I have never sealed the inside of a box either but once bought a few boxes that had been varnished inside. They are a lot easier to scrape the burr comb in the honeyhouse when extracting. Can't say it would be worth the time and expense though and I definately wouldn't use an oil based product without allowing a lot of time to air out. Has anyone here tried the 3:1 parafin gum rosin dip? I have heard that they can get a bit tacky in the heat.
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