1st. make sure the legs themselves are solid--no "wiggles". Then make sure the floor is straight. Then, "file down or screw up". Either use files/rasps to take off enough to make the table level, or add feet to the legs with adjustable screws. With those, you drive them in, and then adjust the individual feet up or down.
adding to what Joseph Glackin said, you could buy a pack of plastic chair feet (the ones that you nail in) and sand down the one that is causing the wooble
Here's an easier way, Glue a piece of cork onto the shortest leg. (just measure the distance between the shortest leg and the floor, put something that size under it like a book, just something to use for a few minutes. To make sure the table is level, use anything round and lay it on top to see if it rolls away. ( if it's still not level chose a different size book) If it is level with the book under it, measure the thickness of the book, and cut a piece of cork that size and put the cork under the short leg, removing the book. If your table is now level not wobbley, you can glue the cork in place. )
flip the table over and see why it is uneven first. Possibly a leg isn't screwed in all the way, or a floor protector has come off.... if that's the case fix those problems. If you can't find anything, then consider adding floor protectors (nail in or screw in kind) or cork, duct tape, etc... Generally it was level at one time, so figuring out why it isn't now is the best place to start.
If it is the leg itself that is moving (rather than an uneven floor), you might be able to use a small stiff metal "L" found in the aisle of the big box and/or building supply stores where you find drawer pulls -- there are different sizes available.
1st. make sure the legs themselves are solid--no "wiggles". Then make sure the floor is straight. Then, "file down or screw up". Either use files/rasps to take off enough to make the table level, or add feet to the legs with adjustable screws. With those, you drive them in, and then adjust the individual feet up or down.
adding to what Joseph Glackin said, you could buy a pack of plastic chair feet (the ones that you nail in) and sand down the one that is causing the wooble
My favorite , quick fix is using duct tape: http://www.hometalk.com/diy/repair/furniture/q-tip-fix-a-wobbly-table-with-tape-26365866
Tip: Fix a wobbly table- with duct tape!!!
Here's an easier way, Glue a piece of cork onto the shortest leg. (just measure the distance between the shortest leg and the floor, put something that size under it like a book, just something to use for a few minutes. To make sure the table is level, use anything round and lay it on top to see if it rolls away. ( if it's still not level chose a different size book) If it is level with the book under it, measure the thickness of the book, and cut a piece of cork that size and put the cork under the short leg, removing the book. If your table is now level not wobbley, you can glue the cork in place. )
flip the table over and see why it is uneven first. Possibly a leg isn't screwed in all the way, or a floor protector has come off.... if that's the case fix those problems. If you can't find anything, then consider adding floor protectors (nail in or screw in kind) or cork, duct tape, etc... Generally it was level at one time, so figuring out why it isn't now is the best place to start.
If it is the leg itself that is moving (rather than an uneven floor), you might be able to use a small stiff metal "L" found in the aisle of the big box and/or building supply stores where you find drawer pulls -- there are different sizes available.
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