What tolerance should I use for modular connectors?

Start with 0.2mm total clearance per side for a snug fit on a well-calibrated printer. If parts are too tight, increase by 0.05mm increments. Most FDM printers have dimensional accuracy of 0.1-0.2mm.

Which connector type is strongest for 3D prints?

Dovetail joints are the strongest for pulling apart as they mechanically lock. Slot connectors are good for sliding assemblies. Pin connectors work well for rotational joints. Clip connectors are convenient but can fatigue over time.

How do I account for different printers?

Print a tolerance test piece first. Most slicers and printer profiles have slightly different dimensional accuracy. Test with a simple slot and tab, then adjust the clearance value in this calculator.

What minimum wall thickness should surround a connector?

At least 3 nozzle widths (1.2mm for a 0.4mm nozzle) around any connector feature. Thinner walls may crack under assembly force or during use. For load-bearing connectors, use 4-5 nozzle widths.

Should I print connectors in a specific orientation?

Yes. Print so that assembly forces are perpendicular to layer lines, not parallel. Layers can delaminate under force, so orient the strongest axis along the load direction.

3DPrintCalcs

Modular Design Calculator — Connector Dimensions

Calculate connector dimensions and tolerances for modular printed assemblies.

Nominal Connector Size

Width of the tab/slot

Nozzle Diameter

Connector Type

Fit Type

Printer Tolerance

Your printer's typical dimensional error

How We Calculate This

Connector Dimension Formulas

Clearance = Base fit clearance + Printer tolerance
Female dimension = Male dimension + 2 x Clearance
Connector depth = Nominal size x Depth multiplier (varies by type)
Min wall = Nozzle diameter x 3

The male (tab) part keeps the nominal dimension, while the female (slot) part is enlarged by the clearance on each side. This ensures consistent fit regardless of the connector size.

Frequently Asked Questions

Related Calculators

Text Emboss Calculator

Calculate minimum text size and depth for readable embossed or engraved text.

Lithophane Calculator

Calculate optimal thickness range and dimensions for photo lithophanes.

Vase Mode Calculator

Calculate wall thickness and print time for spiral vase mode prints.

Tessellation Calculator

Calculate tile dimensions and counts for tessellating surface patterns.

Pattern Repeat Calculator

Work out pattern spacing and repeat counts for decorative surfaces.

Last updated: February 2026

All calculations are estimates. Always verify settings with test prints before committing to final prints.