From the Loftsmith Workshop

One-hand pen and marker cap holder, sized to your caps

Parks your pen and marker caps in a row so you can pull a cap off with one hand and set it back just as easily. Each cap sits in an open-fronted socket on a flat backplate with a screw hole. A little printed gauge helps you measure your caps.

2 parts · 42 g · 179 × 106 × 47 mm

by Loftsmith Workshop

Row of four open cylinder sockets on a teal backplate, with a small flat ruler gauge beside it
Loading the 3D view
Loading the 3D view
No adjustable sizes

Ask for the sizes you want to tweak, e.g. “make the width adjustable”.

Change it in the Studio

Parts

  • cap-dock · PETG · Upright as modeled: flat wall face vertical, socket bottoms on the bed. No supports.

    127 x 25 x 47 mm at the defaults, about 34 g and 52 min at 2 walls / 15 % infill. PETG because the split rings flex every time a cap goes in, and PETG takes repeated flexing better than PLA. The rings bend in the layer plane, so the flex runs along the layers.

  • cap-gauge · PETG · Flat, numbers up. No supports.

    106 x 42 x 3 mm, about 8 g and 14 min. Prints first so you can measure your caps. Any material works; it does not flex.

Print settings

Layer height
0.2 mm
Walls
2 (page default); 3 walls makes the rings stiffer: about 61 g and 1 h 35 min for both parts
Infill
15 %
Supports
None
Notes
Both parts at the default sliders: about 44 g and 1 h 9 min at 2 walls / 15 % infill (dock about 34 g / 52 min, gauge about 8 g / 14 min). Print the gauge first and measure your caps, then print one socket (Number of caps = 1, about 9 g) as a fit test before the full strip.

Hardware

  • 2 × M4 (or 4 mm) countersunk wood screw, 25-30 mm, with wall plug if needed · Screws mounting only. Driven from the front through the end ears.
  • Double-sided foam mounting tape strip · Tape mounting only, on the flat back face. Choose a tape rated for the surface.

Assembly

  1. Print the cap gauge. Slide each cap's open end into the V slot until it stops and read the diameter (a groove per mm, numbers every 2 mm). Measure the cap length with a ruler.
  2. Measure the pull-off force: hang the capped pen by its cap and add weight to the pen until the cap lets go. The mass in kg times 9.8 gives newtons. Enter it in 'Force to pull the cap off the pen'.
  3. Enter cap diameter, length and clip width, then print a single socket (Number of caps = 1) and try a cap. If it is too tight raise 'Printer hole correction'; if it is loose lower it.
  4. Print the full strip upright, with no supports.
  5. Mount it: two countersunk screws through the end ears, driven from the front, or a strip of foam tape on the flat back.
  6. Push each capped pen into a socket with the clip facing out through the front slot. Pull the pen straight up to uncap it; push it back into the cap to recap. If a cap ever sticks, push it out from below through the open bottom.

Good to know

  • The hold and strain figures come from a snap-beam estimate with an assumed friction of 0.25 between the print and a plastic cap. Real grip depends on your cap's plastic, its taper and how accurately your printer makes holes, so print one socket first and tune 'Printer hole correction'.
  • The grip band sits at the socket mouth, which suits caps that are widest near their open end. A cap that is narrowest at the mouth may grip only lightly.
  • Pulling a pen puts the full cap force into the mount. Use screws, or a tape rated for that load on your surface; small magnets are not offered because they would slide on a whiteboard.
  • Not checked in the engine: whether a marker seals well enough when stored in the dock. Check that it recaps fully with a click.
  • Designed for PETG. PLA is stiffer and more brittle, so the rings would need a rebuild in PLA; do not just reprint these files in PLA.
I printed this Remix

Comments