Week 7

May 19, 2017

Progress has been slow this week. The fabricated part did not print correctly; the pinholes in the model were too small and did not show up in the final product. Instead, we tried to use a thumbtack to poke larger holes in a bowl. By putting the alginate in that bowl, then using another bowl to press down on the alginate, we expected to create strands. Unfortunately, the viscosity of the sodium alginate, the width of the bowl, and the flexiblity of the plastic bowl, only resulted in numerous spheres forming just on the other side of the pinholes.

Our alternate plan was to acquire a syringe. This method would be similar to when we used a pipette to squeeze out our alginate solution into a solution of calcium chloride to form long strands, but the thin needle tip and the plunger mechanism would provide us much more precision to create actual fiber-like strings of alginate gel.

This method had its own issue as well. The alginate solution was too viscous for the syringe to extract through its needle. We tried adding water to the alginate solution to make it more fluid, but the syringe still could not extract it. Then, we tried directly transferring the alginate into the syringe using a pipette, then injecting it into calcium chloride, but only beads came out the tip of the needle. Now it was too thin.

We increased the ratio of alginate to water and put the solution into the syringe. This time, we were successful. The result was fiber-like alginate gel.