Not quite sure if you fully understand the danger here. The large 15/16 inch diameter steel ring that comes off of the remainder of the wheel to allow the tire to slide off can literally blow off of the assembly when you are refilling the new tire with air. If this ring is not properly seated in the grove ALL THE WAY around it will very likely come off.

Now figure out the surface area of one side wall of the tire and multiply that by whatever pressure that you are going to inflate the tire to. You can easily get to over 15,000 pounds of force. If that steel ring comes off with that much force behind it and you just happen to have your arm in its path, (like when holding the air hose on the tire fill valve) You will be very lucky if a good doctor can reattach it. Let alone your head if you happen to be watching the valve stem area at the time.

The "cage" mentioned by COILOVER, is just that. It is a very substantial steel cage just large enough to place the tire and wheel inside. The top is chained or otherwise secured shut before re-inflating the tire. It is designed to catch and stop the ring when it comes off.

Many years ago we would place the tire and wheel assembly on the floor ring side down believing that this procedure would protect us. One day I was watching as a ring blew off lifting a 120 pound tire & wheel assembly 6 feet into the air. The guy filling the tire was badly bruised with several stitches. After that it was always a cage.

1941 Chevy Master 3/4-Ton
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