Use the 3D Print Tolerance & Clearance Test Generator
Generate a tolerance test plate STL with a row of numbered holes (round, square or hex) in increasing clearance plus matching pegs.
- Free to use
- No signup
- Nothing to install
- Runs in your browser
A nominal 8 mm test from 0 to 0.35 mm in 0.05 mm steps gives holes of 8.00 to 8.35 mm; on a typical 0.4 mm FDM printer hole 3 (8.10 mm) is a snug press fit and hole 5 (8.20 mm) slides freely.Open the 3D Print Tolerance & Clearance Test Generator
Illustration. Open the tool for the real thing.
What is the 3D Print Tolerance & Clearance Test Generator?
Why does an 8 mm hole print as 7.8 mm? Printers over-extrude, plastic shrinks and round holes polygon-ise, so every printer and material needs its own hole offset. This generator creates a plate with a row of holes at your nominal size plus increasing clearance (for example 0, 0.05, 0.10 … 0.35 mm), with numbers raised beside each hole and a matching plate of pegs at the nominal size.
Print it with your usual settings, try the pegs or your real bolt, magnet or shaft in each hole, and note the first one that fits the way you want. The table gives each hole's exact size. Use that clearance in every future design.
3 steps to your result
Open the tool and follow along. Nothing to install.
What you get
Bolts, nuts, magnets and rods.
Start, step and number of holes.
Raised numbers beside the holes.
Optional peg plate.
AZRS tools are free to open and use.
It opens in your browser, so there is nothing to download.
Used for
Pick one to see how it fits.
How it compares
A plain look at this tool next to the usual alternative.
| This maker tool | Desktop software | |
|---|---|---|
| Install | Nothing to install | Usually an app or program to install |
| Account | No signup | Depends on the product |
| Cost | Free to use | Free or paid, depends on the product |
| Where it runs | In your browser tab | On your computer |
Questions people ask
How much clearance do I need?
0.1–0.3 mm for most FDM fits.
Why are holes smaller than designed?
Over-extrusion and polygon approximation.
Do pegs print well?
They print standing up with a 2 mm base.
Is it free?
Yes.
How do I use the 3D Print Tolerance & Clearance Test Generator?
1. Enter the nominal size and clearance range. 2. Generate and download the plate. 3. Print with your normal settings. 4. Test fit and note the winning hole.
More free tools
Related to the 3D Print Tolerance & Clearance Test Generator.
Try the 3D Print Tolerance & Clearance Test Generator now
Generate a numbered test plate with holes of increasing clearance and matching pegs to. Free to use.
Try it free