splitting a homemade blank

hey guys i made a couple home made blanks a few months ago and now that one of them is fully shaped I need to split it straight down the middle so i can glue in a stringer. does anyone have any easy methods to do this so that i can ensure that the cut isn’t at an angle? i would make a hotwire, but i’m on an already low budget and im about to order epoxy and fiberglass. does anyone have any experience from this? thanks a bunch, cam

Hello Novasurfer ,

I’ve never split a shaped blank…you might want to explore other options…

We’ve screwed up quite a few EPS boards down here in San Diego here’s a few tips…

Jig saws work good , make sure the blade cuts square.

Hand saws work good too

Circular saws (skill saw) are a bad idea. The saw cuts so fast the EPS melts and that gets on the blade and binds up everything. We had a very close call over here. Don’t do it.

We tried to use a 12 inch hot wire like a saw but that idea needs more work or a better jig or something

After cutting the foam spend some time sanding the cut edge. We like to use a masonite template to get everything square.

You also need to make sure your stringer material is good. If you are using wood have someone run it through a planer. After all that work we glued up a couple of boards and the wood stringer was not an even thickness. Air brush time…

homemade = eps?

depending on your foam and glassing schedule, stringers are not necessary.

if your foam is the lightweight variety and your using very light glassing, stringers help, if the stringer is thick.

#2 eps with 66 deck and 6 (or 44) bottom plus foot patches will do fine stringerless.

many people are doing stringerless boards…

stringers are primarily there to keep the blank ridgid while shaping.

fiberglass is the board’s strength.

i know for a fact key people in the know are doing #2 eps stringerless with 666 deck and 66 bottom for their heavy waves travel boards…about as unbreakable as modern lightweight surfboards get.

The blank is made from 4- 1" sheets of foam insulation and i dont know what weight it is but i know just from holding the board that it isnt verystrong so im going to put in a stringer. how can i tell what weight the eps is?

hate to break the news…

the 1" insulation foam available at places like home depot and lowes blows.

that stuff is like 0.5-0.75 lb density

if you gently squeeze it with your fingers it feels soft and spongy

the 2" foam is denser and is better but still not adequate for most apps

most surfboard foam feels somewhat firm to very firm

with the stuff youre using youll need to go compsand or a shitload of glass (heavy and expensive)

otherwise youre wasting your time

just fair warning you

yeah thats the stuff… alright thanks… i just wasted a shitload of time… but i need to get legit blanks now… thanks for the info man… -cam


i just wasted a shitload of time…

No you didn’t, it was good shaping practice. Don’t you think your second

board will come out better than the first?

you’re right… thanks mike. it was just kind of at that moment i felt like that and i did until i read what you said… i cant wait to shape the next one…

if your using homemade eps blanks i find its best to shape the stringer and glue it into your

blank before you shape your board thatway your guaranteed to get the right foil and you dont

have to mess with the stringer later

how did you glass them?

Hello novasurfer ,

There’s no reason why you can’t add a stinger to your board. Careful measurements and some planning will do the trick. There’s a thread by Deanbo asking how to pull this off. As a smart ass I told him to use a pencil and a ruler. Guess what…The Swaylocks gurus came through and I recommend searching for that thread or contacting Deanbo for a link.

I was also thinking about using 2 inch fiberglass strips down the middle of the board under the glass instead of a stringer.



Hello Nova…

You’ve asked plenty of questions. Here’s a link to one of your own posts. Time to glue in that stringer and glass the board.

Post some photos for Chipfish61

i definitely will… ben has helped me a lot with all of this stuff… thanks for the info. haha i completely forgot about that thread… it has been so long since i started this board (almost a year)… thanks, nova

Hey Nova, I would give serious consideration to the balsa skin idea. I’ve just glued in two ply-wood stringers into an plan shaped eps blank. They suck, so I’m scrapping it in favour of a non stringered blank with balsa skins (when I can get some balsa).

What kind of glue are you using to laminate your sheets of ply? Isn’t there anything you could use which would add some stiffness.

Good luck!

Hey Nova - I do like Ham… I see the stringer as the spine of my board, rocker and foil done. I helps to buy to blocks of foam then the factory straight edge is built in. No matter what, you can make that board work, don’t give up.

yea taylor factory blocks are the job with straight edges to glue to the stringer

nova remember you dont HAVE to put in a stringer.i made a 7’ mini mal with no stringer

glassed with 6oz glass and epoxy and its holding up perfect,no compresson dings or anything

imo an extra layer of glass on the board eg.3x6oz on the top and 2x6oz on the bottom

would add less weight and more strength than a stringer

and post pics when your done,i love seeing other backyarders creations

alright guys… now you have gotten me excited about this board again!

fatbaslard- now that you say it i think it would be sweet to balsa skin this board! but i just cut the board in half the other day with a hand saw… should i glue in the stringer like i had planned or should i glue the two halves back together and then balsa skin it? also, how do you do a balsa skin and what kind of balsa(measurements) do i need to get?

hamnsalad- like i said to fatbaslard, i just cut it in half this past weekend…oops. what should i do? glue it back together or put in something to act as a stringer and then balsa skin it?

anyways, i want to thank you guys for all of your encouragement and help… i was pretty bummed after i heard that the foam wasnt the greatest for boards but now im excited to continue and finish this board!

Hey Nova

never skinned a blank with balsa before so I’m gonna be making it up as I go along, so far I have asceratined that the best way is to vacuum bag the skins on with a layer of glass between the foam and the balsa. I’m gonna think of a less complicated way if I can.

As for the board in two pieces, well, seing as you’ve chopped it you may as well glue a stringer in there. If you’ve already pretty much finished shaping it as you said, use one half on edge as a template to mark out your stringer then cut it as accurately as you can, then glue it in with gorilla glue or something else that expands. Best way to clamp it together will be to wrap a bunch of luggage straps around it (the sort you use to stop your board flying off the roof of the car) with some wood battens strategically placed to keep the two halves aligned. Watch how tight you pull the straps or put something in there to stop them compressing the foam.

What to use for the stringer, now there’s a debate.

Anyone who wants to contradict this advice and tell me I know nothing, well your probably right!!


Chipper, come home!

Hey Nova,

How on earth did you get a straight edge/cut with a hand saw? I did something similar with my first board. I glued 2 sheets of foam together, cut it in half with a hand saw, glued in my stringer and shaped. My hand cut was so not straight! Even after much sanding and trying to get straight edges there were quite large gaps on either side of the stringer. Unless you have a nice straight edge, I’d just say glue the blank back together cause it will be a headache otherwise.

i have a chalk line so i just followed that line exactly and stayed at a 90 degree angle…