Print using ABS or ASA for max UV resistance. The best color is red or transparent red, as this messes with the small hive beetle (SHB) vision. However, other good colors are violet, blue, orange, and yellow because bees see those colors the most easily.
Your bees will take roughly 2 hours to learn the new entrance and how it works.
The geometry of the entrance is made such that its hard for beetles to enter and easy for bees to fly right in. The beetles will get confused around the edges allowing bees to kick them out.
The opening size of the bee entry is 6" x 3/8". According to Les Crowder this is what bees prefer and allows them to defend the hive naturally.
The holes in the platform are 4mm to prevent bees from crawling through (and thus risking shaving off pollen) but large enough for the beetles to fall though.
I used M5 hex bolt and hex nut for the adjusting slide. You could use a different size with a washer if you wanted. Note that the photo shows an old version without the hardware
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