"ameijers" wrote in message
John

When you buy an outdoor table of the size in question, the glass is
(usually) not tempered....


Not true. Only a fool would buy a non tempered glass for a table top.

http://www.sears.com/sr/javasr/produ...00&tab=spe#tab

http://www.sears.com/sr/javasr/produ...00&tab=spe#tab

http://www.sears.com/sr/javasr/produ...00&tab=spe#tab

http://www.walmart.com/catalog/produ...uct_id=4244442

http://www.kmart.com/catalog/product... tegoryId=466

http://www.kmart.com/catalog/product... tegoryId=466

You may find this interesting also.
http://www.glasstopsdirect.com/faqs.php
3. Does the glass need to be tempered?
The ½" and ¾" inch thick glass tops do not need to be tempered. We do
however; recommend 3/8" thick glass tops to be tempered for extra strength.
All of our 3/8" thick glass tops are tempered.



http://www.eco-furniture.com/docs/li...ffeetable.html