Pen Press Blocks
thingiverse
You can assemble a pen press by placing the blocks on the press and forcing it in place, as recommended by Penn State's product guide which you probably downloaded when purchasing from them. Print this template out with 50-70% infill because assembling a pen puts good pressure on your tool so strong plastic is required for proper fit.
Download Model from thingiverse
With this file you will be able to print Pen Press Blocks with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Pen Press Blocks.