Any advice on installing knee tubes?

I have experimented with using both a bladder and water bottles in my Manitou rec kayak and have found the water bottle much easier to use. But I am sick of it rolling around the bottom of the kayak.

I initially thought of velcroing it to the bottom of the cockpit between my legs, but have now just read about rigid knee-tubes glued under the deck between the knees. Some manufacturers make these of fiberglass for fiberglass boats and other people have improvised them from ABS plastic piping or the like. I’m leaning towards a non-rigid solution. Maybe a neoprene sleeve glued on with contact cement and just big enough for a water bottle??

I know a primary concern is to not impede exit when capsizing, and I think the cockpit is large enough for my modest frame and a water-bottle holder. Any other suggestions?

“knee tubes"
That term is more applicable to tiny cockpits where an underdeck tube will actually connect with your knees. You’ve got a big cockpit with lots of room. Try this, get four vinyl or rubber d-ring patches and glue them onto the floor of your kayak in front of the seat, then lace some 3/16” bungie through them or with a plastic hook to make a quick release.

Position them so they can hold the largest item you’d like to hold there. I’ve set mine to fit a small pelican drybox, about 7"x9".

The trick is to rough up the plastic with 60grit sand paper, apply three thin coats of contact cement to the plastic and vinyle patch letting the coats DRY then press together. It will not let go.

You could do the same to the underside of the deck but I went ahead with small pan head screws holding a mesh bag under the foredeck.

here is some I have in some of my kayaks

Best Wishes


Thanks for the suggestions
Roy’s photos show very well-designed knee tubes.

Simple floor holder
Glue a few strips of foam to the floor to form a rectangular frame.

Poke holes through the two long sides, and run a bungie cord across.

I think you’ll find that gluing a tube
(or D-rings, or whatever) under your deck won’t be strong enough to hold a water bottle securely. Nothing glues that well to a roto-molded boat. I finally drilled holes in my deck and attached a tube (made from PVC drain pipe) with screws and nuts to hold my paddle-float and pump.

Under deck bag
Since you mentioned considering a non-rigid option, how about an under deck bag, a la North Water? Holds more than a water bottle, but not too much.

Nice tubes
you got there. Did you buy them prefab and install them? Or manufacture them yourself? I’ve been thinking of installing one, seeing the pics makes me think I should do it sooner than later.

Northwater underdeck bag
swear by it. I have the tabs with the buckles installed on four of my boats and just transfer the bag from boat to boat when I need to.

you do the “Northwater limbo” too?! :wink: