Well after numours attemps at buying a blank i just cant chose one because there is so many style of boards to shape so iv decided im going to try n shape my first. hoping to shape it around 5'4 x 19 1/2 x 2 3/8 with a five fin set up so it can be riddin eather quad or thruster. i want to go for a round tail style sort of high performance fish style while still having a bit of a low type rocker for speed and a double concave though out the centre. now i plan on just going a basic pu blank from oceanfoam and the closest size blank they have to what i want is
6'6 x 24 1/4 x 3 3/8 now i know theres heaps of room to shape the board but the one thing im not sure about is the rocker, i emailed them a while back about the style rockers they offer and they came back with HP ,STD and oldschool now im thinking of going hp but im not sure yet because i want the board to be fast but also have that high performance feel. the reason i posted this was i wanted to know if anyone has been in the same situation because thats about 14inches iv got to take off the board. so should i just go the hp and work out how much rocker i want towards the nose and tail by measureing it out or do i go somthing that is a bit smaller and not as much to take off? thanks for any help with this.
It somewhat depends on what your definition of a fish is. I notice your blank source is in AUS. The term “fish” sometimes means something a little different to surfers from the U.S. vs outside of the U.S… Here in the San Diego area, which is arguably the birthplace of the fish, that term refers to a short, wide flat board with the wide point forward and a 16+" wide tail with a 5" buttcrack and an 11+" width from tip-to-tip across that buttcrack. Elsewhere, the term “fish” often gets applied to any board with a swallow tail, regardless of how narrow and rockered they are.
I don’t know anything about Oceanfoam’s blanks so I just went on their website. Although the blank you’re looking at is the only one they’ve classed as a kneeboard or fish blank I think it’s way too big for what you’re trying to do. With the dimensions you have in mind you’re looking at having to take 1" of foam off the thickness. That’s a lot of planer work, and I do mean a lot. Besides that, taking 14 inches of length off means flattening most of the rocker out of a fish blank. I like really flat rockers on fishes but even I wouldn’t drop to 2" in the nose. On most polyurethane blanks taking that much thickness off will also put you into softer foam, which will lead to more pressure dings than if you were only taking off a little.
It’s true that you can cut the rocker back into the blank with a planer but that requires quite a bit of skill and experience to get it right when you’re talking about adding 1" or more rocker at either end.
IF their shortboard blanks really are wide enough to yield a 21" maximum width on a shortboard shape you can probably squeeze a 19.5" width on a traditional San Diego-style fish shape, with the wide point forward of center. If your wide point is at or behind center then it’s a guarantee. I don’t know what your other widths are but I’ll bet they’ll fit on most of those blanks, too. Without altering a “standard” rocker on the average shortboard blank, taking 4" off of either end will get you somehwere around 3.25+" in the nose and about 1.5" in the tail of a 6’0" shortboard blank that naturally has 5" in the nose and 2+" in the tail at full length. If you wanted more rocker than that you can either go with a slightly longer blank or just add it in to the natural rocker of the blank after you cut the template out.
A professional shaper would also be considering where on the blank the nose and tail rockers start to curve in relation to what they want for their board, but that may be a bit much for you to to bite off at this point. For now, you want to identify how much rocker you’re looking for at each end of your board. Just knowing that will make it easier for you to pick a blank.
cheers Gdaddy really appreaciate the time you put into the post, it did help out heaps i think il just start off by shaping a board simlar to my standed shortboard for now. cheers mate