Feeder Guide

Feed accuracy is not a single number from a specification sheet. It is a budget shared by servo positioning, roll slip, loop and back tension, lateral position and pilot release timing. This guide breaks down the error sources by typical contribution and cost of reduction, explains what the servo axis can and cannot control, and sets out the verification tests that predict line behaviour.

Slip that starts in the last third of every coil is a load problem rather than a wear problem. Two mechanisms raise the load as the coil pays down, four causes are separated by one speed test, and five fixes that hold.

A four-input calculation that any engineer can run in ten minutes, worked through on a 2.0 mm strip. It also shows the point where a larger motor stops buying anything, because the limit has moved to grip force rather than torque.

Why an over-tight roll gap degrades accuracy instead of improving it: the four signs of over-clamping, gap multipliers by material and thickness, a five-minute verification at the machine, and three problems that only look like gap faults.

A field diagnosis of strip buckling between the feed rolls: why roll pressure, gap parallelism, back tension, material thickness and motion profile each contribute, and a six-step sequence that isolates the real cause.

How to pick a feed roll coating from the strip you actually run: the four coating families compared, why grip and wear resistance pull against each other, and the six signs that the coating has already failed.

How to separate true encoder drift from offset error and random scatter, the six causes ranked by how often they turn up, and a five-step isolation sequence that fits inside one shift.

A six-step setup sequence for thin-gauge strip on an NC servo feeder: roll pressure first, then motion profile, leveler gap, strip support, lubrication and verification.

Pilot release timing is the least visible setting on an NC servo feeder and one of the most consequential. This article explains the crank angle window, how early and late release differ in the damage they cause, and the controller procedure for setting both angles.

An NC servo feeder's usable speed depends on feed length, strip gauge and press SPM — accuracy is quoted at a speed, not in a vacuum. How to read speed ratings and validate them.

How to set NC servo feeder roll pressure: the grip required for accurate feed, the signs of too much or too little pressure, and how to adjust for material.

How to set the feed length on an NC servo feeder for a new progressive die: reading the die pitch, entering the value, verifying the pilot, and adjusting for accuracy.

How an NC servo feeder converts feed length into motor pulses: encoder resolution, gear ratio, roll diameter, electronic gearing, and why calibration matters.

Why oily strip makes an NC servo feeder slip and lose pitch accuracy, plus practical fixes: roll pressure, wipers, roll coating, tension, and material condition control.