Managing volume for midlength surfed in larger waves

I’ve surfed larger waves on shortboards and longboards. With shortboards I duckdive. With longboards I turtle. Easy.

Now I’m shaping myself a midlength and was wondering how volume should factor into it. I’m 155lbs and when my boards get to around 30 litres I start noticing the extra effort they take to duckdive. With a 7’ retro-ish shape I’m probably easily past 40 litres. Do I try to get the volume down? I’m thinking even 40 litres would be be a chore to duckdive. Below that I’d be worried about defeating the purpose of the concept as well as introducing a higher potential of breakage. Or should I go with what feels right and just plan on turtling when the waves get bigger?

You can sorta duckdive a midlength, just get the nose under and hang on. Or turtle. But you can’t duckdive like a shortboard. If the wave is big and you are near the impact prob best to swim down and use the leash. I don’t hear it mentioned much but when I was younger & surfing bigger deep water waves I would try to swim down deep enough and hard enough to pull my board down below the surface.

40L isn’t that much volume.  I can do (and have done ) 40L in a 5-4 fish or Biscuit type shape.  

40L in a midlength shape isn’t hard to duckdive if you have some technique.   It takes more than just using your upper body strength to push the nose down, though.    Pushing the nose down and allowing the tail to float under the theory that the wave will “slap” it down is the mistake a lot of midlength-novices make.    

Get your foot right on the tail block, move your wieight over your hands to get the nose down and actually push the tail down with your foot whilst moving your weight back, as far as you can reach.  Kinda like a rocking horse type motion.   

At your weight you could duckdive a 7ft x 50L board without a problem if you have the technique to do it.     

Well described.

Thanks guys. My duckdiving is solid so I think I’ll shape the board based on performance rather than focusing on getting out.

I agree. For me, I like rail channels up where I grab the nose also.

When duckdiving a bigger board try pushing the nose down one rail first on a diagional, instead of pushing both arms down at the same time, do one then the other, this means instead of having to displace water from the whole nose area your board cuts in with the rail instead, heaps easier to duckdive a bigger board deep that way, bit like a falling leaf going sided to side, instead of displacing the water you cut through it and get deeper with less effort. Hard to explain but hope you get the idea.