Clinched nail (pallet)
Also called: clinch nail, clenched nail, mat nail
A clinched nail is driven all the way through the parts it joins and has its protruding tip bent over flat. Block-pallet deck mats (deckboards plus stringerboards) are commonly assembled with clinched nails.
In depth: Block pallet: construction, dimensions and uses
On a block pallet, the top deckboards and the stringerboards are often nailed together first as a flat "deck mat". The nails go right through both boards against a steel plate that bends the points over, so the joint is held by the bent tip rather than by friction.
Rules and typical values
| Item | Value |
|---|---|
| Penetration | Complete, through the whole mat (Uniform Standard, 2012) |
| Minimum length | At least 1/4 in (6 mm) longer than the stack thickness |
| Typical mat nail (vendor example) | 1-5/8 in (41 mm) smooth shank |
| Wire stiffness | Softer wire; one PDS sheet shows a mat nail at 108° MIBANT |
For two 5/8 in boards (1-1/4 in stack), the rule gives a minimum length of 1-1/2 in; a 1-5/8 in nail meets it.
Why it matters
Clinching lets thin boards be joined securely with short nails, because the bent tip cannot withdraw. Plain-shank nails work here even though they hold poorly as ordinary pallet nails. The wire has to be soft enough to bend without snapping, which is why mat nails have high MIBANT angles compared with deck nails. Poor clinching leaves points sticking out, which can tear packaging and injure handlers.
On a spec sheet
PDS lists the "Mat Assembly Method: Mat Fasteners Clinched" and gives a separate fastener column for mat nails.
Related
- GlossaryPlain shank nail (pallet)A plain shank nail has a smooth shank with no threads. It has the lowest withdrawal resistance of pallet nails, so on pallets it is mainly used where it is clinched, such as block-pallet deck mats.
- GlossaryStringerboard (block pallet)A stringerboard is a continuous board on a block pallet that runs the full pallet length between the deckboards and the blocks, tying the blocks together. EPAL 1 uses three stringerboards of 22 × 145 × 800 mm.
- GlossaryNail (pallet fastener)A nail is the standard fastener for wood pallets, driven through deckboards into stringers or blocks. Pallet nails are specified by shank type (helical, annular or plain), length, wire diameter, head diameter and bending strength.
- TypesBlock pallet: construction, dimensions and usesA block pallet is a wooden pallet whose deck sits on blocks, usually nine arranged 3 × 3, joined by stringerboards. The gaps between blocks give full 4-way entry for both forklifts and pallet jacks. EUR/EPAL, CP and the pooled 48 × 40 in pallets of CHEP and PECO are all block pallets.
- GuidesPallet nails and fasteners: types, sizes, MIBANT and nail countsMost wood pallets use threaded nails: helical (screw shank) for dense hardwoods, annular (ring shank) for softwoods. A typical deck nail is 2-1/4 in long with 0.112–0.120 in (11.5–11 gauge) wire. The Uniform Standard requires at least 2 nails per joint on boards up to 5-1/4 in wide and 3 on wider ones.
More in Fasteners
- GlossaryAnnularly threaded nail (pallet)An annularly threaded nail, or ring shank nail, has a series of rings rolled into its shank that lock into the wood fibers. It is generally recommended for low-density hardwoods and most softwoods.
- GlossaryHelically threaded nail (pallet)A helically threaded nail has spiral flutes rolled into its shank so it rotates as it is driven, which locks it into the wood. It is the most common pallet nail, recommended for medium- and high-density hardwoods.
- GlossaryMIBANT (nail bend test)MIBANT (Morgan Impact Bend Angle Nail Tester) is an impact-bend test for nail stiffness, run under ASTM F680. A weight strikes a clamped nail and the resulting bend angle is recorded; a lower angle means a stiffer, better nail.
- GlossaryNail head diameter (pallet nails)Nail head diameter is the width of a nail's head. It sets how well the nail resists pulling through the deckboard; the Uniform Standard requires the head to be at least 2.25 times the wire diameter for reusable pallets.
- GlossaryNailing pattern (pallet)A nailing pattern is the number and position of fasteners at each joint of a pallet. The Uniform Standard sets minimums by deckboard width: 2 fasteners per joint for boards up to 5-1/4 in wide and 3 for 5-1/4 to 7 in.
- GlossaryScrew (pallet fastener)A screw is a threaded fastener turned into the wood rather than driven. On pallets, deck screws, lag screws and washer-head self-drilling screws are used for heavy skids, plastic lumber pallets and designs that must be taken apart or repaired.
Last reviewed 2026-09-24. 235 words.