MDF has no grain and no layers, so its edge is a uniform, friable surface that crumbles rather than chips. It is also absorbent: an unprotected edge takes water faster than the face and swells locally, which shows as a raised lip under the veneer or paint. A U channel covers the edge and keeps the band off it.
Two failures, one component
Mechanical: a band tensioned on a bare MDF edge compresses it, the edge rounds over, and the stack sits unevenly. Physical: the same edge, left open, absorbs moisture from a damp pallet or humid air.
A channel addresses both. It spreads the band load over the leg and it covers the edge line, so the edge is not the first surface to meet water.
Specification at a glance
MDF is dimensionally consistent, so the channel can be a close fit, which is what keeps it on during handling. Wall thickness follows the band, not the panel.
| MDF | Inner width | Leg | Wall |
|---|
| 12 mm | 12-13 mm | 40 mm | 3 mm |
| 18 mm | 18-19 mm | 50 mm | 3-4 mm |
| 25 mm | 25-26 mm | 50-60 mm | 4 mm |
| Edge banded 18 mm | 21 mm over the band | 50 mm | 3-4 mm |
| Calibrated 18 mm | 18-19 mm | 50 mm | 3-4 mm |
Close fit, because MDF does not forgive
A loose channel on MDF slides off and leaves the edge bare. A close fit works because MDF thickness varies little across a sheet, unlike plywood.
Where the panel is calibrated MDF, the thickness is tighter still, and a 1 mm clearance is normal. Where it is uncalibrated, measure a few points and specify the mid value.
Cutting, routing and the finished edge
MDF is often routed after delivery. The routed edge is unprotected, and that is accepted; the channel protects the edge as supplied, not the edge the customer creates.
For panels that will be edge banded, keep the channel off the band line if the band is applied before packing, or fit the channel over the band with a wider inner width. Forcing a channel over a 2 mm band creases it.
Questions buyers ask before ordering
Why a closer fit than plywood?
MDF thickness varies less, so a close channel stays on without creasing.
Will the channel stop edge swelling?
It keeps the edge off a damp surface and away from the band. It is not a moisture barrier.
Can it fit over an edge band?
Yes, with the inner width increased by the band thickness. Forcing it over a band creases the fold.
What wall for a banded stack?
3-4 mm with a 50 mm leg. The band load is spread along the leg.
Do you cut to the panel length?
Yes, to the millimetre, up to 6,000 mm.
For a quotation, post the product dimensions, load and destination port to mona@hengnicepacking.com.
