3D Printed Ice Block Mould

Challenge: For student to produce, create and 3D Print a working ice block mould, which would allow the students to manufacture their own ice-blocks and chocolate.

Above Prototype One 

Background: This is a work in progress that started with a design that we saw from a student in another classroom at our school.  This student had produced the original print that is shown here.  While the print may look satisfactory the dimension of the print, a width of 35mm and a height of 60mm, meant that the overall product was extremely small, further the height of the sides was only 5mm meaning that the pouring of any liquid into the mould would have resulted in the liquid overflowing the sides and exiting out the gap that was introduced into the print for the stick to be introduced.   The students in my class however thought the idea was worthwhile so they look at this design, and refined it considerably.   The next version that was produced as a result of a brainstorming session, the students

Above: Prototype Two

identified that they could produce an animal themed shape and for a theme.  This produced prototype number two.   While the size issue had been addressed as the dimensions of this print were considerably larger than the print shown above (60mm across with a height of 70mm.   This print had a height of the sides of 10mm.   However, which this may to have appeared to be successful there were two locations below the ears, before the arms of the bear that would have allowed any material to follow out of the mould, rendering it useless.  There will be an attempt to patch this up, for the purpose of testing as the dimensions are much better than the first attempt.   One thing the students have not considered was that while a space has been created to allow the ice block stick to be inserted this

also would allow the liquid material that would be introduced into the mould to flow out.      This led to the third design in this series.  This was based around the students measuring the correct size, which was 70mm across, and 120mm long.  Crucially compared to the other designs this had a height of 25mn which would allow some variation with the mould and the experimenting of producing ice blocks and chocolates. 
Level of Difficulty: High to get this completed successfully the students have already run through various designs and completed several prototype to complete the project.   The designs at present have just had the issue of an adjustment made to the location where the ice block stick is located to prevent material from leaving via this location.
Time frame- Twenty minutes for prototype one, two and a half hours for prototype two and three and a half hours for prototype three.   This series of print is very much a work in progress and it would be anticipated that considerable reworking of this print would be require for it to work in the most successful way possible.
Size: As detailed in the description of each of the prototype.
What we would do differently: This needs to be modified further to be successful.  At present the next step is to run further versions and testing to find a ideal size and address issues such as the location where the ice block stick.
Next Steps for Students: To refine and improve this design so it works successfully with minimum waste and produces a ice block.   The students will start running all three of the current prototype to compare their success or otherwise.