## vacuum bagging

plummet
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### Re: vacuum bagging

downunder wrote:Andy,

The moment of inertia is I=m*r^2 (2.5kg board with 0.68 radius, and 4kg board with same radius is
73% more inertia).

The heavy board might twist your ankle with a significant force if you stuff up even a small jump and your foot slips of bindings. Or don't jump, transition or anything other than lawn moving:)
Just yesterday I've met a guy with 8y experience and he broke his ankle 2mths ago.

1-1.5 difference is huge. As BWD says, the target should be 2.5-3kg max.

I believe you over reacting downunder.

None of my boards are under 3kg. In fact my big wheel landboard is 9kg! Thousands of boosts hundreds of super powered sessions riding up to triple head waves many many crashes a later and no broken ankles!

Sure a light board is nice. But is not a requirement. Everybody has to start somewhere. And starting with some slabs of ply is a good way to get into board building.

Of course a heavy stiff flat plank is not going to ride chop very well. But man it will rocket upwind.

sijandy
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### Re: vacuum bagging

plummet wrote:
downunder wrote:Andy,

The moment of inertia is I=m*r^2 (2.5kg board with 0.68 radius, and 4kg board with same radius is
73% more inertia).

The heavy board might twist your ankle with a significant force if you stuff up even a small jump and your foot slips of bindings. Or don't jump, transition or anything other than lawn moving:)
Just yesterday I've met a guy with 8y experience and he broke his ankle 2mths ago.

1-1.5 difference is huge. As BWD says, the target should be 2.5-3kg max.

I believe you over reacting downunder.
Big time. Plus if your landing one footed cos you've been prancing in the air doing board offs then you deserve a broken ankle anyway

downunder
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### Re: vacuum bagging

Plummet

we do know you're a big guy:) What's your weight? 80-100kgs? Duno about Andy and darippah ...

Now I am 56 atm. Put this in a perspective of your weight. For me a difference of 1-1.5 kg for a board is HUGE. Massive.

To understand the weight issue one needs to be in the same category. I'm featherweight in boxing.

So, from my perspective 2.5-2.8kg is max.

And 1/2" plywood I can't physically bend:) Slap a second ply layer for the rocker and whooping 6-7kg board after FG. Sure, it's a start. Still, one can do better which I suggested.

So, guys all cool. No over reacting, just plain facts. Experiment, but with a care for your body. You only have one.

BWD
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### Re: vacuum bagging

My experience of losing one strap in a jump and badly spraining a toe on landing tells me it is the board hitting the water and acting as a meter long wrench on my toe that caused the problem. Flying through the air dangling a couple of kg of board was painless (that board was alight one incidentally). It took about a year or so for that "kite toe" to heal.

downunder
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### Re: vacuum bagging

Well said BWD: "a meter long wrench".

My recovery? Ah, where to start. Learning how to walk? Twice. Good bless titanium so I do not ring on the airports.
Still enjoying this sport. Boards building too.

plummet
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### Re: vacuum bagging

BWD wrote:My experience of losing one strap in a jump and badly spraining a toe on landing tells me it is the board hitting the water and acting as a meter long wrench on my toe that caused the problem. Flying through the air dangling a couple of kg of board was painless (that board was alight one incidentally). It took about a year or so for that "kite toe" to heal.

Yeah that's my thought too. its not that actual weight of the board that is the potential issue. its the fact that it slices into the water then acts like a sea anchor while you carry on moving. Its the surface area of the board compared to the rider size which is the issue.

Down under. I'm 82kg. and yes of course make a board that suits your size/weight. at 56kg a board you make to do the exact same thing as me will be thinner, shorter and lighter.

downunder
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### Re: vacuum bagging

Sure mate,

doing it right now:
This is the beginning of my Airstyle board

Will have it soon, Saturday maybe?

Stay tuned...

darippah
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### Re: vacuum bagging

downunder wrote:Sure mate,

doing it right now:
DSC00917 (Medium).JPG
This is the beginning of my Airstyle board

Will have it soon, Saturday maybe?

Stay tuned...
Very nice- can you send me info on how to create a vacuum bag along with parts needed?

Thanks!

downunder
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### Re: vacuum bagging

http://www.boardbuilders.co/

http://boardbuilders-forum.1077691.n5.nabble.com/

http://downunderbloghr.blogspot.com

The above is not a vac bag but a rocker (concave) table which uses a vacuum. You need this not a vacuum bag:)

tkettlepoint
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### Re: vacuum bagging

downunder you have some nice boards myfriend , check out your blog... how are your blankets working ? We went out and bought some for our press , best thing we did with the press. I need to figure out how to program it to step it up and back down for some different resins systems.

180 for 45mins and done epoxy strong and hard like a rock.

keep up the great work

Terrie
www.jellyfishboards.com