Looks cool. What’s the strip of cloth for?
What’s the principal foam.
Are you finding quantities of gorilla pu glue larger than a few oz? Where?
You using any carbon cloth on the bottom?
At my level of board making, thats just more bells and whistles…corecell and carbon fiber on the same board,i might as well just buy a nice blank with that money. Plus my shapes are a crapshoot…carbon fiber on a dog is just lipstick on a pig. I already tried to build a space shuttle but it was more failure than it was worth!
Howzit?
Built a couple XPS boards…
and from my experience XPS seems to have a temperature range… as long as you stay under the temp it was glassed at and follow SD’s guidelines… no problems here. 60 grit and let it sit in a sunroom for a day or two… make sure to clean it really well, and don’t pull the squeegey too hard. drop the temps as is starting to kick… I went from about 80 down to 60’s by crackin a window.
as someone says, don’t bend rocker into it unless you use thin sheets. it’ll just snap.
that 1pound EPS from home depot just seems to chincy to waste a glassjob on it for a ghetto build style… atleast with XPS you get good twang and feeling.
Before glassing my first board I did some tests… I’d say on 40 or 60 grit scuffed XPS foam the adhesion is as good as PU foam with PE resin for strenth if you try to peel it off a test panel
the tiny sheared cells fill with resin and do a great job of bonding.
is it for production? nope. but for sub 100$ experiemental shapes its the way to go. EPS feels terrible after.
STYROFOAM™ Brand Extruded Polystyrene (XPS) Foam was invented by Dow
more than 60 years ago. Recognized by its trademark BLUE™ color,
STYROFOAM™ Brand XPS Foam Insulation features a closed-cell structure, high R-value of 5.0 per inch and the highest moisture resistance of any foam plastic insulation. It provides long-lasting thermal performance in roof, wall and below-grade applications.
threads like this is why i love sways… “this won’t work” all the way to “i love this stuff”
i’m a fan, and have had no problems other than some gassing along the stringer of my 1st build. Here in the UK is never gets really hot, but inside my old black van it certainly did. I left boards in there for a week while I was traveling and had no issues.
My personal feeling - as I am not going to make anymore sweeping claims here - is the brand or specific original application of the XPS used makes a big difference. I remember all the blue foam builds on here and the woes of those folks, but that drewtang guy in florida makes them with no issues these days. I never tried it as I can’t find it over here. But, I’d bet it probably evolved a little since their 1st recipe, or the resins used have.
I’ll build more personal boards out of the stuff, and abuse them. For experiments, it just makes financial sense to me. The benefits of strength and weight reduction, as well as longevity are a bonus.
blah blah ablah… some like it, some don’t. variety is the spice of life!
Bending it is fine if you use the right thicknesses. (I use 2x 20mm (never go thicker than that if bending), a 15mm and a 10mm in high density Dow foam) - you need to use a rocker jig and glue the blank in shape then shape it. Like glueing up a skate board deck. The flex you get out of the different thicknesses is amazing!
Your way sounds interesting, I hope it works…but it may cause deformations in your skin of your board and xps has memory.
So, without bending it, how are you putting rocker in the board?
Almost done fabbing a blank out of the pink stuff. After shaping, I was just going to glass and weight it down while it cures to lock in the curves. Sounds like that may be an error.
I think XPS has it’s place in surfboard building. Gary Young has been using it for ages. The HD 100-60 psi foam shapes different than the 1.5 LB xps.
I have had no problems with it as a core in foggy San Francisco.
Yip I agree, when I have done perimeter type railed boards I figured if I was going to glue something round the outside for shaping rails it might as well be higher density and hydrophobic, so it works there, we will see if it delams or not with dings etc…
Nocean, i do it two times. On both i have dings, so much people in water here !, small delams around ding but nothing bad and no need of fast repair. I think XPS on rails is a good thing but it’s hard to shape well (like i want) for me so i go full EPS with good epoxy seal.
The HD 100-60 psi foam shapes different than the 1.5 LB xps.
Lavarat that is the same thing I have found.
XPS is a mixed bag.
Some on here are glueing sheets together and bending the rocker into the blank.
Different densities are being use.
Various Manufactures.
I make rocker profiles and hotwire the blank without stressing the blank.
A glue line along the rail does not make logical sense to me unless I'm missing something? (Reference to gluing thin sheets together)
I find that the XPS I use (DOW SURF CORE) is actually easy to shape (Much easier than EPS) so I don't get it?
Every seems to have a different view point in regards to XPS maybe that's why were still talking about it?
Kind regards and Happy Board Building,
Surfding
[quote="$1"]
The HD 100-60 psi foam shapes different than the 1.5 LB xps.
[/quote]
I bought blue Dow sheets from Lowes here in San Diego for my project. Each sheet was 1"x24"x8', and cost just under $10. I cut a scap piece into a little cube, weighed it, and found that it was about 2.5 pounds per cubic foot. It seemed to shape nicely with my modified Hitachi planer. I did notice some tear-out if I cut too deeply or too fast. It wasn't a problem though. Normal cuts came out nice and clean.
[quote="$1"]
I make rocker profiles and hotwire the blank without stressing the blank.
A glue line along the rail does not make logical sense to me unless I'm missing something? (Reference to gluing thin sheets together)
I find that the XPS I use (DOW SURF CORE) is actually easy to shape (Much easier than EPS) so I don't get it?
Every seems to have a different view point in regards to XPS maybe that's why were still talking about it?
[/quote]
Where do you get the thicker sheets of Dow Surf Core foam? I hate having to glue sheets together.
I have 11 billets. Had over 300 four years ago. PM me with you want a billet.
Instead of making a new tread I thought I would just post the progression of a ordinary simple build using DOW XPS HPSB.
Printed rocker Template sprayed to a piece of masonite: This is used for a hotwire guide to eliminate the excess foam. Notice I use whole billets as to not stress the blank. Gluing sheets that are stressed into the rocker profile is failure in the making. Plus having a glue line in your APEX is not a good Ideal.
Notice the computer paper used with the printer in banner mode. LEXMARK Printers with a Banner Feature in the driver software is the key. The Dot Matrix printers use to work in Banner Mode with DOS however I have not found a driver to work in Windows in Banner Mode. If anyone knows were to obtain a banner driver in windows for a Panasonic Dot Matrix let me know because I have one that is brand new I bought 6 years ago that has never been used. I have bought two Ink Jet Printers from Lexmark since.
Here’s some photos:
I will finish this when I get back from my holiday.
Kind regards,
Surfding
COOL! i'm looking forward to this... have fun on your trip
If it’s Dow High Load Blue, it should have a 40 or 60 printed on it somewhere.
What are you gluing your XPS sheets together with.
I never glue sheets together. The billets I have are 5" thick 24" wide and 8’ long.
Stringerless and the strength comes from the glass schedule. Vacuumed with a rocker table.
To be expected if you have billets.
I was thinking of gluing my Dow HL 60 (2") on top of my Dow HL 40 (3") with some kind of urethane glue. Will be adding a new twist that should improve blank strength significantly, including a floating balsa stringerin the mid-section.
If you have to use thin sheets Polyurethane Glue is easier to shape than other glues. Gorrilla Glue maybe your best bet.