Spyderco Endura 4 Scales

About This Model

These replacement scales allow you to customize your Spyderco Endura 4 with any material/color handle choice you'd like. They also forego the subtle finger grooves on the handle, allowing for a more neutral grip that feels better in hand. 

How It Works

There is currently a smooth pattern and a heavily-textured pattern with inlays. You'll need to make a copy of the scale and/or inlay and mirror it to produce a full set. Depending on the filament used, superglue or epoxy can be used to bond the inlays to the scales. The inlays are quite thin and fragile before they're glued into place.

Because of how tight the tolerances are to properly fit the Endura 4 liners, you may need to make slight alterations to the print settings and model scale to fit your specific knife. Some amount of cleanup on surfaces and holes may also help ensure a proper fit.

Recommended Print Settings

Filament: I have tested it with PLA, PETG, & PC Blend. In general, I recommend using a tough filament like PETG or PC to prevent damage if you drop the knife. A more grippy filament like TPU might be great for the inlay material.

Nozzle: 0.4mm

Layers: 0.2mm (can use 0.1mm for better detail, especially on inlays)

Perimeters: 2 (more can cause gaps near the clip screw holes)

Layers: 8 bottom and 8 top layers will produce a solid scale.

Infill: Not tested with infill; print these scales solid. 

Seams: Use seam painter to place the seams on the bottom side of each pivot/body hole. This will place the seams where they won't interfere with the keyed body and pivot bolts.

Skirt/Brim: Use a draft shield to help prevent warping.

Fan: Off

Orientation: Print with the outside of the scale flat on the print surface. Use bed supports to support pivot hole and body hole overhangs. For inlay scales, supports will also be used for the inlay pocket (rough surface makes for better glue joint and is hidden by inlay).

Scale: 100% for PETG. Shrinkage is a significant concern for some filaments; I find 101% scale works best for PC Blend.

Bed Prep: Glue is highly recommended for PC Blend and other technical filaments, since the part prints solid and tend to warp.

Notes and Future Plans

• As always, please be careful and utilize common sense when handling a knife. Don't force things during assembly or engage in unsafe practices. I don't assume liability if you hurt yourself with this model.
• I am planning to add different inlay patterns, including smooth inlays and inlays with smooth spots where the clip sits. I may add different scale designs in the future as well (let me know in the comments if you have suggestions). 
• The very end of the handle does not perfectly align with the stock backspacer, as the geometry there is very fiddly and I cannot be bothered iterating to get it 100% accurate. This discrepancy is not very noticeable on the textured model due to the full-profile jimping.
• This model does not contain a backspacer, as the backspacer on an Endura 4 uses small molded posts to secure against the liners. This isn't something that can be produced on an FDM 3D printer, as they'd probably snap from the high force of the lock spring. If I come up with a way around this fundamental issue, I'll consider adding backspacers.