Modular Precision Mini Vise – Multi-Grip System

I’m done with 3D-printed vises that feel like toys. 

Plastic threads are crunchy, imprecise, and they eventually snap. I wanted a real tool.

Let’s be honest: while a ball screw would be optimal, a standard M8 steel rod is the perfect sweet spot for a DIY vise. It’s precise, cheap, and incredibly tough. I tested this build with a torque wrench, and it held up to 60Nm of force before the PETG-CF even flinched. 

If you’re tired of plastic-on-plastic friction and want a solid, modular system that actually performs, this is for you.

FEATURES

• Fully Modular: Choose your own 6mm guide rods and M8 threaded rod length. Baseplates for 100mm, 125mm, and 180mm setups are included.
• 3-in-1 Grip System:
  • Pin Grip: Use 6mm steel rod scraps as pins to hold round (3 pins) or irregular (4+ pins) objects.
  • PCB Mode: 1-axis turnable grippers that lock into place automatically under clamping pressure.
  • Soft-Grip: Standard jaw inserts included for printing in TPU 95A to protect sensitive surfaces.
• Extreme Rigidity: Tested in PETG-CF, the design withstood up to 60Nm of torque before significant deformation.
• Smooth Operation: Designed for two 608 bearings and an integrated M8 washer groove for smooth clamping.

ASSEMBLY AND POST-PROCESSING

• Hole Optimization: The 6mm pin holes are intentionally designed slightly undersized. Clear them with a 6mm drill bit after printing to achieve a perfect professional friction fit.
• Baseplate Mounting: If using the optional baseplate, the front (static) jaw is secured from the bottom using two M3x8 screws and two M3 heat inserts. This keeps the vise contained and aligned.

BILL OF MATERIALS

Core Hardware:

• 2x 6mm Steel Rods: 2x (100, 125 or 180mm)
• 1x M8 Threaded Rod: 1x (Matching your steel rod length)
• 3x M8 Nuts (Two embedded during print, one for assembly)
• 1x M8 Washer (Placed in the groove between the static jaw and turning knob)
• 2x 608 Bearings: 
• 3,4,5x Vise Pins: 6mm steel rod scraps cut to approximately 20mm pieces

Baseplate Hardware:

• M3 x 8mm Screws: 2x
• M3 Heat Inserts: 2x

PCB Gripper Hardware (Optional):

• M4 x 25mm Screws: 2x
• M4 Nuts: 2x

Comfort Option:

• Springs: ID 6mm (0.6-0.8mm wire diameter) to put over the steel rods for a self-opening effect. 

  you will need about 50mm (for the 100mm version) 65 for the 120mm and around 90mm for the 180mm version

IMPORTANT PRINTING INSTRUCTIONS This design features embedded hardware for maximum strength and a clean look.

• Use the provided 3MF file: It contains the necessary print pauses.
• Embedding the Hardware: You must insert two M8 nuts during the print process.
• Placement: One nut goes into the Moving Jaw (Dynamic Jaw) and the other goes into the Turning Knob.
• Safety: Ensure the nuts are seated fully flush before resuming the print to avoid nozzle collisions.