How to reduce wane waste on unedged boards: practical steps before the multi-rip

Wane is one of the main reasons yield on unedged-board lines is unstable. The issue is rarely “the multi-rip is bad”. More often the issue is that boards enter the saw in random offset and angle, so even a good rip pattern is applied inconsistently.

Below are practical steps that typically work on real lines, from the simplest to the highest-impact.

1) Why wane waste happens (in practice)

On unedged boards, the infeed geometry matters:

• wane is not symmetric (one edge may be much worse),
• board width varies along the length,
• boards are not repeatable and may be warped.

If you add random offset and skew, the same saw spacing will “eat” the board on the wrong side and waste grows fast.

2) Quick fixes you can do without investment

Define width sets per shift (plus a fallback)

Example: prioritize 100/120/150, fallback 90/140 depending on orders. The goal is to remove ad‑hoc decisions and make the logic repeatable.

Split material into 2–3 groups

Minimum that makes sense:

• stable/regular boards,
• difficult boards (warp, heavy wane, variable width),
• (optional) shorts or special thickness runs.

This prevents forcing one pattern onto everything.

Keep a consistent infeed reference

Many mills lose yield because boards are “eyeballed” left one time and right the next. That inconsistency directly increases wane waste.

3) The biggest lever: stabilize offset and angle before the multi-rip

If boards enter:

• shifted by a few millimeters,
• or even slightly skewed,

wane waste increases because the saws hit the wrong edge. This is why many mills add automatic board positioning before the multi-rip:

• detect board position + angle,
• compute best placement for target widths and fixed saw spacing,
• position the board so the cut plan is applied consistently.

See how it works: /blog/board-centering-before-multi-rip-saw/.

4) How to verify if wane is your biggest loss (simple)

Pick 1–2 hours of production and track:

• how many boards need rework/trim due to wane,
• the average width “given away” to edge waste.

Convert it to volume similarly to a simple loss model: Loss m³ ≈ (width loss [m]) × (thickness [m]) × (length [m]) × (board count)

If you need a consistent yield measurement setup first: /blog/how-to-calculate-sawmill-yield/.

5) Checklist: when automation makes the most sense

Answer yes/no:

• Do you run a lot of unedged boards (wane is frequent)?
• Do operators regularly “nudge” boards by hand at infeed?
• Is wane waste inconsistent by shift/operator?
• Do you run fixed saw spacing and want more yield without replacing the saw?

If you have 3× yes, there’s usually real yield to recover by stabilizing infeed reference.

Tell us your infeed layout and product targets and we’ll outline the best retrofit mode: /contact/.