Fourth day for our agar agar tests. We are back after designing some modifications to have a decent heated syringe and nozzle. Hopefully this gives better results after day #3 disaster.
We are using a common 3d printing heated block, with a convenient air fit connector that has both threaded sides magically equal to our cartridge and heated block ODs.
Today we have two goals. First one test if the heated nozzle is enough to avoid clogging issues. Thus test to print a basic cylinder shape. To validate if the new heating design works we are going to run two tests. First load the cartridge with agar agar and see if after 30 minutes the tip is clogged or not. Later run an stalactite test. An hour dripping.
For this test we are using our first day#1 recipe: 100gr of water 2gr of Agar agar. Heating the capsule at 55ºC.
First thing we wanted to try was to hold the liquid into the hot extruder. FAAAAAAAAAAIL. the liquid keeps running without any external force. Their might be some air leakage somewhere. Or maybe the nozzle is not properly screwed to the cartridge body.
After the first experiment success we are going to run some sealing tests. Filling some cartridges to probe that water should not flow through an open nozzle. This is a similar experiment to the upside down glass of water. Definitely there is something wrong with the nozzle sealant. After tighten it, it stops dripping. Finally some good news.
After the previous issues, we tested to run a basic print with awful results. Controlling the flow with AE is extremely inaccurate, specially for low viscosities. We decided to stop the experiments and pursue a better hardware control for extrusion.
Agar agar is a cool material to experiment with. Adding temperature to work with it is pretty interesting too. But not having the right hardware to follow the experiments makes it pretty difficult. For that we will keep this experiments on-hold until we got a decent extruder tech that permits having a constant flow. Luckily we will be back to play with hydrocolloids sooner than later.