What inner diameter for a given bolt?
Use the bolt's nominal size plus clearance: M3 → 3.4, M4 → 4.5, M5 → 5.5, M6 → 6.6, M8 → 8.4, M10 → 10.5 mm. For a snug locating fit, subtract 0.2 mm from those and ream with the bolt.
Washer and spacer generator: exact size, printed in minutes
The hardware store never has the size you need. Set inner diameter, outer diameter and thickness — from a 0.4 mm shim to a 30 mm standoff — and print exactly the washer or spacer the assembly calls for.
- - Metric bolt cheat-sheet built into the defaults (M8 → 8.4 mm bore)
- - One model covers washers, shims, spacers and standoff tubes
- - Chamfered edges: easy insertion, no elephant-foot cleanup
- - Need a slot, square bore or shoulder? One agent edit away
Parameters you can tune
Each parameter below rebuilds real geometry on every change — this is parametric CAD, not a scaled mesh.
| Parameter | Default | Range | What it does |
|---|---|---|---|
| Inner diameter | 8.4 mm | 2 – 60 | Bolt clearance: M8 → 8.4 mm. |
| Outer diameter | 24 mm | 6 – 120 | Overall washer diameter. |
| Thickness | 3 mm | 0.4 – 30 | From shim-thin to tall spacer tube. |
| Edge chamfer | 0.4 mm | 0 – 2 | Eases insertion and kills elephant-foot. |
How it works
- 1.Open the generator — the model builds right in your browser, nothing to install.
- 2.Tune dimensions and options in the parameter panel; the geometry rebuilds live in 3D.
- 3.Export STL / STEP / 3MF for printing — or ask the AI agent for features beyond the sliders.
FAQ
Are printed washers strong enough?
Under a bolt head in static assemblies, absolutely — PETG at 100% infill handles typical clamping loads. Avoid printed washers where temperature, creep under sustained high torque, or electrical conduction matters.
How accurate is the printed thickness?
Thickness lands on layer multiples: at 0.2 mm layers a 3 mm spacer is exact. For sub-layer precision (e.g. a 1.1 mm shim), print at 0.1 mm layers or ask the agent for a stack of test thicknesses.