LVL Layup Line Optimization — Motion Control Case Study

How Applied Motion Systems redesigned the control architecture of a major engineered wood producer’s LVL layup line to dramatically increase throughput, without stopping the press

The Problem: A Line Running Blind

Laminated Veneer Lumber is one of the structural workhorses of modern mass timber construction and I-Joist manufacturing. A single LVL beam can span 120 feet, and making it requires moving thousands of veneer sheets per hour through a precisely sequenced layup process, gluing, staging, stacking, and pressing, with each sheet landing exactly where it needs to be.

The line wasn’t doing that. The control system relied on photo eyes and timers: a sheet would break a sensor beam, and some fixed interval later, a drive would be told to stop. The drive would decelerate and eventually come to rest, somewhere. Where exactly was never certain. There was no encoder feedback, no position data, and no way to know where any sheet actually was with any level of precision at any given moment.

The consequences showed up as throughput and quality. Without knowing position, the system built in conservative delays to compensate for the uncertainty. Those delays compounded across every axis on the line. Speeding up meant higher variability, which adversely affected quality. The press, the heart of the operation, running continuously, was being starved by a control system that couldn’t keep up with it.

Downtime at the press cost $50,000 per hour, and any fix would have to be made while it was running.

The Solution: Position Control and a Full Mechanical Overhaul

AMS had worked with this customer before, supporting their veneer peeling operations upstream. That history meant AMS understood how the raw material was made before it ever reached the layup line, and it gave both teams a foundation of trust to take on something harder.

The first thing AMS did was not write code. Engineers spent weeks inside the machine, cataloging what was wrong: elevator designs subject to severe wear, undersized half-roll actuators, chain systems absorbing stress they weren’t designed to carry. A mechanical upgrade proposal came before any discussion of controls: new drivetrains, counterbalanced elevators with air receivers to reduce forces and associated wear, and redesigned tipples for accuracy in sheet handling and improved throughput, all equipment designed and fabricated at AMS and shipped to the mill.

Then came the controls. The entire drive system was replaced in stages, and encoder feedback was added to every axis. For the first time, the line knew where every sheet was. The software was rewritten from the ground up to exploit that position data for a motion-centric foundation rather than a timing/sequence foundation: staging sheets accurately, minimizing dwell time, and moving material through the line as fast as the physics allowed.

A new drop-corner section was designed with linear motors to facilitate a right-angle transfer. Sheet tracking was enabled, along with laser scanning of the leading and trailing edges, to facilitate skew correction. A precision indexing system spaced sheets into fans of up to 24 pieces, timed to interleave with the fan ahead of it, like two decks of cards nesting together, building a mat of 16 to 32 plies to be positioned on the previous mat ready to enter the press.

Because the press ran continuously, every code change had to be deployed live. Small sections were inserted, tested, and pulled back out if they didn’t perform, all without breaking the continuous billet moving through the press. With $50,000 per hour on the line, there was no margin for a failed update that couldn’t be reversed cleanly.

The Results: What Changed

The line now runs at 27 feet per minute across 89 axes of coordinated control, a full 20% increase in throughput while lap to lap consistency was vastly improved. The payback period came in around four months, with the dollar figures behind that math running into the millions.

The engagement didn’t end at commissioning. The customer’s satisfaction with the project led directly to AMS being named controls partner for an ongoing I-joist line upgrade at the same facility. This downstream application uses LVL cut from the same line as the upper and lower flanges of each joist.

What Made It Different

Timers controlled the line because that’s how these lines had always been controlled. Replacing timers with position feedback sounds straightforward, but it required replacing the entire conceptual model of how the line worked, not just the hardware.

AMS also didn’t separate the mechanical problems from the controls problems. The two were intertwined, and solving one without the other would have left throughput on the table. The willingness to crawl through a machine, build a list of everything wrong, and fix it all, mechanical and electrical, hardware and software, is what made the optimization possible.

The live-deployment constraint added a discipline most integrators don’t develop: the ability to improve a running system incrementally, with real consequences for getting it wrong, and a clear plan for getting it right.

Technologies

• Encoder-based position control with motion planning replacing timer-driven logic
• Linear motors (drop-corner section) for low maintenance, high reliability sheet transfer
• Laser edge scanning and active skew correction, maintaining orthogonal sheet orientation from bin to press
• Full servo drive architecture replacing legacy drives
• Counterbalanced elevator systems with air receivers to dramatically reduce maintenance and power requirements
• Custom tipple and conveyor equipment designed and fabricated by AMS to facilitate accurate sheet placement and higher throughput
• Microwave pre-cure and rolling press integration

About Applied Motion Systems

AMS is a systems integrator and machine builder. Our work spans motion control and industrial automation across paper converting, web handling, forest products, aerospace tooling, renewable energy, and applications most companies haven’t tried before.

We start by learning the process: the machine, the material, the environment, and the constraints that actually govern how the system has to work. We design for the environment the system will actually operate in, and we think about what it looks like five years after commissioning, because that’s when building it right becomes obvious.

If you are working through a motion control or automation challenge in a demanding environment, we would welcome the opportunity to discuss it with you.