Leader Pins
Leader pins keep the two halves of a die set or mould base aligned through every stroke. Alignment accuracy here protects punches, cavities and product quality.
What are leader pins?
A leader pin (guide pillar) is a hardened, precision-ground pin fixed in one half of a die set that runs in a matching guide bush in the other half. Together they maintain punch-to-die alignment during operation and protect the tool during handling and setting.
Typical materials
Hardened SUJ2 bearing steel, ground and lapped; used with plain bronze/steel bushes or ball cages depending on speed and precision.
Types of leader pins
Straight leader pins
Plain ground pillar pressed into the die base — the standard form.
Shouldered leader pins
Stepped seat gives positive axial location and easier fitting.
Demountable types
Removable pins simplify maintenance on larger die sets.
Ball-cage guide sets
Pillar running in a ball cage and bush for low-friction, high-precision guiding.
How to select leader pins
- Pin diameter and length for the die set size and stroke.
- Plain bush or ball-cage guiding by speed and precision requirement.
- Straight or shouldered mounting to suit the plate design.
- Matched pin + bush pairs for correct running clearance.
Not sure? Send what you have — a part number, drawing or photo — and our engineering team will confirm the selection.
Frequently asked questions
- What is the difference between plain and ball-cage guide pillars?
- Plain pillars slide directly in a bush — simple and rigid. Ball-cage sets run on recirculating balls, giving lower friction and very high alignment accuracy for fast or precision tools.
- Are leader pins supplied with bushes?
- Pins and bushes are made as matched pairs. Tell us the die set details and we will quote the correct pin-and-bush combination.
Related components
Guide Pins & Guide Bushes
Guide pins and bushes align mould halves at every close. They are the first components to feel misalignment — and the cheapest place to fix it.
Ejector Pins
Ejector pins push the finished part off the core when a plastic mould or die opens. They cycle millions of times against heat and friction, so material, hardness and fit decide tool life.
Locating Pins
Locating pins fix a workpiece in a repeatable position on a jig or fixture. The round-plus-diamond pair is the standard method of constraining a part without over-constraint.
Need leader pins?
Tell us the specification, quantity and application — or just send the drawing.