Fibreglass and resin sales in welshpool have pretty much everything except specific windsurfing gear like fin boxes etc. I go there because its easy to get all the gear from one spot. There are more specialist places for certain products which are usually cheaper but sometimes you have to buy more gear than you need . (ask bluejuice he should know )

jim

Thanx Heaps

Hoop & Leski



Decrepit is an experienced board maker, has vacuum eqip, I'm the apprentice

Need a name for baord, what do you reckon about a forum competition with $ prize for best name

Hardie SoftBoy

how bout we get a free board..

hmm a name how about.. uneven unco board.. lol.. no wait i can come up with something beter..

Decrepit-hardon..

lol

I LIKE WATER

Decrepit

Just remember, when you are doing the Harides wave,frestyle slalom formula crossover beastie.

You'll Probably feel a bit like doctor Frankestien, going "What have I Done" He'll probably reak as much havoc in the water as well

That it still leaves the ELMO panel beating rack free for my regular repair appearance

See ya next in the water

Elmo

Regularly exceeding my capabilities

quote:

---

Originally posted by decrepit

Elmo,
The only thing taking up your spot in the racks is an ancient Cordingley mal, even more decrepit than me. Would you like to find a new home for it???? I've been tempted to cut it in half and throw in the bin, but my anti sacrilege circuit keeps cutting in and prevents me.
Any body want an old mal, needs HEEPS of work.



decrepit

---

Give It to da hardman, pay him to take it. it's got to be better that the humiliation he will recieve when he takes his goat boat out into the line up

Thanks for planning re my repair space, it looks like the nose rienforcing is working, haven't managed to damage it using mast and boom, have now resorted to using body parts to do the damage

Life is but a dream, from which we all must wake.

I just picked up some more resin from Barry this am and I asked does he mind me putting his name & phone number on the internet and it's OK with him.
So if you want some of the best epoxy resin and I have tried west systems, sb112, K36 etc Call Barry on 9446 6159 he used to supply the resin for windtech sailboards, and Dan E's (KA18)sailboards.
I get less pin holes, less blush build up, generates less heat than the others and is a dream to laminate with.


a.k.a. KA202

I haven't actually seen any data figures on its hardness, I would say it feels very similar in hardness to west systems and the sb112, Ive made quite a few boards and never had one break yet.
Aramid has poor compression qualities and most boards fail when under compression I don't think you will gain much say using 6oz aramid against 6oz normal glass also It's a b*tch to cut up and in repairs it's a b*tch to sand, it's also not very stiff. It is good for stopping bullets if you use enough layers. (I don't usually have many gunfights while I'm out sailing)
Most other custom boards only use 3mm PVC, I think the weight savings from using 5mm to 3mm would only be a couple of hundred grams.
Using carbon will give you great stiffness to weight ratios.
If you have the cash then maybe 4oz inside 3mm pvc and 6oz of carbon and 4oz of glass vacuum bagged on the outside would keep it light and stiff.



a.k.a. KA202

Decrepit

I'm keen on the old Mal - I want to give surfing a go but I don't have a board. If it's still available, leave your phone number on my mobile (0400 028 616) and I'll make arrnagements to collect it from you.

From my personal experiences in building foam/glass dinghys and my materials engineering knowledge, by not bagging the outerlayer of ur boards u are simply adding dead weight to the board coz most of that excess resin does not support any load.
There is a resin to glass ratio which depending on the material properties of the glass and resin will give the best stiffness to weight ratio. Any extra resin might improve impact resistance slightly i suppose but at what price!!! i cant remember the figures for the ratio but it is in a SP Systems catalogue from their website.

Yeah i do understand how wraping the rails is a pain but if u put in the preperation then u will end up with a surface that only requires a small amount of fairing then priming and painting. Hey u dont get the blush if u peel ply and bag it .... saves time sanding!

we found to prevent bleeding off too much resin we just had to control the vacuum we were producing.(ie dont use 98kPa vacuum try about 70kPa). but this also depended upon temperature, viscosity and working time.
Oh and are u using peel ply, perf, absorbing layer, non perf, vacuum blanket, bag. and is ur vacuum evenly distributed otherwise u will have diff resin to glass ratio along the board.... u could use this to ur advantage if u want more resin at one end. make sure the blanket doesnt have joins in it and covers the whole board in one piece. the other thing is to make the peel ply sit flat by spending time preping it....there are many tricks to get this to work that are too hard to explain in words here.

Thats my 2 bob worth, comonly known as an incoherent rant.

www.outdoorshots.com.au/view_sessionshot.php?eid=43&pg=6&sid=04p1313110
www.outdoorshots.com.au/view_sessionshot.php?eid=45&pg=1&sid=04p2043521

vacum bagging is always cool as it add a little bit of stress to the board building!!!
but it is always nice to open the bag and unpacked everything..it's like christmas!!!

(providing you 've a good reliable vacum pump and a baog not full of holes then you are fine..no worries)

same here
I used the breather from Resine Sales (cannington) it 's not cheap cheap ..but really thick and does the job perfectly
peel cloth, perforated plastic , breather....
and then not much sanding to do..

From the SP site listed here www.spsystems.com/solutions/general.htm
if u download the guide to composites pdf file it in basic terms will explain a few interesting things. one of them was:

"reinforcing fabrics with closely packed fibres will give higher
Fibre Volume Fractions (FVF) in a laminate than will those fabrics which are made with
coarser fibres, or which have large gaps between the fibre bundles. Fibre diameter is
an important factor here with the more expensive smaller diameter fibres providing
higher fibre surface areas, spreading the fibre/matrix interfacial loads. As a general
rule, the stiffness and strength of a laminate will increase in proportion to the amount
of fibre present. However, above about 60-70% FVF (depending on the way in which
the fibres pack together) although tensile stiffness may continue to increase, the laminate's
strength will reach a peak and then begin to decrease due to the lack of sufficient
resin to hold the fibres together properly."

oh and another interesting point they made was :
"It is also important to note that with metals the properties of the materials are largely
determined by the material supplier, and the person who fabricates the materials into
a finished structure can do almost nothing to change those 'in-built' properties. However,
a composite material is formed at the same time as the structure is itself being
fabricated. This means that the person who is making the structure is creating the
properties of the resultant composite material, and so the manufacturing processes
they use have an unusually critical part to play in determining the performance of the
resultant structure. "

So from this Bluejuice u either sucked way too much resin off when u bagged that board or ur manufacturing technique was not right! Also i read ur website and saw that u put an extra layer of resin all over the board and then sand it off. I dunno bout u but that would really piss me off.... not just the fiberglass dust but the physical effort not to mention the time ur wasting when u could be on the water!!! Carn oldtimer get with the times... we arent building surfboards here. Also if u use more carbon in the top deck then u would be making it less likely to microcrack. Microcracking is related to the adhesive properties between the glass and resin and also the fracture toughness of the resin.

read what the carbonart boys have to say about glass resin ratioswww.carbonart.co.nz/construction.html

Also if u brag about baking the boards while the resin cures, why dont u use prepreg???? not messy easier to get almost perfect FVF etc!!!
I'll get off my soapbox now. I'm not tryin to preach or nuthin but u could be producing awesome boards ppls u just gotta do ya research and experiment ... oh and be prepared to fork out for carbon.
"If everyone bought carbon instead of S glass then the price of carbon would be the same as S glass is now!!!!"

www.outdoorshots.com.au/view_sessionshot.php?eid=43&pg=6&sid=04p1313110
www.outdoorshots.com.au/view_sessionshot.php?eid=45&pg=1&sid=04p2043521

Thanx Hoop, Bertie, Bluejuice, Leski,

Decrepit is rapt in the advice and so am I. Given us inspiration to give the full vacuum bagging a go (Not just bottom).

Grumpy had a look at the rocker profile when at Decrepits and thought too much nose rocker? for a light wind planing board? any opinions? know it's hard without seeing it?

My experience with the really flat early planing boards is they bounce around heaps in the ocean, I'm willing to give up some early planing for more control and user friendliness in the ocean. Any views?

Hardie SoftBoy

Bertie,
What sort of boards are you using in the outdoor shots pics and which one is you with 2 in the picture?

flatus :

A reflex that expels intestinal gas through the anus [syn: fart, farting, wind, breaking wind]

[L., fr. flare to blow.] 1. A breath; a puff of wind. --Clarke.

2. Wind or gas generated in the stomach or other cavities of the body. --Quincy.

Hardman

Not sure exactly what you are seeking, but I'll voice an opinion.

Decrepit showed me a wave style rocker line - curved most the way through the board to improve turning control on waves. The question is how much rocker is enough to give control without buggering up early planing, and do you want turning ability or just to quell chop bounce ?. Your stated design criteria (8'2" or 249cm) long, 70 wide is shorter than most "mainstream" designs for that width, and if it's too curved on the bottom I think it will plough, not plane.

I'll give you the benefit of my own experience of several boards I've owned/ridden in this category. Not sure how your weight compares with me (106kg), but the principles remain.

My first intermediate board was a Bic 283 - 283 long, 69 wide, 150lt, fair rocker, lots of V. Was very predictable in sea, but over 30cms longer than your design and was pretty slow, and the boom smashed the nose all the time, so I traded it. Great intermediate board - if the nose had been a bit shorter would have been better.

Tried a mate's Bic Techno Large - 263 long, 69 wide, 135lt, more rocker than 283, double concave bottom, very narrow tail. EXTREMELY manouverable, pretty good in chop given width, not too easy to get planing due to rocker, short waterline length and narrow tail. I did'nt ride it for long, but wasn't immediately impressed.

Tried a 2004 JP Excite Ride 160. See JP for specs. Felt just like my old Bic but a bit more manouverable, and lighter. Like the Bic, it felt fairly pedestrian, but very predictable. Most the people I know who own one love it - particularly those who don't sail every week and who enjoy the sail, not the speed.

Bought a JP Freeride 129 - 270 long, 70 wide, 135lt. Fast, planes easily. Gave it to a 75kg mate on a 15kt day at Safety Bay a few weeks ago and he fell in love with the speed and early planing. No problems with it bouncing around in the ocean.

I guess my point is you are looking for light wind performance. When wind is light, you inherently get less chop to bounce you around. In light wind you will go slower (the wind is going slower), and getting on the plane is the challenge - early planing matters. If your design has a wave board rocker, a kicked up nose and a short waterline, how well is it going to plane ?

I reckon you give it a kicked up nose so it doesn't submarine, but cut it off square like the Bic Techno Large to keep waterline length up. Make the bottom & tail flat, but consider using a decent V or a double concave bottom (ie Starboard) to smooth the bounce. Adjust the tail width to suit your weight - lighter sailor = less width.

Hope your design is a cracker. It would be an interesting project.