DIY composite cork

[jurelometer]

don't much like the feel of burl, compared to natural cork,
but absolutely LOVE about 3/4" at both ends for durability

Agree.  Burl/composite is also not as grippy if it gets slimed.  High quality natural cork is as nice as it gets for lightness, comfort and grip. Composite gives up a bit in those categories in order to gain durability.  I haven't built a rod with natural cork since I found composite.  But have to admit that I still have bit a fondness for the feel of a natural cork grip on a fly rod.

[JasonGotaProblem]

I'm curious about this "suberin" stuff. This talk of it working better in sheet form because of compression needed, I assume, is the reason composite cork still  comes in ring form. I assumed it was to imitate the real thing. I'm thinking now that was just the easiest way to do it.

But it also leads to a potential different version: metal pipe instead of pvc, all-thread rod instead of smooth (still both greased), and a nut and washer of ideal dimensions that can be tightened down for compression (any binding agent on the threads would be troublesome for removal of the nut though). And since the pipe is metal it can be heated with a torch or heat gun. Less precise than the oven but less spouse-rage too.

This idea is developing beyond shower musings. It's becoming more reasonable, even despite some initial pessimism on here.

[jurelometer]

Commercially made   composite rings are cut from stock.  The are not formed as rings, as each would have to be compressed individually, and still would have to be cut/trimmed down past the inevitable voids on the surfaces.  They also  sell   blocks of the stock, BTW.

Don't think the hot pipe approach is going to work for the reasons already discussed in this thread. If you want to improve your odds, mebbe research on how the real stuff is made, and see how close you can come to approximating the process.

My apologies if you already know this, but don't take a torch to galvanized pipe.  The zinc fumes are somewhere between harmful and fatal depending on the exposure. It is an occupational hazard for welders.  Look up "metal fume fever zinc" on your your favorite search engine. 

-J