TL;DR

Feed roll slipping in the edger causes boards to stall or skew, reducing cut accuracy. Clean the rollers, check nip pressure, and inspect the drive for wear.

What you might see

boards stalling at edger entry
boards skewing in the edger causing off-dimension cuts
drive motor current spiking without board throughput
roller surface glazed or resin-coated

Likely causes

Tap to mark as ruled out

Rubber roller surface glazed from resin and pitch accumulation
Feed nip pressure too low for the lumber thickness or species
Drive chain or sprocket worn causing intermittent torque loss
Roller rubber worn below the minimum grip depth

Required tools

Rubber cleaning solvent
Drive chain tension gauge
LOTO kit

Safety first

Lock out the edger drive before reaching into the feed roll area.
Sawdust accumulation near drive components is a fire hazard. Clean before starting any maintenance.

Procedure

7 steps · ~45 min

1
Lock out the edger drive before any inspection or cleaning of feed rolls.
Warning: Feed rolls create a nip point hazard. Lock out before reaching into the feed path.
2
Inspect all rubber roller surfaces for glazing, hardening, or resin buildup. Glazed rollers have a shiny, smooth appearance.[1]
3
Clean rubber rollers with a rubber cleaning solvent appropriate for the rubber compound. Allow rollers to dry fully before testing grip.
4
Check the nip pressure setting against the species and thickness range in the machine specification. Adjust if required.[1]
5
Inspect the feed drive chain or belt for stretch and sprocket for worn teeth. Slack or worn drive reduces torque at the rollers under load.
6
Replace worn drive components and adjust tension to specification.
7
Run a test board through at production speed. Confirm straight feed and consistent throughput before resuming production.

Sources

USNR USNR MyEdger / Trimmer Edger / Trimmer general technical documentation, USNR
Sawmill edger feed roll maintenance and drive system inspection, general sawmill practice (general)

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