Hi all- Can anyone explain the beat way to cut poly blanks in half ? Do i need a special jig or apparatus? Cheers petey
A straight edge, clamps, and skilsaw is all you need if the purpose is to cut lengthwise for adding a stringer or the like.
thanks Sammy makes sense . any type of appartus needed to keep blank in place?
Yeah, an extra pair of hands.
I use a big bandsaw…
I want to cut a blank in half that already has a stringer in it…
It’s an EPS blank…
Do you guys think I could cut along the stringer with a handsaw using the stringer as a guide?
I think I’m gonna give it a try. I wanna add a different stringer.
The short answer is yes. Use a fine toothed crosscut saw, using long shallow angle strokes, along the side of the stringer. After about 2 feet in, tape the blank at the cut end together, and complete the cut. Makes everything more stable.
Unless you have a whole lot of experience using a hand saw the chances of getting a straight line, using only the stringer as a guide, are pretty slim. I’d say you’ll still need to use a straight edge to guide the saw. Plus, a hand saw will be more difficult to control in the vertical axis of the cut.
I did the hand saw route once and found that the glue had move out into the foam and diverted the saw blade away from a smooth cut along the stringer. You will need to move over about 1/4 inch each side.
All the best
Why are you cutting it in half??? I am an eps devotee but have never had any problems cutting PU blanks. GO FOT IT!!!
Yeah handsaw is tricky to keep the cut 100% level or plumb because of glue … tried that before best to do it by bandsaw/skillsaw and cut either side away from stringer a bit… For halving a stringerless i have found a flexy aluminium straight edge say 80mm by 4mm thick quick clamped to the blank works well with a skillsaw slow and steady… Make a cradle to hold the blank from “squeezing” the blade on the last couple of inches of the cut make sure that the blank falls apart as opposed to folding inwards jamming the saw or like mentioned above extra pair of hands…
hmmm thanks for the info guys.
I’m gonna try it one way or the other.
Don’t let them fool ya!
Band saw? Baloney!
Unless you are cutting center for stringer.
SammyA “A straight edge, clamps, and skilsaw is all you need if the purpose is to cut lengthwise for adding a stringer or the like”.
BT “Use a fine toothed crosscut saw”
Basically get your lines down (nice to have stringer as center).
Sorry, I would recommend the **skilsaw **if you lack the skill.
However, be aware you will have to go to the handsaw unless you are using a beam saw.
I find that starting perpendicular and angling way down the line, using long cuts on my line “slow long strokes” staying square on the line, smooth no choppy crap.
G, I hope this helps…
Go with the hand saw!
Eh that’s how we learn.
I have done it, just as you described, on a poly blank. Took a handsaw, used the existing stringer as my guide, and cut away. Little on top, flipped it, little on the bottom, back and forth like that. Worked fine for my less than stringent standards! I added a wider stringer, and glued it back together. Didn’t even worry about the little bit of wood left on each half from the original stringer. I use a handsaw (sometimes) in my day job, so maybe that’s why it was easy for me?
If I had a bandsaw, I would have used it, why not?
I have a skilsaw and a beam saw, which I also am very comfortable with, but in this case I didn’t feel it was the right tool to attack a helpless little surfboard blank with! The handsaw seemed more humane, haha! Anyway, I just dove in and did it and everything worked out fine.
Im thinking (for poly blanks ) to change saw blade and use a masonary blade cuts clean and smooth with less chance of ripping small chunks away from the blank. Do not try this on poly blanks because surely it will melt the foam!
there is nothing baloney about using a band saw, Matt. Oh and by the way, you’ll get better glue lines if you put half your clamps on the bottom of the board, facing up, instead of all of them on the top, facing down…
Skilsaw is a great start but if the blank is more than 2&1/2 inches thick, the blade will not cut all the way through. You can then finish off with a hand saw. Any circular saw will do. Use a cheap finish blade with close set teeth. About seven or eight bicks for the blade. Make sure the bottom is flat and true before sawing.
Any old skills as blade is fine a decent quality saw will make a better cut as above bottom needs to be flat and curt from the bottom of the board it needs to be supported so it doesn’t flop around halfway through.
A 8 1/4 will cut 3 in deep and imo cuts straighter than the little saws.
Mean no step on honorable toes.
Many just don’t have band saws.
Including me, so I eat baloney to save up, eh.
BIG Mahalo on the clamps!
Pretty much on my own doing things and learning.
Seemed logical for HF POS’
1st better clamps.
2nd an extra set of hands.
Edit in the end the “Rasta” didn’t come out all that awful.
Aloha Nui Loa
All of the above methods will work fine if done accurately… the bottom line is ending up with two accurate flat surfaces , to laminate together… be prepared to true up the faces with a jointer , if any mishaps occur . I prefer to get my PU blanks pre-cut at the manufacturers whenever possible , because they are very good at it …if I use a blank that’s been centre cut , for a multi-stringer glue up , I use my bandsaw , with a 6" height extension on the fence , to cut my outer stringers , keeping it firmly on the fence , so the cut remains vertical…PU blanks rarely have a dead flat bottom , so it’s important that the cuts are kept straight and vertical , and all in the same plain.