If the hatch is wooden, kinda. Wooden objects dropped into magma disappear (doesn't work the other way around).
E: I was bored and created another exactly day-long oscillator:
Cart does 2 oscillation cycles each on both 3-ramp incrementers and changes track in the south.
▒▒╗╔▒▒
▒║╝╚║▒
▒=++=▒
▒║╗╝╚▒
▒▒╚=╚▒Because placing a 48x or 50x bumper to 25 or 24-step setups would be easy.
Track/ramps in pink, medium track stop in yellow. 5x4...Feh. Could be smaller.
If you replace the SE NE ramp with NS, you can place a minecart in the SE wall square that will accept 32620*weight westward and 19560*weight as northward inputs once a day i.e. Could use 30 weight input cart, 83 weight output cart on high track stop to make a month counter.
(Alternatively, could install pressure plate on the NW track east of track stop.)
And for something a little different:
|
|
╔
╗╗
╚
║╗50k (- iirc 17
) step
repeater {timer, as it won't be able to pay 10 floor friction to move on corner/plate}, for those pesky hunger, thrist, and mood things.
Counting counterclockwise from the sole cart on ramp, the materials are oak (hits next cart with 4890 every step, gets pushed sideways by 2 every step), chestnut (hits next with 3390), oak (hits next with 1048), kapok(hits next with 38).
If they're all same material, makes passable 217-step bridge waver.