To get the job done you could use this string technique or possible look into other glass cutting alternatives like cutting devices. Not only does the bottle protect the candle flame from the wind if you're outside, but it will also keep small fingers from reaching in. Or large fingers if you're like my cousin Thomas who insisted on lighting his plastic fork on fire at our last informal family pot luck. High fives to you kid.
MORE BOTTLE PROJECTS ON APARTMENT THERAPY
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• DIY: Cut and Etch Wine Bottles
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• A Quick Way to Make Everyday Bottles Display Worthy