yeah, Ive made one like this too and it works. Looking at yours tho, I'm not sure about the metal washers being in direct contact with the headset cups. Might it not spoil the finish on the cups, and worse might there not be the possibility of the edges of the cups slightly deforming with pressure.
Mine have big blocks of wood between washers and cups, but if it all works ok, then who am I to suggest different.