Able Man wrote:
Hey, gene so; many years ago, while fishing out of a rowboat, we'd use the biggest coffee cans we could get ahold of; buy "a substantial eyebolt" and some fender-washers/ nuts to "jam" the washers a little bit apart from each other... Fill the cans with "Ready-Mix", then wiggle the eyebolt/ washer dealio down into the can and we had our anchors. (After allowing the concrete to "set-up", properly.) Very "price effective" anchor solution.
After thinking about the fact, that a coffee can, could still "scratch up" your kayak, I seem to remember an anchor made in much the same way, as the coffee can anchor; but, using a gallon bleach jug, instead. Just get the largest "eye-bolt" that'll fit through the opening, including the "jam-nuts" and "fender-washers"... Fill that jug/ cement, and you've got yourself THE most economical solution.