While doing some googling I ran across some old & interesting patents
for fishing rods. One just happens to be a retreaval system filed in 1947
somewhat (only somewhat) like what was in RodMaker.

[www.google.com]

There is a LOT of funny old gizmos invented way back when too! I'm going
to put a page on my website with a ton of links to old patents relating to
or especially for fishing rods.

Raymond Adams
Eventually, all things merge, and a river runs through it..

I just read the patent information text. Very interesting concept. Instead of a simple denture cleaning tablet, they utilized a series of perforated cylinders to create a "torturous path" for the water to reach the deployment device to prevent it from releasing in the rain or in shallow water. And, a spring that could only be compressed to allow a direct flow of water in when the pressure (from water depth) reached a certain point.

I'd put mine up against theirs any day, but have to admit that had they had access to denture cleaning tablets back then they might have come up with the very same thing I did. Denture cleaning technology took a previously cumbersome idea and made it a reality. Who would have thought such a thing.

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Hat's off to the tinkerers and inventors of old and new.

While I was checking out many old patents, many things made me laugh
but others were quite interesting and thought provoking. Many things we
use today have roots going back quite aways. More so than I thought and if
it wasn't for many inventors we might still be throwing rocks instead of jigs.

Raymond Adams
Eventually, all things merge, and a river runs through it..

While I have no idea about comparative costs or dissolve rates, another product that is similar in intent to what you are doing in the retrieve system is the dissolving plug used on some automatic life preservers. Since they support the pretty strong spring load of the triggering mechanism, they have to be pretty tough.

That might work even better. I was just going for something readily available and inexpensive, that would still do what needed to be done.

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