This is not a completely new concept. Spool thimbles have long been used on multi-pulley block beckets to increase the pin diameter to better suit typical sized polyester rope. But Dyneema puts a new spin on it. The rope is no longer as wide as the pin, and off center loads weaken shackles and pins, and the block or assembly may be pulled slightly crooked. If there are any sharp edges, the rope will not just contact them but be forced against them by the off-center pull.
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The Blue Wave wheel thimble looks suspiciously like a low friction ring. I wonder if that would work for those of us without metal working lathes.
a. An LFR does not distribute the force across the axle. Not a major problem.
b. An LFR could shift or roll to one side. Potential problem in some applications.
c. An LFR does not have the same deep, narrow groove, and the hole through the center is not straight.
But yes, maybe. Just not optimum and probably no better than a conventional sailmaker’s thimble.
A lathe is not required, though a drill press is very handy. Cut a disks from a sheet of plastic of the correct thickness (hole saw or saber saw), mount it on an arbor made from a 1/4-inch bolt, washers, and nuts, and create the groove. Delrin will be perfectly adequate for most applications. Aluminum can be turned by hand with a light touch and a form tool ground to the correct angle. In fact, hand tools are commonly used on metal lathes for certain details the mechanical leads don’t do well. It works best with special narrow chisels, sometimes graver’s chisels, made for this purpose. Files can also work, though not for a groove this deep.
In fact, a drill press can be fitted with a simple lathe attachment (DIY or $45 from Shop Fox) that allows turning of pulleys, tool handles, and similar small items. I wrote that up too, and hopefully it will appear here soon. I have made some small things, including knobs, soft shackle dog bones, and pulleys that way. A big lathe can be cumbersome for small things. Yes, there is a learning curve, but it is easier than, say, welding.
I feel I should add a warning that a drill press is NOT a lathe or milling machine. While these methods can work for a few light-duty projects in wood or plastics, they are not constructed to withstand high, sustained lateral loads. A few plastic pulleys or wooden tool handles, OK. A small sanding drum or wire brush, fine. Machining of hard materials, no. They are built for drilling.