This is my first post but I have been reading swaylocks for a few years now and the info on the site is amazing. I have made a few surfboards out of dow blueboard and I have always added a stringer to them, they were all shorter boards tho. I searched the discussions for anyone that has made a longboard without a stringer but have had no luck.
So I was wondering if I could make a 10' longboard without a stringer? Would I have any problems with strength, or would there be too much flex? I am going to glass it with two layers of 6oz on the deck and one layer on the bottom. Any suggestions?
Stringerless. Top to bottom: 6 oz glass - bamboo veneer - 6 oz glass - eps foam - bamboo veneer - 6 oz glass, carbon rails. Seems very solid. I don’t ride a longboard often so I wouldn’t be able to compare flex characteristics but the board seems to work quite well.
Max, Yes you can make a stringerless longboard but depending on how much you weigh, you will encounter all kinds of problems especially breakage, much less too much flex. Think about it, you are putting a hard shell on a soft flexy substrate. Even in the old days when boards were glassed with 10 oz. they still broke although not too often . If you are set on no stringer at least try a denser foam at the rails for some rigidity.
My friend has made quite a few at first with Warvel P/U rails, and lately with all eps (US Blanks or Marko), bamboo skins, and carbon over the rails. The present construction is the only thing that will last under his team rider. Here are some links to pics of the boards in action.
Thanks, those are some nice pics. I think I’m still undecided but it seems I could try it and see what happens. Where I surf, in eastern canada the surf doesn’t get huge often, when it does its good but most of the time its mushy so I’m looking to make a longboard for those days, which is most of the time…
Max, the key is how thick the board is. Break strength increases exponentially with thickness. 6X6 and 6 is not enough. I would at least put a 2/3 deck patch and an extra layer of 4 oz on the bottom.
I have shaped 4 stringerless 9’2"s, Bing Lightweight templates with updates. Double six with 4’ patch, single six bottom, tail patch. Haven’t broke one yet, used only in 6’ and under surf. Super flexy, faster than stringered and much smoother riding.
Look up the thread where I did stagger lapping on a thin EPS stringerless stinger longboard. Just stick stagger lapping in the Sway's browser, it will probably pop up.
Also look up ASTM info for span, load bearing and break strength as building codes demand in use of joists.
Whereas the greatest deterrent to avoid breakage is thickness (in any material), the ability to "manage energy" (aka absorb, rebound, deflect) and recover is of paramount import here.
This translates (at least for me) into thicker perimeter reinforced stringerless vehicle.
If your a vac bag guy, then the lightweight core and skins with reinforcing of conventional or exotic materials between the skins creates a 'stringer effect' w/o a conventional stringer (I Beam).
Everything breaks given a load is experienced at failure point for the application chosen.
Just remember, the longer the fulcrum, the higher the chance of failure in the application we use surfboards in.
Along with thickness and lapped rails, consider shaping slots in the rails. The added contours will help resist flex and breakage. An example of what I'm talking about is this board by Ricky Carroll. It obviously has stringers but you can see the slots...
