The poles are 21 cm long and the bases are 9 cm square. The poles are designed for a gap of 18 cm between inside surfaces of the bases. The recessed circles start at 7cm in diameter tapering to 4 cm at 1cm depth. The frame in the pictures were made with Laywood which necessitated 4mm perimeter and 40% infill settings for the poles but regular settings (1mm perimeter and 20% infill) for the bases. This accounted for about 60 grams per object (a pole or a base) for LayWood. I also utilized variable temperatures to get the tree ring look of real wood. It should be noted that the higher temperatures tends to weaken the structure. The frame was tested for sizing and stress checks with HIPS prior to attempting with Laywood so you can use cheap HIPS with regular settings (although not to look like wood though). I used common fabric-like styrofoam packing cut in circles as shock absorbers between the hourglass itself and the bases. The hourglass itself was purchased at a local Pottery Barn. I can't find a link to the one we bought.
This frame was printed on a Lulzbot Taz5.