Has anyone made adjustable leg extensions to raise a table height? My wife wants me to make her some this weekend for the table she uses for cutting out fabric. She sews and quilts and was silly enough to volunteer to help a friend's daughter by making 20 table runners for her wedding in April. She's talking about 6" maximum rise, and showed me pictures of some sold commercially made of PVC with slots and thumbscrews but I can't see any detail. I looked at the legs and it looks like 1-1/2" PVC will fit over them but how can I attach them in an adjustable manner without drilling thru the legs? Would I put wood dowell inside the bottom for strength, or just a pvc union? Any ideas welcome.