Many times when people
get their Grip Ring Stem casters, they'll call and tell us that the stems are
too big. They have measured correctly but the casters won't go into the hole.
Sometimes it's the "Grip Ring" itself that is the issue and not the size of the
stem. The Grip Ring is a "compression ring" so as it's forced into the hole,
it's squeezed and then expands and that's what keeps the casters from falling
off the item. So if the stem goes into the hole up to the grip ring and stops,
here's your tip.
Ollie's Tip: Apply a lubricant like petroleum jelly, oil or WD-40 to the stem and especially to the ring. That should do the trick. If it's still tight, take a pair of pliers and squeeze the ring to try to make it smaller.
Ollie's Tip: On the other hand, if your stem fits but seems a little too loose, take a screwdriver and pry out the ring slightly to "expand" it. This will tighten up the installation and the casters should stay attached. If it still is a little too loose, try wrapping tape ( electrical or other ) around the stem covering the grip ring. This should also help tighten it up.