Not a problem...
existing casters are unidirectional on the back and swivel on the front and the front ones LOCK!
Next time I go to HF will get some smaller ones that are the same only rubber. These are heavy duty hard plastic and will slide on the smooth floor if pushed hard enough.
Sure is nice to not have my sweaty forearms resting on the saw table causing me to have to keep cleaning and re-waxing the table top!
Also much better on this ol' back!
~~~GB~~~