Honey bee research feeder

Classic Grooved Plate Bee Feeder for Research

This feeder is designed for experiments requiring you to train bees to a specific location or for use in forager choice tests. It is not used for feeding colonies because it only holds about 60 mL of sugar solution.

Fits Fisherbrand clear straight sided glass jar, 60 ml, Catalog number 02-911-773

It is designed to fit any jar whose lip will fit into a ring of inner diameter = 42 mm and outer diameter = 49 mm.

The inner scent well holds up to 1 mL of scented solution, which should not be consumed directly by the bee. The exact volume will likely depend upon your method of 3D printing and its accuracy. 

To use, fill the jar with solution and place the feeder on top, with a deft flick of your wrist, invert the jar. Some solution will come out of the grooves. The more viscous the solution, the less will leak. If leakage is an issue, take 150 grid sandpaper and sand the jar lip as flat as possible. The jar is useful since you can use the cap to cover up the remaining sugar solution.

PRINTING CONSIDERATIONS (for resin printer). I used an Elegoo Saturn. 

1)    Printing it as a solid object on a resin printer generates huge suction forces on the FEP. I could not get this to succeed using a transparent or a clear green resin. The print always failed, usually when pieces were ripped off, even a slow lift speeds. I tried printing it with full supports at a 45 degree angle. The problem is that this takes a long time and half the material is wasted in supports. Also, the surface is not as polished. 

2)    My solution was to make a hollowed model (1.5 mm wall thickness). With a translucent or clear resin, given the small size of the hollows, it is actually filled with resin that you can cure with UV after you remove the model. It will then become solid and stronger. If you use a non-translucent resin, you will not be able to cure the interior. I have not tried this yet, so let me know if it works for you! I tried printing this model at a 45 degree angle and reducing lift speeds and printing it flat on the plate without supports. Both prints worked, although it will take time to tell which is the most reliable. The main advantages of printing it flat on the plate are that it is much faster (1 h vs. 6 h) and results in a smoother finish.

3)    Here are my print settings:

4)    The choice of resin is important. I think an ABS-like resin will be stronger than standard resin, because this can be somewhat brittle. In addition, since the feeder is used outside, the UV from the sun will tend to make it more brittle with time, I suspect.

5)    I think that a filament resin printer could be a better solution in terms of durability and also mass production. The feeder is fairly large and I can only print one at a time. However, the model has very fine details that are important. The grooves are only 1 mm thick and deep. You will need very fine settings to print this on a filament printer.

Here is the feeder on its tripod base. The feeder is printed with transparent resin, processed to be food safe, and then covered with Art Resin.

PRINTING CONSIDERATIONS for filament printer (the best choice, I think)

            After spending a long time making the resin-printed feeder work, I purchased a filament printer. What a different world! I now prefer using FDM printing because it is far easier. For different colors, I just print different colors of PETG. There is, of course, a debate about food safety. The main issue is that bacteria can collect in FDM printing. However, there is nothing inherently toxic about PLA and PETG plastic. In fact, PETG is often used to make plastic bottles. We print our feeders with 100% infill. After use, we thoroughly wash and bleach our feeders, so I do not have concerns about using them for bee feeder experiments. However, if you have concerns, you can coat them with Art Resin. 

            I generally use PETG. It is stronger, more resistant to sunlight, and can be washed in the dishwasher top rack (do not use dry cycle). 

Note the small hole at the feeder edge. This is for a Christmas ornament hangar that you can use to hang your feeder while the Art Resin dries.

Note that the bottom of the feeder has grooves for odors that attract bees to disperse out of. This model has been coated with art resin. Note that there are bridging issues. I did not fine tune it in this print, and I am sure that you can do much better. I would not bother with supports. They can be difficult to remove and are a bit messy.

            Now, let's consider the base. I often use a tripod since it is easy to set up and level in the field. The tripod base holder serves two functions. First, it supports the feeder and prevents it from sliding off as you move it. The grooves in the feeder usually support the glass bottle well. For maximum flexibility, you can just use the version without gluing on the ribs that hold the feeder. You can then position the feeder wherever you wish. The central well holds the scent. Just get a heat-set insert suitable for your tripods, and you are good to go. It helps to use epoxy or superglue to ensure that the heat-set insert is really attached well. All the stress and the weight depend on that one insert.

Notice that the ribs are printed with a skirt. This is useful since the skirt holds each rib in place on the print plate, but it is also very convenient for gluing. I suggest making a template to help you position the ribs. 

Here is a larger version suitable for training a lot of bees.

Enjoy!

James C. Nieh

UC San Diego, School of Biological Sciences

Department of Ecology, Behavior, & Evolution.