mate of mine made a jig so he could stretch elastic bands (old bike inner tubes?), over the board. He reckoned it works OK. Not sure how good it would be on very flat sections though. May need a foam mattress over the top, to spread pressure down.

Of course with the same foam mattress, you could just weight it down evenly over the board. May be hard finding a mattress long enough though.

The other way is water pressure, if you have a big enough tank, (swimming pool) a water tight plastic bag, (vacuum bag), and a system to sink board to required depth. I tried this once on a small project, but sharp edges punctured the plastic, and the curing resin was saturated. Fortunately epoxy doesn't mind water anywhere near as much as Polyester. it did go off, but went very milky.

If you do the swimming pool thing, the submerging device would need to pull evenly over the board, otherwise distortion could occur.

jirvin4505
QLD, 1055 posts
29 Mar 2020 3:28PM
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I've got plenty of Vac bag stuff if you need it

Imax1
QLD, 2676 posts
29 Mar 2020 3:29PM
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Gestalt said..
How do you hold the sandwich onto the core if it's not vac bagged. Wont you end up with air pockets?


Top is easy because it's curved . I take the sandwich as close to the edge as I can bend it , then pull down with tape all over .
Bottom is as decrepit says , with a camping mattress with pavers on top . One side at a time . It's a flat V so shouldn't be a problem .
The rest on the rails I will contact glue 3 mm HD EVA. I've done this before and works a treat. Super tough almost ding proof rails

Imax1
QLD, 2676 posts
29 Mar 2020 3:38PM
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jirvin4505 said..
I've got plenty of Vac bag stuff if you need it


Mmmmm , thanks Jeff.
I did say to myself I'd get a vac system for my next board . But I seem to do ok without it. It would save a bit on board weight. I do like to overlap rails , so I'd be bagging quite a few times.

fangman
WA, 923 posts
29 Mar 2020 2:37PM
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I was going to say something worthy but damn! I got distracted by Wonder Woman and now can't remember. In WW happy place now

Gestalt
QLD, 12672 posts
29 Mar 2020 4:42PM
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Imax1 said..

Gestalt said..
How do you hold the sandwich onto the core if it's not vac bagged. Wont you end up with air pockets?



Top is easy because it's curved . I take the sandwich as close to the edge as I can bend it , then pull down with tape all over .
Bottom is as decrepit says , with a camping mattress with pavers on top . One side at a time . It's a flat V so shouldn't be a problem .
The rest on the rails I will contact glue 3 mm HD EVA. I've done this before and works a treat. Super tough almost ding proof rails


good one. look forward to seeing you out on it when the world returns to normal.

decrepit
WA, 9935 posts
29 Mar 2020 3:34PM
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Had to put my glasses on but I finally found her!!!

decrepit
WA, 9935 posts
29 Mar 2020 5:37PM
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Gestalt said..
Early planning require width when designing planing hulls. There are ratios that can be applied. Length isn't going to help.


Not sure about this Gesty.
Theoretically, width with a big fin is more efficient in light winds when planing. It has a high aspect ratio lifting surface, so less drag.
The other advantage of width, is being able to control a big fin.
However, for early planning the hull has to function efficiently in displacement mode. Here length is the key, long and narrow is better in displacement. The hull is at less of an angle when climbing over the bow wave, and this is amplified in shallow water with ground effect making a bigger bow wave.

But I could be wrong of course



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"Yet another board build . Super light wind heavy pilot special." started by Imax1