Wood is too dried out
The compact chipper series (FM6DD & FM4DDE) are designed primarily for chipping freshly cut wood. The FM6DD has been tested thoroughly chipping freshly cut hawthorn wood (slow-grown hardwood).
We recommend that the wood is chipped no longer than three days after cutting. After this date, the wood will begin to dry out, meaning the chipper blades then struggle to dig into the wood. This produces a sawdust-like waste from the exit chute, and the chipper will struggle to self-feed.