EPS 1.5lb finished weight

I’m getting ready to glass a board using 1.5# EPS foam, sealed with drywall sparkle.  The board is 5’8" X 20" X 2 3/4".  I’ll be using using a sing 6oz on the bottom and 6+6oz on the deck, 1/8" wooden stringer.  Can anyone give me a guess on the finished weight?  Thank you 

Six lbs.

Sparkle, LOL!

Lowel, are you sure? Haha, Looks like you are.

Allright, allright, allright!

L-Go forth and glass your surfboard! Let us know the final weight.

eps, 1.5PCF, 32l, 1.13 CF     1.7    pounds

stringer, 276.1 sqin x .125" pine/bass/poplar, 5.3 oz,     0.35    pounds

sparkle, unknown        ? pounds

glass+resin, 3 layers .004"FR4 , 1347.493 in^2 each,5.76oz each,    1.08    pounds

hot coat per greenlight chart 8oz/side,     1    pound

gloss coat, same as above    1    pound

3 fin boxes , Futures thrusters, boxes only, 2.5oz,    0.16    pounds

    =5.29   pounds +/- sparkle, sanding, leash plug, wax, etc…

 

I intentionally erred on the heavy side and according to your calculations came out pretty close.  Fins are not usually calculated into the weight of a finished surfboard.  Unless glassed on.

Yeah, I’d second Mcding’s call.  We don’t know how many fin boxes are going in, but that can add up as well.   Just a hunch, but  I doubt the OP is using Futures.

Sparkle: the ? evil.  Help me fill in the blank.  “Gleaming”?  What would you put in?

Don’t know if you are a novice at glassing, but a novice is usually not that good at pulling excess resin off the blank.  Extra resin is extra weight.  If you did a really good glass job and used Fusion light weight plugs(Thruster-3 plugs). You could get the weight down to the low 5.  Otherwise I bet on six.  If you want light weight; glass it with 4 oz…  You could get down under five lbs.most likely.

Some of you may remember a thread done by surfding a few years back in which he did two boards.  One 1.5 EPS and one an Arctic Orange Polyurethane.  Seems to me they were down in the four lb. range with 4 oz or so difference.  Might be cool to dig that one up out of the Archives.  My ideas on weight are “ass talk” anyway.  I never weigh anything.  I pick up the finished board under my arm to see how it feels.  Then I comment;  “Oh, That one came out nice and light”.  Lowel

Yes to all of the above.  

I think at one point the people who were doing them decided that weights under 4.5# didn’t feel that great under foot.  

Yes.  I’m too old and fat to know for sure, but I would think that there is a limit to;  “How light?”

Interesting discussion though, provoked by a basic and simple question…  Going to do a little digging and see if I can find Surfding’s original post and experiment.  Miss that guy.  Too bad his skin was thin and his ego fragile.  He always contributed some great stuff and was a real inside the industry guy.  Lowel

i do all my boards with 1.5 lb now. most of time for smaller ones, carbon U stringer, 2x4 oz bottom, 9oz stitch glass + 4oz top, epoxy micro spackle on blank. At that size a fish weight around 2.8kg and will be what some say bulletproof. In general guys that ask me board want “bulletproof board” at same weight than their standard PU/PE but not too stiff, that’s what i do.

Some sell full 4oz on light eps board with a piece of thin carbon, ultralight shit !

Yes I bet with the stitch 9 and 4 deck never any dents.  1.5 and the Carbon stringer keep the weight down, but you gain some of that back with your lamination.  Have you got a pic of just one of your clear boards?  I know you have posted pics before, but I don’t remember a clear.  Would like to see a visual of your layup, stringer etc. you do a great board and we should all be straining toward “bulletproof”.   But if everybody built them that way there would be no Surf Industry.  Surfboards would be like Dodge trucks in the 70’s and 80’s;  you’d get bored with the way they look, before they ever wore out.

One of the clearest deck i do late. You can see stringer in the core connected to deck skin. With this glass schedule deck moderately foot prints but not usual egg dent. 1.5 lb have some elasticity so skin don’t feel hard under feet like sandwich builds.

Looks great!  Still pretty light I bet for something that is built to be “bulletproof”.  I don’t know anything about stitch 9 other than when I have seen you refer to it in your other posts previously.  I’m gonna do a google and see what I can learn .  What would be the best name or tech term to search under?  Again,  I really respect what you do with your boards.  They always look fantastic.  Good shaping and really on the cutting edge construction wise.

Thanks. 9oz stitch glass is the lighter standard for many composit industrie. not clear sizing so better with color resin. Cheaper than lighter clear multiaxial glass sell now for surfboards. Can be lam tight. U carbon springer is made with 2x9oz UD so a bit stronger than super thin strips LOL