These are teaching models of a long, thin representation of double stranded DNA with varying lengths (294 or 420 bp) and varying end-attachment styles (handles or magnets). The end-attachments aid students in holding and interacting with the model. Disc magnets with a diameter of 1/8” or 1/10” and thickness of 1/16” can be purchased online from K&J Magnetics and glued into the magnet sites. The model is designed to go with a teaching module on DNA supercoiling. The models can be accompanied by Nucleosome and H1 histone models to demonstrate DNA packaging in the cell. The printable models are already uploaded to Shapeways.com in the MacroMolecules shop under the names “294bp DNA (handles)”, “294bp DNA (magnet)”, “420bp DNA (handles)”, “420bp DNA (magnet)”, “Histone H1 protein”, and “Nucleosome”. The DNA models have been printed successfully using these parameters on Shapeways’ laser sintering printer in the Elasto Plastic material, while the accessory models have been printed in the Strong & Flexible Plastic, and Stainless Steel materials.

Prints were designed for the following sizes: DNA-294bp-handle-supercoil – (0.844 x 0.792 x 30 cm) DNA-294bp-magnet-supercoil – (0.844 x 1.154 x 29.998 cm) DNA-420bp-handle-supercoil – (28.862 x 14.99 x 29.052 cm) DNA-420bp-magnet-supercoil – (29.93 x 12.304 x 29.754 cm) H1-protein – (2.77 x 0.5 x 1.458 cm) Nucleosome – (3.912 x 1.59 x 1.59 cm)