A cap lug is a plug like they use in new pipe.It is made out of plastic and tapered,not sure of the size we used on our last buckets.But you dont have to pull the lid off anymore to fill them,just pull the plug.Maybe this will help. www.caplugs.com.:)
The cap plug I use is a ww 15 . The link is just for the picture, how it's used. Beats typing a 1,000 words. I'm thinking about going to one of those black plugs with threads. The ones I'm using loosen up after awhile. But you can always go to a bigger plug.
I have the same buckets you do and I'm pretty sure I use the same size cap plug. I think my problem is I tried to drill too many lids at one time and the hole saw melted the hole alittle too big in some of the lids. Did you put the 1/16th hole in the cap plug or the lid? I drilled my holes in the cap plug, a good thing the first ones were too big so all I had to through away was a plug.
Oh by the way, I saw some of your glow in the dark bees out by Rancho Seco a couple weeks ago.
Since we're on the subject of feeding protein, I wonder if anybody can share their thoughts on the following thread from another board. The topic is whether or not overfeeding of protein will stimulate laying workers in a queenright hive, due to additional nutrition affecting reproductive systems.