Rattlesnake rattle | print in place | no assembly

Design

I wanted to find out how a rattlesnake's rattle works. There are accurate stls out there, but they require assembly, which is difficult because the shells are so thin. I challenged myself to design one that could be printed in a single piece, based on the limitations of FDM printers.

• Not anatomically correct
• Primary aim: make rattle sound
• Secondary aim: one piece print

Printing

• Just print Rattle complete if you don't want to make any changes
• Suggest using brim because it's rather tall
• Most importantly, use supports everywhere, overhang angle 60° so the supports are only between the segments and not inside. I used 20% support density.
• Other settings: 0.20 mm layer height, 0.44 mm line width, 2 walls, 3 top and bottom layers, infill density 20%
• After printing, bend to separate the segments and then remove the supports using nippers. Shake a few times to wear off any loose plastic and test it.

Suggestions

• Use Rattlesnake body segment to customise the number of segments and length if you want. I recommend raising each segment by 11.29 mm (hmm should probably make that a multiple of layer height…)
• If you're doing that, you could shrink each higher segment by a few mm so the rattle has a more tapered look
• I think it sounds more realistic when the end is open (only print the body segments, don't include the end) based on what rattlesnake videos sound like.