another eps question

i have a heap of these eps blocks (40mm x 40mm x 200mm long) we have been using as void formers in a concrete slab left over.

i was thinking that i could glue them together in a brick pattern to make sure there is no plane of weakness and then laminate 2 sheets together to get the thickness.

people have mentioned 5 min epoxy to glue together, is that araldite in oz?

would the large amount of glued joints act as a stringer?

cheers

boothy

A neighbor of mine had success with that scenario, there is a thread if ya search, cant remember the name of the thread though.

http://www.swaylocks.com/forum/gforum.cgi?post=398182;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;guest=21121815

yeah i have been following those threads i guess my question was more along the lines of due to me having blocks, 200mm long each not sheets, there would need to be alot of glue holding them all together and then would that grid of glue act in the same way as a timber stringer?

cheers

boothy

Boothy,

Araldite glue sounds like epoxy glue. Epoxy alone is not strong. Ever had those drips of epoxy hanging off your board? They break easily.

If you would use fibre glass at the same time, then you increase the success rate in my opinion.

Why not go with epoxy and fibre glass as a stringer? You can easily give it a colour too. You would need a lot of regular 4oz glass to build up a 1/8" thickness though. Better use 40oz, if that exists…

Better answer?

Wouter

I use white glue, like the stuff kids in elementary school have to glue up EPS pieces to make board blanks. It is soft enough to sand through without causing tears or high spots in the foam. That’s important if you glue up several chunks of foam and then have to cut into the glued up section. Epoxy can make a very hard to cut through bond. I don’t know about using pieces so small, because I think the amount of glue you’ll need may add a lot of weight.

I don’t use stringers, but I make compsand type boards, so they have a fiberglass/wood/fiberglass shell around the foam.

I’ve only made one EPS board without the wood skin, it is 2 lb foam and has a 1/2" redwood stringer.

Someone posted a thread here that talks about no stringer EPS boards. He does large laps on his lams, and the laps increase the boards strength. I don’t remember if he adds a rail band.

Interesting project. Couple of things. Shark Country is right about high spots when you sand over glue lines. Sounds like you will have a lot of them. All in all I’d go with white glue, but you might consider the white foaming PU glue. I’ve had some trouble glueing up stringers with white glue and having not set up for lack of air.

Keep it a shortie and skip the stringer.

A bigger question is what weight and type the EPS foam is. I’ve seen some flimsey foam in packing. Find someone who knows foam who can give you an idea about the density because it will be important when you glass it. If it is the light .5 pound stuf, forget it. I guess you could weigh some known volume chunks and calculate the density.

Just know that what you are doing is a one off fun project and not worthy of sinking a lot of money in. Do it and have fun and you could end up with a servicable board for a while. Love to see some pics when you are done and learn how you solved some of the problems you will face.

thanks all, yeah i guess i will have to try it and see.

i was going to shape a short board anyway, so i might as well start glueing. its gonna take a while…

i will take some photos and put a thread together, i have read many fantastic stories on this site, maybe its time i tried to put something up.

cheers

boothy

When you glue it up, try putting the glue in the center of the blocks and not all the way to the edge. That will save some time, glue and weight. When you start shaping it less glue will be an advantage. If you have gaps where the blocks meet, you can always fill them with a thin coat of spackle. Lots of guys seal eps with spackle before glassing.

Some will lay on a thin coat of epoxy mixed with filler. If you do the epoxy coat be sure to make it as smooth as you can. Sanding that later is a real hassle.

Stringerless with a nice wide wrap around the rails when you glass should make a strong shortboard.

I Reckon you’ll probably end up spending more on glue than the cost of three EPS blanks.

Unless you’re getting the glue for nothing.

With epoxy glue lines they always seem to sit a little bit higher and when you take them down there is a good chance you’ll rip the beads out next to the line having to fill with more epoxy and adding more weight and time to the project. Then you have to bend the rocker in.

Profiled eps blanks cost me around about $25AU each, 1 bottle of vise foaming poly glue cost $13 for 500ml.

Not trying to put a downer on your project Boothy just throwing up some ideas for ya.

Good Luck

Daren