MIMF

I have a pencil sharpener which looks like this and so much quicker and easier than a regular one:


I wonder if the same mechanism would work for a peg shaver? I wonder if it'd be possible to alter one of these pencil sharpeners to do a peg taper? Anyone ever tried that or similar?

It should work but it would require making new end bearing brackets for the spiral planer heads to hold them at the correct angles. I worry that the planers are only long enough to cover the length of a pencil point, about an inch. The planetary gear drive mechanism at the narrow end might also have to be rejiggered to accommodate the much longer taper.
X-Acto still makes parts for the Boston style sharpeners http://xacto.com/products/office-soluti ... tail/R1827

Shaving an ebony peg that is maybe 2 inches long would take a lot more strength than a cedar pencil with a 1/2" long tip. I made a peg shaver similar to the commercial version that uses a single blade set at a 90 degree angle to do a scraping cut. My home made version didn't work that well.

The internal helical cutters of that type of pencil sharpener are usually fixed, and are way too steep of an angle for instrument makers. You would have to pull out the internal mechanism to see if there is any way to change the angle of the cutters.

Barry, by 90 degrees do you mean perpendicular or tangential to the outside of the peg? It should be tangential, like this:
https://www.stewmac.com/Luthier_Tools/T ... haper.html
I made a quick and dirty version out of a maple block and replacement blade when I needed a one-off peg for a cello that was too big for my violin peg shaper. It worked great!

Jim, my post was wrong. I made the blade tangential to the peg. My jig was not sufficiently rigid. It worked but not that well.

Are those stewmac ones any good? Any advantage of the push down knob design? I use one of these:

That is the standard version. I use an adjustable one like this: https://internationalviolin.com/Product ... lin--viola that can be adjusted to handle pegs from smaller violin to viola size. There is a separate model which handles cello-sized pegs. Both versions work fine, just depends on what range of peg sizes you made need to fit.

The one I made for my one-off cello job was basically just like the one in your pictures, except the body was oak and not brass. I reamed a tapered hole, planed off the top, and clamped a replacement blade on top. It did its job.