The idea of printing a pen barrel isn't new but I wanted to use a different approach to engrave images onto the surface of a pen barrel (for pen kits or sleeves for any existing pen or pencil), by using flexible filament (TPU) and 2 different software components (one to map any image onto 3D barrels, saved as STL files and the second software to design tessellation patterns for images to map onto the cylinder). They came out beautifully, they are easy to configure and the flexible TPU filament makes a great pen barrel.

So, to begin with, there are dozens of different types of these pen kits ranging from elegant to truly hideous (depending on your taste in pens) …

Pen kits are available from many sites.

One site is: https://www.pennstateind.com/store/PKFP5010.html

The instructions for this particular Vertex pen kit can be found here:

https://www.pennstateind.com/library/PKFP50xx_ins.pdf

I picked a specific pen kit type (Vertex-Magnetic). It takes a 10.5 mm brass tube of 2 3/8 inches long (60.325 mm).

Using a software called PhotoToMesh, that generated the cylinder for the pen barrel with an image engraved surface, a flexible filament (TPU) and a Flashforge Finder 3D printer, it was easy to design and print an image engraved barrel that fit snugly enough to hold the brass tube inside of the 3D printed barrel without needing glue.

I used is PhotoMesh V7 from Ransen software (I bought a version for about 55$ because it’s really useful software) and Tesselmaniac (30$) to design some unique patters to engrave. http://www.tesselmaniac.com/tess/TesselManiac.html

Specifications for a pen barrel for a Vertex pen kit.

• Get a Vertex pen kit

• It will take about 1 hr 8 min for 1.25 meter of filament using settings for TPU (that’s why it seems longer than it would otherwise take to print this in PLA) to print the barrel for the kit.

• Bushing for Vertex pen kit is 11.684 mm or .460”

• So if you want an outer diameter of 11.684 and an inner diameter of 10.5 then make the diameter of the cylinder (in MeshPhoto) 10.5 + 2(0.6) = 11.7 and 60.375 (a tiny bit proud of the brass tube whjich is 60.327 mm or 2 3/8 inches). That means that the wall thickness of 0.6mm will give an outer diameter equal to the bushing diameter (if you were turning the pen part on a lathe). To get the correct outer diameter at the ends, do not invert the image.

Procedure:

• Open PhotoMesh and select Cylinder from the solid shape tab

• Enter the dimensions of the pen kit blank. For a Vertex pen put in 60.325 for the height 11.684 for the diameter of the Bushing for the pen kit I used 11.7 diameter and wall thickness of 0.6mm and a Mesh Height of 0.7mm (not inverted). You can generate unique tessellation patterns to engrave using Tesselmaniac (see below)

• Next tweak the image contrast, size, position on the cylinder and sharpness settings until you get the look that you like (live preview window).

• Save as an STL file.

• Print out the STL file of the pen barrel and seat the brass tube (in one smooth and quick move).

• Assemble the pen parts around the brass tube and barrel.

• You can have a longer tube and cut off a part of the tube to make inserting it in the tube easier, or insert the tube over a hole smaller that the outer diameter of the 3D printed part (so it slides on easily without compressing the 3D printed barrel)

Other uses:

• Make any pen kit using these same approaches. The dimensions for the tube length, diameter, bushing size etc. are in the kit instructions.

• Use a printed barrel as a sleeve on other existing pens or pencils of any type

• Print an outer cylinder to fill with clear or colored Alumalite for turning on a lathe

• Use the barrel as a rolling print stamp or clay impression maker part.

• I printed the part with TPU so that it would be flexible for a nice pressure on the brass tube.

Other projects that describe printing pen barrels:

https://www.thingiverse.com/thing:195277
https://www.thingiverse.com/thing:1196766
https://www.thingiverse.com/thing:17339