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Nut-trap gauge: M3 5.5 / 5.7 / 5.9 AF and M4 7.0 / 7.2 / 7.4 AF
What nut-trap size does my 3D printer need for M3 and M4 nuts? · Hardware · basis: Hex traps stepped from the ISO 4032 across-flats (M3 5.5, M4 7.0) in 0.2 mm steps
Long Earth Society build part. Print these first to measure your allowances; every LES part is drawn at exact size. The engines
Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features
- sizes
- 2 in table
Notes
- Every file on this site is drawn at exact size with no printing allowance; this gauge steps through sizes around the nominal so you can measure the allowance your process needs for one fit class, then apply it only to the features each object lists under Mating features.
- The gauge is an 80 × 24 × 5 mm plate with six hex traps on 13 mm pitch: M3 at 5.5, 5.7, 5.9 AF, 2.7 deep, and M4 at 7.0, 7.2, 7.4 AF, 3.5 deep.
- Press an M3 or M4 hex nut into each trap: the trap that holds it snug, minus 5.5 or 7.0, is your nut-trap allowance.
Sizes
| trap | af_mm | depth_mm |
|---|---|---|
| M3 | 5.5 / 5.7 / 5.9 | 2.7 |
| M4 | 7.0 / 7.2 / 7.4 | 3.5 |
Mating features
Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.
| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| gauge sizes | stepped around nominal | the true pin, nut, bearing or extrusion slot being tested | designed | all |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Wikipedia | Engineering tolerance | web | CC BY-SA 4.0 (text) |
| Prusa | Knowledge base: XY size compensation | web | Prusa KB verify |
| Long Earth Society | Engine and rig builds | web, video | LES site |
Free files
★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
Plain text: sheet.txt · JSON: /api/geometry?object=nut-trap-gauge
How it fits
Connects to
Hex nuts, M2–M8M3 (5.5 AF) and M4 (7.0 AF) nuts pressed into the trapsAlso needed
Hole gauges for Ø3, Ø5 and Ø8the screw-hole allowanceYou might also need
Questions
What size nut trap for an M3 nut?
The nut is 5.5 mm across flats; print this gauge and the trap that holds it snug, minus 5.5, is your allowance.
How deep are the traps?
2.7 mm for M3 and 3.5 mm for M4.