Spirals 4 and 5

These 2 LED lamps are similar but not exactly the same. I printed both with the same transparent yellow PLA filament. Notice that one of them (spirals4.stl) has the diamond spirals not reaching quite to the top of the lamp. This is because the inner surface is a few mm away from the outer diamonds. I designed it this way because I thought the diamonds would be more prominent if they didn't pick up light directly from the LED light at the lamp's bottom.

After I printed and tested spirals4 it was clear my assumption was wrong. So I tweaked the design to make the inner surface coincident with the diamond spirals. Since the 2 were coincident I also extended the diamonds to the top of the lamp. The result is spiral5.stl. It was easy to makes these changes because all my designs are 1005 parametric; this blog page explains more about that: http://birkbinnard.com/blog/parametric-modeling/

Because spirals5 is simpler geometry it printed in 31 3/4 hours instead of the 44 hours spirals4 re