I know this has been coverd before, but I couldn’t find it in the search. I’m currently making a 6’ x 21 x 2 1/2 thumb single fin. If doing a 6x4 deck, does the 6 go under the 4? or vice versa? I’m sure it can be doen either way, but I want to know which is stronger. I’m thinking that the 6 should go under the 4, but that doesn’t give the rails the same strength as it would if the 6 wrapped around.
If you want more glass on the laps, do 6 on top, if you don’t then do 4 on top
So it really makes no difference. Ok
I think you'll do better with 6 on top of 4. 4 oz cloth typically has a tighter weave. I was taught to use 6 on top as it has a looser weave, making it easier to squeegee out excess resin. This formula has worked well for me over the years.
it is an easier wet out to put the 6 over the 4, but a 4 top cap makes for a much thinner hot coat
Thanks all for the replies. I think I’m going to go with the 6 on top just so that my rails get the extra glass. I bladed them out a bit.
You know what? Just do 3 x 4 oz layers. More strength, less resin.
not that my imput is of any value,,, but you get it anyway,,,,,
6oz first wraping to the otherside then 4oz with ziplap at rail apex
Kensurf,
Your input is of value, as is everyone’s. That’s why I’m here.
Curious to the reasoning by this? Getting the 6oz on the rail, I get that. But the 4 on top ziped to the rail apex. I guess that just makes for a deck patch of sorts and cutting down the resin like mentioned before. yeah?
Balsa,
That is a very good option. I have plenty of 4oz and would have to buy the 6oz. Would I lam a triple deck lam?
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Kensurf,
Your input is of value, as is everyone's. That's why I'm here.
Curious to the reasoning by this? Getting the 6oz on the rail, I get that. But the 4 on top ziped to the rail apex. I guess that just makes for a deck patch of sorts and cutting down the resin like mentioned before. yeah?
Balsa,
That is a very good option. I have plenty of 4oz and would have to buy the 6oz. Would I lam a triple deck lam?
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You're not asking me, I wrap the 4 oz to the bottom and trim there. That gets you plenty of glass on the rail. As for an all 4oz glass job, if that's all you have, that's what I would do. If you're glassing PU, then I would say go with a double 4 with patches where the feet go, or a double with a 2/3 deck patch. If it's 2 lb EPS, then I'd go with a full triple 4 oz. That's plenty strong and still light.
Unless you are worried about a little extra weight, a little stiffer board, but a lot more strength - I like to wrap two layers from each side on the rail… four total… Now you won’t get those rail dings so easy…
If the four oz is all you got. go with it. Jim ain’t a genious for nothin… good point.
just different ways to skin a cat
all are good methods
the more wrap the stronger as Talor0 said
I’m actually not worried about the extra lil weight. I used a USBlanks Orange 6’2A. My previous boards had really weak rails, so I may just do that. Mostly tail crushes. This board has really thin rails for me anyway. I wanted to try them out. I’ll try and post some pics tomorrow.
I wrote about the three 4 oz layers because that’s what I will do when people ask for more strength without adding weight. I usually glass all longboards with a double 6 oz on top, so a triple 4 will be almost exactly the same in weight (even, maybe, a tiny bit less because of the tighter weave) but you will notice a difference in strength; what I do is cut the first layer at the rail apex, the second layer overlapping, say, about 1", and the third overlapping about 2"; This limits the step on the bottom or at least makes it more progressive. This being said, laminating three 4 oz at once can be a bit tricky as compared to 2 x 6 oz, but it’s still perfectly possible; take your time. Maybe you’re using UV poly? That would be the way to go.
yep, using uv poly. I was also thinking the same as you described, step each down progressivly to eliminate the bump in laps
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I wrote about the three 4 oz layers because that's what I will do when people ask for more strength without adding weight. I usually glass all longboards with a double 6 oz on top, so a triple 4 will be almost exactly the same in weight (even, maybe, a tiny bit less because of the tighter weave) but you will notice a difference in strength; what I do is cut the first layer at the rail apex, the second layer overlapping, say, about 1", and the third overlapping about 2"; This limits the step on the bottom or at least makes it more progressive. This being said, laminating three 4 oz at once can be a bit tricky as compared to 2 x 6 oz, but it's still perfectly possible; take your time. Maybe you're using UV poly? That would be the way to go.
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Curious if you do the three layers of cloth in one shot or do you laminate in stages. Getting three layers of cloth to wet out all at once without problems seems like it would be a nightmare.
On a side note, wouldn't a deck be stronger and lighter if you laminated each layer one at a time? I usually do a double 4 or a 6 + 4 and laminate in one step but I'm wonering if you laminated the 4 and then put the second layer on top of that if you would wind up with less resin in the weave and an overall lighter and stronger lam.
The coin has already been called, but just to add my 2 cents also – if you want to split hairs, the 4oz on top would be slightly stronger structurally, but it is much harder to squeegee all the resin for 6oz through it… – The 6oz goes on top like SurfThis and everybody else has said.
what if like mako said you do two layers one at a time -starting with 6oz then 4oz on top. that would eliminate the wetting out issue and the 4oz would make for a stronger deck???
If you want a stronger board don’t waist your time with 6-4 or 4-6, use good fiber: multiaxial pattern, flat or no waves for minimal crimp, tightly woven or stitched and good resin. Twist open plain wave is the low performance fiber you can find in composits. One day I show some HEX471 to a guy who work in airplane composits he laughs and he give me some tight flat twill, almost impossible to work with (with traditionnal surfboard glassing way, he laughs too…) but so better, nothing comparable.
Sorry for my english
I tried not to respond, but I can’t help myself.
I’m with Jim on the 4 oz on the outside for a lighter board with a thinner fill coat. And if you are using epoxy, a 3 by 4 oz lam stack is not hard at all.
I had a conversation a few years back with Hank at GraphiteMaster. He talked about interlaminar bonding (a good thing) when you lam all the layers in one shot. If you did 3 layers of 4 oz all separately, it would not be as strong and would require more resin. Think about G10 layups. I know they are done under pressure, but multiple layers of ligher cloth gives a stronger panel. I conclude that a 3 by 4 is stronger than a 2 by 6.
Hope that helps.