Shaped a blank with a PVC stringer today for the first time. I’ll glass it tomorrow. US Blanks Orange Foam. We’ll see how this board holds up over time. Real springy and a little more difficult to shape. Probably go a little heavier with the glass job than I would normally.
how long, how thick?
I’ve made a few. They are heavier and have way more flex. I was using wider laps to counteract the flex.
My little rant…
It always frustrates me when a good company cheapens a product to make a few pennies. Go to the hardware store, and pick up a piece of PVC pipe and bend it. Now pick up a broom handle of the same size and try to bend it.
There’s your answer on flex. Now that broom handle costs $10.00 while the PVC pipe costs $2.00. There’s your answer on cost.
As for the Orange foam, I really like it.
Pvc use for stringer is extruded, it’s half lighter than one’s use for pipe. This material has a low stiffness but as all low stiffness polymer (pet, pp, pa(nylon),etc…) It has a good thoughness because of it’s elongation to break. So your blank is flexier than a wood stringered one’s, it’s need less forces to break but more energy. Is it a good thing?..
Hi Mako, are you going to tension or block up the board while glassing to make/keep your intended rocker? -J
PVC stringers are good in EPS Epoxy boards, I don’t know about poly.
In EPS the load spring and recovery is fantastic. As I have mentioned before it will take years off of your surfing. And if shaped into a good board…it will allow you to go places on a wave you have only dreamed about.
The love comes from the PVC increased ability to bend…combined with the epoxys increased ability to flex, combine this with to open pores of the EPS for bond strength and you get a flexible…sling shot recovery out of your bottom turns and cut backs.
Poly and wood wont due this. I have had some failure with EPS and PVC stringers…but those boards would have broken under any other build construction too…so I can’t fault the material
Good high performance boards are not meant to last a life time. if you want durability then you should wrap it in 3x6oz and call it a plank. Some of my PVC with with 6/4 tops boards are still out there and it’s been 5 or 6 years of being ridden hard and put to bed wet…That pretty good in my opinion.
I think a poly blank with a PVC stringer covered in poly resin will break due to the inability to flex…also wont the PVC melt with resin smeared over it?
PVC is compatible with poly resin.
I glassed it and hotcoated it today. This board is 5’7 x 18 3/4 x 2 3/16. I went with a 4oz bottom. 6+4 Deck with the 6oz wrapping the laps about 1.5" Small stomp pad. Really took my time to get the lam job perfect. Board came out very light. I’ve got to say I really like the look of the white stringer with black glue.
Another thought on this blank: It’s a good thing I modofied my Hitachi planer because I would have really struggled to shape it with my Skil 100. The lightwheight planer was a big advantage on such a flexible blank.
I cannot stand pvc stringers. I think they degrade a board’s flex by making it highly variable, its bond to the foam, and its lifetime. After I broke three of Greg Loehr’s pvc stringer boards in a row and fixed one that buckled three times, I gave up. It will not give under foot compression, so you’ll get cracks on the pvc stringer on the deck. Cut a plastic stringer and hold it. It wobbles all over the place laterally. Lateral stiffness? Uh, nope. You’re counting on just the foam core and glass distributed over the volume. Bonding tightly closed cell plastic to eps, meh. scuff the crud out of the plastic and then either put on a bonding agent that either melts the plastic to the foam and doesn’t melt the foam or hopefully gets a good enough bond. Wood is far superior in my mind. Haven’t looked back from that experience. Coming from someone who tends to use CF on the rail as a flex agent, so you know I live dangerously. Rant over.
Extruded pvc = pipe = high density, low flex
Expanded pvc = foam = low density, high flex
I’ve been using expanded pvc as stringer on eps boards for a long time with very good feedbacks. Easy to shape and very good flex.
This would be a great place to start a discussion on how much flex is best and how to get the right amount of flex. Sways has never discussed that…(yes I’m being a troll)
I like a slightly flexible nose, really stiff middle area, and just a little flex behind the front fins. I do mine with changing the number of layers of carbon. One layer in the nose, three layers from midpoint to the last foot, and two layers in the last foot.
For me the best is the stiffer board you can use that not chatter in bumpy waves. It’s more the quickness of flex return than overall flex max number. To much flex slow boards. Pvc stringer can work good in eps epoxy board because it increase “plastic flex dynamic” =slower return to original shape after flex=less chatter in bumpy waves.
Wrapped this project up today.
Detais?
This board is 5’7 x 18 3/4 x 2 3/16. I went with a 4oz bottom. 6+4 Deck with the 6oz wrapping the laps about 1.5" Small 4oz stomp pad. Board came out very nice. Really like the look of the black glue up with the white stringer. Rider is a stoked 5’6 130 pound 15 year old. (My oldest grom)
Cry and complain all you want…I’ve worked with PVC stringers 1/8 inch thick, 1/4 inch thich, 3/8 thick… so…make sure when you go on a rant and cry and complain… you tell the world how thick the stringer is and what glue you used. Glassing schedule matters too. Foam denisity…type of foam ect…and tell us how awesome you surf…post photos too
For a backyard guy cutting his own EPS blanks with a hot wire…PVC foam stringers are a very good option…I’m not making many backyard blanks at this point but the PVC foam has worked just fine for me.
Correct! Ever rode a plastic bic board? I rode one recently, it’s flexy and slow!
WTF!!!