The industry sizing calls it 70mm for a standard mouth jar which is indeed 2 3/4 inch. Hole saws can be purchased at Lowes/Home Depot but you will also need to sand out the hole slightly so the 70mm lid will fit in the hole. I use a "flap wheel" sanding disk I got off of eBay:I am making a feeder for my Nuc. Just a board with 3 jars on top.
My question is what size hole bit do I need to do this? Quart Mason jars.
Check out the jar feeders on this page: http://scientificbeekeeping.com/fat-bees-part-3/My question is what size hole bit do I need to do this? Quart Mason jars.
With the hardware cloth, I turn the inner jar lid upside down to get it closer to the wire, work s great and no leaksI found the easiest solution, after some trial and much error later, was to simply drill the hole at 3", a common size from HD. I then staple a 6" × 6" piece of #8 hardwarcloth over the hole to set the jar on. The bees access the syrup through the screen. This allows me to quickly change or refill the jars without the bees coming out to say hello. The space created by running the innercover upside down allows for a pollen patty to be placed underneath directly on the frames. Been doing it this way for two years with no problems.
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