this toothbrush squeezer works by worm drive.

to assemble push crank through top gear to get it to fit . the make sure the  crank goes through the top holes in the frame. then hold the top gear in place as you slide the crank through the holes on the frame and the top gear. the crank will snap into place.

make sure you push the crank from the side of the frame opposite the tube insertion slot on the frame.

slide the endpiece into the frame snapping it in place,

then, slide the bottom gear through the roller to the end, with the cutout on the gear facing the end of the roller with the flanges, 

then, holding the endpiece (both to hold while inserting the roller and to align the endpiece and roller) slide the roller and gear into and through the frame.  the end of the roller inserts into the endpiece , it will snap onto the roller.  be sure the grooves in the roller go into the endpiece are aligned.

to start, line the slot in the roller with the slot in the frame, then you can insert the tube through enough to start winding.

if tube is already half empty or so, you can slide the tube end through the frame and the roller, as far as you want, up to the to of the tube and start cranking.  you can then slip the end of the tube hanging out into the roller into the slot in the frame for this purpose, and pull until it is taught. this keeps it all shorter than if it was just hanging out the back. but that is up to you.

to remove, you push the roller out of the frame far enough to remove the tube.

be sure to push the roller back into the endpiece for the next tube.

careful. this squeeze can squeeze so tight that when you release take off the cap the paste shoots out. so i recommend not squeezing so tight.

no supports.