Egg Marking Lathe

My wife has been getting into egg painting, and one of the tools she wanted was an "egg lathe", basically a tool to hold an egg firmly, and let you mark along its length in straight lines, or rotate the egg and make equatorial markings on it for positioning the art.  

This is what I came up with!  It uses a spine of 2020 extrusion, and T-nuts with screws for structure and to let the clamping portion slide easily.  The clamping action is powered by a single rubber band, you can adjust that for the amount of hold you want on your egg.  I printed mine in black Overture PETG, but there's no reason that PLA or whatever else you've got in your printer wouldn't work.  No supports are required.

The headstock and tailstock have eight divisions on them for easy laying out of your longitudinal markings.  

For this build you will need, in addition to the prints - Two small pieces of 2020 extrusion, the size is not critical, cut to fit your preference.  For the lathe itself, it could be a meter long and would work the same way.  For the marking table, you'll need to adjust the length as appropriate for whatever marking tool you wish to use - the center of the marking tool needs to be centered on the egg.  The T-nuts are used in this assembly to let you adjust that as needed, just loosen them a tad and you can adjust the height of the marking table.  

8x 4mm T-nuts
8x M4 x 6mm screws
8x M4 washers
1x Rubber Band