Steel Sheet Holder with compact dual eject buttons (MK3/S)

Continuing on the tradition of the “probably” over-engineered remix series, this is a modified sheet holder optimized for horizontal size. Fits two steel sheets side-by-side with a central eject button mechanism, fitting in just 56cm total (56-57cm working distance). For this feat of engineering, some corners had to be cut ;)

Can be expanded vertically in 1cm increments. Multiple mounting choices using more readily available M3 countersunk screws.

This is based off the “seesaw eject mechamism” version from Chewey (https://www.prusaprinters.org/social/103132-chewey), but modifies all parts aside from the eject mechanism itself which is included here as-is.

Brackets have been optimized for mass printing. You can fit 6 corner pieces on a MK3 sheet (a huge time saver). Brackets have an A/B side, A with two M3 countersink holes, B with a single M3 countersink and a regular M3 nut.

For mounting, my recommendation is to insert a captive nut on the B side. Pair the A side, then fix the support on the surface using an M3 wood screw in the second hole. You can then stack/extend with as many modules as needed over time and attach them using a single M3 metal screw on the first hole (where the captive nut has been inserted).

You can also use a single M3 long screw throughout the bracket sandwich using the most conveniently located hole. Or glue them in place.

The central piece needs 2x rods, 2x buttons, 2x pivots, 2x sliders, 2x arms. They can be printed normally, but then one side needs to be rotated when assembled, as shown:

The mechanism can work fully reversed or sideways.