For anyone who is curious, I opened-up the bore of the chuck a few thousandths with an old watchmaker's lathe... just enough to accommodate the finest of Andy's red thorns and still grasp miniature thorns as well. It seemed pointless to own such a marvelous sharpener with limited capabilities.
Regarding use, I agree with Andy that the MAL is about the perfect sharpener. The fine abrasive applied to the metal ring of the EXPERT is so fine, even finer than the stone found on the RM sharpeners, that it literally clogs with needle dust after every sharpening, requiring some cleaning between needles. As an example, I spun the sharpener about 16 revolutions to produce the dust in the photo; fewer would have been adequate, but i wanted the dust to show-up well in the image. Two "twists" (four revolutions) is all that is required to sharpen cactus thorns.
Discussions on Talking Machines & Accessories
Wonderful collection of sharpeners! I have a couple Peter Greys sharpeners, and had to drill out the chucks to accept the large Burmese Colour Needles. Hope to find a MAL or Universal sharpener some day, though my modified Greys work perfectly.