Too stiff and heavy

BbTahoe · Post by **BbTahoe** » Wed Mar 04, 2009 2:55 pm

So I've made around 10 boards, and for the most part, they're great. The one draw back is that they're all stiff and heavy. I know this is really common for home made boards, but I need to fix it. What is the main cause for the weight? Epoxy? Fiberglass weight?

I've been working on making a heat tent for my press so I can make my epoxy more viscous and squeeze more out. Will that do it? What weights of fiberglass are people using? Any other tricks out there?

j-raw · Post by **j-raw** » Wed Mar 04, 2009 3:12 pm

how thick is the core that you're using? That could be a part of it.

MontuckyMadman · Post by **MontuckyMadman** » Wed Mar 04, 2009 3:37 pm

what pressure? what epoxy?
I have giant skis and they are light and stiff but most people say their skis are to soft.

BbTahoe · Post by **BbTahoe** » Wed Mar 04, 2009 3:48 pm

I've been pressing at around 40 psi and using QCM EMV-0049 and ECA-408.

The cores I use seem to be pretty standard - I've ordered them from snowboardmaterials.com and from Sentury.

I'm hoping I can raise the heat and crank the pressure to help with weight.

doughboyshredder · Post by **doughboyshredder** » Wed Mar 04, 2009 6:32 pm

I personally think that the main key to a light board is using as little epoxy as possible, and squeezing as much out as possible. Not using full wrap edges also helps some. I am using 19oz triax with cf and kevlar reinforcement. I think 40psi and no heat is probably causing there to be more epoxy than necessary left in the laminate. I am pressing at about 70psi. My boards are not exceptionally light imo, but they are definitely not heavy.

BbTahoe · Post by **BbTahoe** » Wed Mar 04, 2009 6:38 pm

I don't want to waste any more time or materials. I'm pressing a few boards this weekend and I'll crank up the pressure and see what happens.

Thanks for the help guys!

Head Monkey · Post by **Head Monkey** » Wed Mar 04, 2009 8:04 pm

Weigh all your parts and see where your weight is going. Here’s a real example, all weights in grams, and all but the foil weight are final in-board weights:

Base and edges: 615
Foil: 25
Core: 919
Inserts: 69
Glass: 634
Epoxy: 485
Top sheet: 312
Total final board weight: 3059

This is typical of the boards I build, and the core is the greatest single weight. You won’t find any savings in your base, top sheet, and inserts. Any savings from edges will be pretty small. Your options are really a lighter core, lighter glass, or less epoxy. I’m guessing you’ll find that you can’t adjust your final epoxy weight by more than 25%, which results in a pretty small overall weight adjustment. Your real opportunities are in the core and glass weights.

You can weigh a lot of that stuff directly, but to get accurate glass, epoxy, and top sheet weights you need the area of your board. I don’t know if Snocad gives the board area, but if it doesn’t it should be an easy addition, and someone should ask for it to be added.

Hope that helps!

rockaukum · Post by **rockaukum** » Thu Mar 05, 2009 4:27 pm

Mike,
Speaking of glass... What is the glass you are using? 19 or 22oz triax?

I am thinking of a board with 22 on the base and a lighter biax on the top. Will not be using a top sheet (as of now) and plan on sealing it with a poly urathane. Last board was "too heavy" per my son... Any help or information would be great.
ra

Head Monkey · Post by **Head Monkey** » Thu Mar 05, 2009 8:25 pm

Rockaukum, I use both 19 and 22oz triax, though mostly the 22oz. The board above had 22oz.

Craig · Post by **Craig** » Thu Mar 26, 2009 4:18 pm

Rockaukum, If you don't mind spending a little bit more, you can try S-glass (or maybe aramid), I've found them to give the slightly better strength to weight that can make a difference. If you stick with E-glass, I think you're on the right track switching to a lighter biax. Maybe you'll sacrifice a little longitudinal strength (this might not be a bad thing at all), but be fine, if not stronger, torsionally.

rockaukum · Post by **rockaukum** » Thu Mar 26, 2009 7:04 pm

I just profiled the board today. It is 6mm at the bindings. I tapered it down to 2 at tip and tail. Between the bindings I tapered it down to about 5mm. I will try going with the triax top and bottom and press at about 60psi. Have to wait for my son to do his graphics so the pressing will be next week or so.
Craig, I will look into the s-glass or aramid. unfortunately I just got my supply of triax from raka. My hope is reducing the core size and higher pressure will bring down the weight some. This will be a rockered board too.
ra

hugocacola · Post by **hugocacola** » Fri Mar 27, 2009 6:38 am

How many kilos have your boards, because the main reason that the board been so heavy is all about wood... my boards has about 2.8kgr i think if they have 150 more or in total 2.95kg that will not make any diference when you are in the air...speed that what is need to fly more...electra bases always sintered... and also a good mix of fiber glass...

knightsofnii · Post by **knightsofnii** » Sun Mar 29, 2009 3:14 pm

I'd rather have a board come out a couple oz heavier, than have half my boards delam because i didn't use enough epoxy. I probably use a bit too much, to ensure that every single nook and cranny in that damn thing is saturated.

Is your press heated? the heat helps initially liquify the epoxy to squeeze it out.....then it comes out a bit and BAM, solidifies...so it might be good to ramp the temp up to your desired setting so that it doesnt kick too soon. I get everything settled in the press first then turn the heat on once i hit 60psi.
We've been pressing around 75psi. The reason we do this is due to how our press came out, at lower pressures it doesnt like to conform to nose and tail shape well.

Almost all the epoxy squeezes out right at the "contact points", where nose and tail are widest. These are the lowest parts of the mold, so that's wehre it all heads to due to gravity.

Imagine you could press your board in a centrifuge and turn the damn thing on and spin the crap out of it? That would probably squeeze out a ton of epoxy hahaha.

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Too stiff and heavy

Too stiff and heavy