How to convert volumes of older boards to todays' volumes?

[speedysailor]

[pueno]

[gk109]

I weigh 200 pounds and have sailed a bic veloce that is around 140 literes and 293cm and currently have a moderen 138l 258cm 72w board. the bic was one of the no nose boards and is unstable to tack as there was not alot of volume up in the nose. It floats me just fine and is tippier from side to side. my 138 is more stable side to side, more fun to jibe and an all around better ride. you do however feel the lack of length when tacking. I guess what im saying is volume is volume, they both float the same amount its just how its distributed leads to different ways the board reacts. In my case neither board tacks all that well compared to the other( i have no problem tacking either) but where they are both a little unstable for and aft the width in the moderen board settles it side to side and makes everything easier. At my weight 138l is plenty of float and i use up to a 9.5 on that board, if iwas to only go to a 7.0 id be looking in the 115 to 125 range. and i bet the planing threshold would be about the same as your old board.

[mez32522]

My best sailing bud, at a svelte for him 215, rides a 109 in light winds, and a 99 for winds over an average of 21.
He easily uphauls the bigger board, and can stand on the smaller until he starts pulling.
109 is the Joker from Mistral.

[GURGLETROUSERS]

The last two days we've had very gusty and lully cross off winds, with a useful groundswell and surf. At 82 kilos and with 10 kilos of rig, it comes to 92 kilos, which equates to 92 litres threshold of float.

Day 1. Cross 94 and 5.5 rig, just able to stay up with much wobbling, when caught in dead patches in surf. Not really nice at all, and lots of pumping to pull onto plane.

Day 2. Identical conditions but used Cross 118 with same 5.5 rig. Much easier, and kept enough drive in lulls to remain steady. The main eye opener though was the way the bigger board just kept on planing. It easily caught and passed a friend of equal weight who was still using his 94 litre, when he couldn't quite hit the planing threshold. It surprised both of us.

Using the bigger board equated to much more fun. (It even recorded a similar top speed to the 94, of 25.7 m.p.h. and it's supposed to be a slow board!)

Some of us are rapidly coming to the conclusion that a reasonable excess of volume is a good and rewarding thing, in less than perfect conditions. That Jingbritzen 11.5 is moving ever higher up the priorities list!

[boardsurfr]

To calculate the volume that allows uphauling without the board sinking, you need to take a few more things into account than just the sailor and the rig. The board itself also adds a weight equivalent to 5-10 liters; a wet board can easily way several pounds more than a dry one. Similarly, the rig will be wet, and a bit heavier. When starting in low wind, the wind pressure will actually press downward and add more apparent weight. Finally, don't forget the weight of the harness, wetsuit, and booties.
So, for a 200 lb (90 kg) sailor: 90 l body weight + 10 l board etc. weight + 10 l rig = 110 l. This means that a 110 l board will be completely or almost completely under water in the final stages of uphauling. I weigh about 90 kg, and my Fanatic Skate 110 (which is very light) does indeed tend to sink completely when I uphaul it.

The important thing to remember is that the liters above the calculated limit will make uphauling a lot easier. 10 extra liters make uphauling easier, but for average-weight non-experts, 20 extra liter are needed to get to the point where neither the nose nor the tail tend to sink if the feet and weight are not quite perfectly placed. Again, this matches my experience - a 120 l boards is uphaulable ok, a 130 l board is easy.

This matches the "2/3s of your body weight" formula result (133 l) quite well. In effect, this formula takes into account that (a) you need some extra volume to uphaul without having to worry about nose- or tail dives to much, and (b) that heavier guys need a bit more extra volume. I think it's a very good starting point to determine the board size required for reasonably easy uphauling.

[GURGLETROUSERS]

Agree that uphauling requires extra volume to avoid sinking, above that of the stand and float threshold, but not sure you should count the weight of the board if the water is sloshing about at deck level.

It's the volume for most satisfaction in gusty conditions that's the problem. Is it better to be planing for most of the time on a bigger board, at the sacrifice of some throwabout ability, or slog about half the time, for the extra rush once up and going?

I'm sure most have their own take on things, but comparing the two, the bigger did plane earlier. Perhaps that only holds true for boards closer to your threshold float level. At higher volumes the shape is probably more important, as already suggested. Modern should be better.

[keycocker]

With shape -sharp rails are the key to fast planing.Look on any race board

[mez32522]

145lbs. with 5 mil wetsuit, which may sometimes get wet.
Easy uphauling......90 liters.
Can do uphauling...80 liters.
Tough uphauling, several tries...73 liters.
61 years old, stiff, bad balance.

[GURGLETROUSERS]

But if there's a big lull with insufficient air movement to do a lightwind waterstart Mez (lower mast and sail clew hold) on your 73 litre board, what's the point of uphauling it?

It'll still be underwater and unable to go anywhere.