The twin beds in my 3100 always seem to move around a lot. I tried anti slip paint, etc. and nothing seemed to keep them in place. I recently tried some 2" 3M anti slip grit tape. I cut three 4' strips and merely peeled and stuck them on the particle board under the mattresses. It works extremely well in keeping the mattresses where they are suppose to be. the 3M product is not cheap but if it works what the heck!
