I hate the sound of plastic rubbing against concrete boat ramps. Last year, just after launching on a concrete boat ramp to go for a night fishing trip, a storm blew up and proceeded to bang the crap out of my keel on the boat ramp. After that, I started searching for a way to prevent that deep cringe from permeating my face yet again.
There are a few commercial solutions available which look very good, but were also too expensive for something that should be considered sacrificial in my opinion.
Then there are the folks who go for JB Weld to build up the high wear areas and simply re-apply when it gets warn thin.
I found a post where someone decided to use Gorilla tape as his keel guard, but that seemed too thin of a layer to really protect against damage.
Being that I do a lot of triathlons and have put too many miles on a bicycle while wearing spandex than I plan to remember, one day while replacing a road bike tire, I realized I had a durable rubber which would be perfect as a sacrificial keel guard for the hard plastic kayak, but the issue was attachment. I cut the beads of the side wall off of the tire (the beads are what hold the tire onto the rim for a 'clincher' style tire) and tried marine goop... bad idea. Then I took the idea of Gorilla tape and laid my sliced up tire within the boundaries of the tape, and applied it to the keel of my Pro Angler (at the time, the boat I had) from the stem all the way back to the beginning of the mirage drive well. That keel guard stayed there until I sold the boat two weeks ago. That horrific sound of the plastic being 'sanded' by the concrete ramps was abated.
This past weekend, I did the same sort of keel guard on my new Adventure and my wife's Revolution and actually took a few pictures. I did use a narrower strip of Gorilla tape this time around, but I don't anticipate any problems with the lesser sticky surface area. Also, I put an additional angled strip around the curvature of the stem as the tire doesn't like to make that curve. I am positive there is a little additional resistance in the water with my keel guard solution, but the slight increase in hull friction I find made up for with piece of mind knowing I can beach the boats without slowly eating my hull
Any bike shop would have some old tires laying around. It doesn't matter if they are filled with holes or even if they had a blow-out. You only need a few good feet of tire and you can have a keel guard that might just last you a lifetime with a few replacement layers of tape.
On to the DIY Tramps... I was not ready to spend nearly $400 on them, but wanted to try them out, so I put on my Google hat and went to work. I wanted my nephew and niece to be able to come out into the world and play on their uncle's sailboat, so I went with the traditional, fabric tramps. I thought about going with the super cheap blue tarp version, but decided against it. What I decided on was trampoline material sold by Fun Spot Trampolines. They were the least expensive for the amount of material. They have them ~160" wide with a minimum order of 3 yards... so I have a ton of the material for under $60 (enough for three Adventure Islands). My wife has a sewing machine, we bought nylon thread, a canvas needle, 10 buckles, and some nylon strapping and went to town. The design is very similar to the Hobie tramps with the notable exception being that the rear bar at of the tramp going to the rear Aka is a piece of 1/2" CPVC pipe. It is considerably lighter than it's galvanized counterpart, and with the load distributed across the bar, really does not have any obvious disadvantages for my purposes... Up next is the splash guard and then perhaps a rear platform for additional cargo on calm days? I only have nearly 2 yards of tramp material left!