11-03-2016: This project hit a problem. See update at the bottom.
Following on from my bathroom scales hack I spent this evening sawing and screwing together the platform for it to sit on. This was an urgent task as the bee hive is being moved to a new location tomorrow and so this would be an ideal opportunity to get the scales in place without having to arrange another movement of the hive. Bees are incredibly precise creatures, I am discovering. If you move their hive a just a few meters away when foragers are out, they will return to the location they are familiar with and won’t be able to find their way home! If beekeepers have to move their hives such a short distance they’ll move them a couple of kilometers away for a week and then move them to the new spot.
The scales will sit on a plywood deck raised off the roof’s surface to provide a thermal insulation gap for the hive. I drew up the rough schematic below to illustrate this.
My final design was slightly different, with the pallet being a little smaller than the plywood shelf. This is because, as well as the four strips of ply that keep the shelf securely fitted over the scales, I also added a plywood curtain around the edge of the shelf that hung down below the pallet to prevent rain being driven in to the scales. The ply is 12mm and very solid. I sized it to be ever so slightly smaller than the footprint of the hive so that it will fit perfectly on top. Here’s some build pics:
shelf (upside down), scales, pallet
scales on the pallet
This next one is upside down but illustrates how the four strips of ply keep the top shelf secure. You can also see the curtains. The notches at the back are for wires to exit.
Looking forward to testing this!
Unfortunately there is a major flaw with my design. When Matt went to put the bee hive on top of it it turned out to be unstable due to the small footprint of the scales relative to the hive. The hive is only one box at the moment but Matt intends to add another soon and that would definitely make it vulnerable to being blown over by a gust of wind! Not a desirable situation. I am going to have to look at designing a larger platform to the corners of which I can attach the load cells. This is contrary to the advice on the MakeZine blog that inspired this project, however I cannot see any other solution besides buying an industrial-size set of scales. I want to try the DIY option first before I spend a couple of hundred dollars.
One thought on “Bee hive mass logger”
How are you reading the display when it is hidden under the plywood top?