I would say that Tyvek is too thick for an efficient roll medium --
you would not get many meters of music on the normal sized roll.
Also, its "grainy" structure may be abrasive on the tracker bar and
cause wear.  I say "may" since I have no feel for this aspect, but
someone should check it  out.

A much better material has been used for years in Raffin and other
rolls for 31er and 20er crank organs.  I believe this is Mylar.
It is water resistant, hard to tear, dimensionally stable (doesn't
stretch), low friction, and very thin.  It punches smoothly and
cleanly.

For the record, I've made my own organ rolls using fanfold computer
printer paper, which turns out to be a bit thicker than the Mylar --
I can get only about 5 or 6 minutes of music on a roll. (Admittedly,
I space my notes out about 25% farther, requiring faster cranking).
Thus I'm sensitive to the thickness issue with Tyvek or any other paper
substitute.

At least we can experiment freely with roll materials without having
to re-rebuild anything (but do watch out for tracker bar wear).

Mike Knudsen