Printing a case insert.
StashGrid gives you the geometry; your printer, slicer and filament decide how it turns out. The biggest surprise for most people is size: none of the supported inserts fits a 256 mm build plate in one piece, so plan the split before anything else. Then print a small test section, and only then the whole thing.
1. Export the right file
Finish the layout, wait for processing to finish, then open Export and download the STL. Each layer is its own file: for the Apache 3800 that means an upper STL and a lower STL, exported one at a time, with the case and layer in the filename.
The editable layout stays in your browser. Keep the STL for printing, but don’t treat it as a backup of the design: the designer can’t import an STL back into an editable layout.
2. Check your build plate
Import the STL and check it reads in millimetres (STL files carry no units, so a slicer can guess wrong). Don’t scale it down to fit your printer: that shrinks the gear pockets too.
| Insert | Bambu Lab A1 mini 180×180 | Creality Ender-3 V3 SE 220×220 | Prusa MK4S 250×210 | Bambu Lab P1S, X1C, A1 256×256 | Creality K2 Plus 350×350 |
|---|---|---|---|---|---|
| Apache 3800 lower | 6+ pieces | 4+ pieces | 4+ pieces | 4+ pieces | 2+ pieces |
| Apache 3800 upper | 6+ pieces | 4+ pieces | 4+ pieces | 4+ pieces | 2+ pieces |
| Glock Factory Case | 4+ pieces | 4+ pieces | 2+ pieces | 2+ pieces | One piece |
| Pelican 1170 | 2+ pieces | 2+ pieces | 2+ pieces | 2+ pieces | One piece |
The drawing below shows why for the Pelican 1170: at 271 mm it is just too long for a 256 mm plate, at any angle.
Bambu Lab A1 mini
180 × 180 mm
Split into 2+ pieces
Creality Ender-3 V3 SE
220 × 220 mm
Split into 2+ pieces
Prusa MK4S
250 × 210 mm
Split into 2+ pieces
Bambu Lab P1S, X1C, A1
256 × 256 mm
Split into 2+ pieces
Creality K2 Plus
350 × 350 mm
Fits in one piece
3. Split a big insert
Most slicers can cut a model and add connectors; the PrusaSlicer cut tool and Bambu Studio’s cut tool both do. Where you cut matters more than how:
- Keep seams out of pockets. A cut through a thin wall between two cutouts leaves a joint that flexes every time you pull the gun out.
- Cut across the short side when one cut is enough (the Pelican 1170 and the Glock factory case on most printers).
- Avoid the Apache handle slots. The upper insert has four; a seam through one weakens exactly the part you lift by.
- Check the connectors. Default dovetails and pins are sized for the slicer’s idea of your printer. Print one joint on its own first.
People who print these without a designer describe splitting as the worst part: one tester split a StashGrid file and added dovetails in Tinkercad by hand. It works, it is just slow.
4. Material and slicing
There is no single right filament. A common approach among people printing gun case inserts is a rigid body in PETG with a softer TPU layer wherever the insert touches the gun. We haven’t tested materials ourselves yet, so start from the filament maker’s data for the temperatures your case will see: a car in summer gets hot.
Start from your printer’s and filament’s default profile, then look at the layer preview: walls around pockets, pocket floors, and anything bridging. On most surfaces, pockets have a small bevel at the top edge (2 mm deep, 1.5 mm wider) so gear drops in more easily.
5. Test before you commit
Cut out one pocket and one joint and print just that. Check the gear goes in and comes out, the joint closes flat, and the wall around the pocket is stiff enough. It costs an hour and saves a day.
Then print the insert, put it in the empty case, and look for rocking, rubbing on the lid, and sharp edges before loading it. For the Apache, check both layers stacked. Hold off on glue until you are happy with the fit.
We haven’t published our own fit tests yet. If your print is off, check scale and printer calibration before you blame the design. Back to the designer, or read the FAQ.