A German kayaking group each year publishes a list of kayaks giving their volume, etc. It also suggests matching the volume of a kayak to its intended use and paddler by using a rule of thumb which says the total weight of boat, paddler, and gear should be between .3 to .6 of the volume. Applying this to an Anas Acuta results in 190 to 380#, Aquanaut from 217 to 435#, and for a Capella 163 from 200 to 400#.

These figures suggest either people tend to use kayaks with much more volume than needed for day and weekend trips or this rule of thumb suggests boats can carry much more weight than is reasonable for good handling.

My question is whether your experience is consistent with this rule of thumb?

.3 to .6 of the volume??
How are you measuring volume?

Somethings amiss.

400#

I have put 400# in a sea kayak and let me tell ya, it ain’t pretty. no one in their right mind would paddle this much weight around in a reg sized solo sk.

350’s alot and 300 is better.

steve

basis for volume
They are looking at the total volume of the boat.

For example, the Anas Acuta is 288 liters. If a liter is 1 Kg, then .5 of volume translates to 144 Kg. or @300lbs. My SWAG is this rule of thumb results in numbers too big and from sites that give you the numbers on boats it seems there is not a direct correlation between design displacement and total volume anyway. Still, I think you could paddle an AA with a boat/paddler/cargo combined weight of 300# with not big problems.

Well, 300# in a 50# boat with a 150# paddler would mean a 500# total load as used in this rule of thumb so maybe its not so far off…if you meant 300# of gear. If you meant gear and paddler…still not far off.

makes no sense

– Last Updated: Dec-15-07 9:12 AM EST –

Interior volume above the sheer has very little consequence on ability to carry weight but can have a significant portion of enclosed volume.

Unless you paddle with the deck underwater the interior volume measurment is a somewhat useless number. It may be useful to determine how many styrofoam popcorns you can carry.

Carrying that idea further some manufacturers make a "high volume" version by adding more height to the deck which may or may not have practical consequnces for load carrying.

I had a Mariner Express that has lots of freeboard volume, loaded it up to the gills with 125lbs of water and gear for a short paddle down the beach instead of carrying it the two miles. It probably would fit that formula but it was awful to paddle. I'm pretty sure another kayak with less freeboard but larger waterplane shape would handle the load better.

The rule seams logical
When I sit in my 75 lbs Explorer, the boat already weighs in at 300lbs before I add any gear. When I paddle loaded as a guide, the seam is at the waterline and I am definitely over the 400 lbs mark.

Talking about volume and your 1L=1KG comparison, you really need to talk about displacement since 1L of water weighs 1kg. If you had 100 percent load, the boat wouldn’t float. 75% load would mean only the uppermost 25% of the boat would be above water. That probably wouldn’t leave the cockpit above water.

So I would say that the rule correctly identifies that boats can carry more weight than which we would want to paddle with, but the boat would not have the handling characteristics that we expect.

Don’t make it complicated. Use the builders guidelines, they know what they are talking about. Vaughn Fulton

Gotta Show Me…

– Last Updated: Dec-15-07 10:12 AM EST –

Liters are a measure of volume.
Kilograms are a measure of weight.

I can't find anywhere you can convert between the two.

Some boats are measured in cubic feet.
And I can't find out how much a cubic foot weighs either.. ?

Some do, some don’t
I agree each manufacturer should know their boats best and following their suggestions would be the way to go. However, most only give a range for paddler weight and maybe a total weight capacity and some give nothing.

Correct as far as it goes
Yes, you cannot in a normal sense convert between volume and weight, but in this case there is a logic to it since you are displacing a specific liquid with a given weight per volume. I suspect, since I am not a naval architect or boat designer, that when designing boat the calculations give you a design displacement in volume and that is converted to the weight of the displaced water to give you the total loading for hull to be used optimally. In turn, it seems for kayaks you have a window of @50# plus or minus that design displacement/weight. So a percentage of the weight of water for the total volume of the boat might give a SWAG for a reasonable total load. What LeeG said about volume above sheer makes sense too. A boat like the Force has a fair bit of that which gives you more storage room, but the items stored need to be light compared to water and it also means the hull is small compared to rated volume (or so it seems to me).

Anyway this stuff is something to think about when it is 9 F out which is a bit cool for paddling. I suppose best described as idle musings in anyevent.

This type of think make my head hurt…
I just pack it 'til it’s full and hope it doesn’t sink…

The Weight of Water

– Last Updated: Dec-15-07 1:08 PM EST –

See http://www.fourmilab.ch/hackdiet/www/subsection1_4_2_0_7.html for converting between volume and weight -- we're talking the weight of water here, right?

My first thought it that between 0.3 and 0.6 is a pretty big range, and is probably intended to represent the extremes, rather than the ideal. And it is presented as a "rule of thumb" . . . not a precise measure.

The basic point is one I find to be true. The average 140 to 180 lb. person paddling a 17' kayak out for a day tour is paddling a kayak that has a lot more volume than is ideal in terms of windage, tracking, and stability. Add more weight and your boat tracks better, is less affected by wind and waves, and is more stable. In many cases the boat with added weight is also easier to put on edge and feels more stable on edge as well. (On the other hand, paddling that unloaded 17' boat in calm conditions results in a boat that skims along the top of the water, is quick to accelerate, and quick to turn. Kinda fun, I think.)

nothing like getting in the kayak
and paddling. Some kayaks have LOTS of room and freeboard, if you loaded them up to .50 of interior volume you’d be paddling around a HUGE amount of weight.

I’d much rather have a low freeboard kayak that’s a bit wide carrying a lot of weight than a narrow high freeboard kayak sunk down deep with a lot of weight. At some point the skinny/deep kayak sunk down just becomes a hard to maneuver half submerged log.

Geekin out
The strongest opinions here will likely come from folk who rarely, if ever, paddle extended distances. Truth is, it’s very haed to “overload” a kayak assuming “normal” kit and food / water.

At 210 lbs. I’ve done month long solo journeys in Romany’s, Avocets, CH 16 with plenty of comfort. Sure, a laden kayak is less maneuverable, but still fine.

People over anal-ize this stuff. Fact is, any of the larger touring kayaks (Explorer) can carry vast amounts of gear. Any of the smaller kayaks can carry plenty of gear if the right gear and mindset are applied.

I have never seen in over 20 years a kayak sink due to too much gear! Interior volume is perhaps a better measure of ease of packing, and space available.

Buy the kayak that suits your style and learn to pack it. Trying to put absolutes to this is tough, and that’s why I believe many manufacturers don’t. I guess I’ve been breaking the rules for so long they just don’t make sense to me. The smallest kayak has lots of room compared to an alpine climbing pack.

But then, I don’t pack non-essential stuff like folding chairs!

More volume than needed…
> These figures suggest either people tend to use

kayaks with much more volume than needed for day

and weekend trips or this rule of thumb suggests

boats can carry much more weight than is

reasonable for good handling.

I have no clue about the numbers being bandied about, but would definitely agree with the above statement. If you have just 1 boat, you make trade offs. The boat I have has worked for week to two-week trips, but is also one I use for day trips and overnights. On these shorter trips, it is no where near max capacity.

Amen to that Salty …
“The smallest kayak has lots of room compared to an alpine climbing pack.”

I’ve always said a similar thing.

Heck, Kayaks even have more room than some bike packs !

Every boat I ever did got loaded 'till it went under with wet sand weighed on a scale one bucket @ a time … just to see what it would really hold.

2X agree again … I have customers who load their BAJA boats 'till the seam is under (at the start) and these guys tell me they have never lost anything to capsize or things going awash.

IMO, I would have a hard time doing this unless it was 99% food and water for an extended trip. The boats are tanks …

Crazy Creek Chair
Part of my ‘kit’ 90% of the time!

In testing for CWS I use water bottles. I CRAM as many as I can physically get into the boats. we’re talking WATER here. I use 3L, 2L, 1L and mini water bottles till she’s FULL.

This is generally our MAX load figure.

1. Get time

steve

Who are the facts important to?

I’ve seen these volume and weight figures but does anyone really understand them other than by comparison.

I have made 3 long distance trips in a kayak and didn’t weight anything. I wish I could have just before I launched but that wasn’t a priority and I’m sure my kayak exceeed both volume and weight limits.

I ignore the rules of thumb
I’m very light but don’t have a high-volume kayak. With me, the limit is VOLUME, not weight. So the rules don’t mean much to me.

For multiday trips I just took what I thought I’d need, plus a little extra food in case of unplanned layover days.

That said, I finally actually weighed my gear for a Lake Powell trip in autumn. It weighed more than I had estimated, and this was a reduced load due to bringing only warm-weather clothing.

The weight of my gear (this includes the drybags themselves) came to a little over 60 lbs, EXCLUDING water and two paddles. Since I carried about one gallon a day of water, with these items added the total came to over 70 lbs. My Alaska trip load must’ve been close to 90 lbs (I brought heavy muck boots, a 35mm SLR and Pelican box for it, additional water, and some warmer clothing items).

Since I can’t stomach the thought of using a taller or wider kayak, I ordered a longer one for camping trips. It’s not that the weight overwhelms my existing kayak; it doesn’t. But even after cutting down on size and weight of items, I still have more in the cockpit or rear deck than I would like. And I’m really tired of putting off-limits bulky items such as fresh fruit, bread, and chips (think dried cranberries and raisins, dense crackers, and Corn Nuts instead). It gets old after a week. Not to mention it’s nice to be able to bring a book for those unplanned stuck-in-tent days.

But I suppose what I did is the reverse of most people. I chose the “expedition” kayak after years of using smaller ones for camping trips.