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Honeycomb Bed for Diode Lasers: Do You Need One, and How to Set It Up

For cutting: yes, you need a honeycomb bed. When your beam exits through the bottom of the material, smoke and burning debris need somewhere to go — the 7.5 mm hexagonal gaps let them fall through. Without that gap, smoke recirculates under the material and scorches the underside. For surface engraving on flat, thick stock, a honeycomb bed is a nice upgrade but not essential. Last verified: 2026-07-07 — lasertinkerer.com

What does a honeycomb bed actually do for a diode laser?

A honeycomb bed is a flat panel made from stainless or carbon steel with a hexagonal grid of cells running through it. It sits on your machine bed and lifts the workpiece 20–22 mm above the surface. Three things happen when you add one:

1. Through-cuts get a smoke exit. When you cut all the way through wood or acrylic, combustion gases, char dust, and fine debris are generated beneath the material. Without a gap, all of that stays trapped under the workpiece and burns it from below — the result is a dark, scorched underside and sometimes re-ignition of debris. The honeycomb's open cells give that smoke somewhere to go.

2. Air assist can work on both sides of the cut. If your machine has air assist, the pressurised air stream from above needs somewhere to push the smoke. With the material on a solid bed, the air hits the material underside and bounces back. With a honeycomb, air and smoke travel downward through the cells and exit below. This is why air assist roughly doubles cut depth per pass when used with a honeycomb bed.

3. Back-reflection is scattered, not focused. When the beam exits through the bottom of the material, whatever surface is below it will reflect some of the laser energy upward. A solid steel bed reflects that energy back in a concentrated point — scorching the material underside. The honeycomb's cells scatter any reflected beam in multiple directions, reducing the intensity of what hits the material from below. Smaller cells (the optimal 7.5 mm hexagonal size) give less exposed flat surface than larger cells.

For engraving — where the beam doesn't exit through the material — these effects are less important. The main benefit for engraving is that thin or warped sheets lie flatter against the honeycomb surface than against a flat bed, and you can use honeycomb pins to hold them without tape marks.

How do I adjust focus height when I add a honeycomb bed?

This is the step most people skip, and it causes blurry cuts. A honeycomb bed raises the material surface by its own height — typically 20–22 mm. Your laser now has to travel 20–22 mm less distance to reach the material. If you don't compensate, the beam arrives out of focus and the cut is weak and wide.

The rule: always focus on the top surface of your material, not the top of the honeycomb.

How you compensate depends on your machine type:

A quick check: engrave a single thin line on a scrap of your material. If the line is crisp and narrow, focus is correct. If it's wide and fuzzy, you're out of focus — adjust the gantry height and try again.

What size honeycomb bed do I need for my laser?

You want a bed that fits inside your machine's work area — slightly smaller than the full cutting envelope, so it doesn't obstruct travel. What matters is the usable work area, not the machine's outer dimensions.

Before buying, measure your machine's practical cutting area — this is smaller than the work area spec because gantry overhang, cable chains, and limit switches eat into the edges. A honeycomb bed 10–20 mm shorter on each side than your quoted work area is typically safe.

Two smaller beds can be tiled together for occasional large-piece work, which gives you more flexibility than one fixed large bed.

Work surface types compared: honeycomb, slat, knife-edge, and bare bed

The honeycomb bed wins on versatility. For pure engraving on thick, rigid pieces, the bare machine bed is fine. For anything involving a through-cut, a honeycomb or slat bed is the minimum you need.

How do I use honeycomb pins to hold material flat?

Honeycomb pins — sometimes called "laser pins" or "hold-down pins" — are small pegs with a pointed or hooked end that slot into the cell gaps of the honeycomb. You push them in around the edges of your material to hold it against the bed.

They're especially useful for:

• Thin sheets that warp during cutting (thin plywood, cardstock) — pressing them flat at the edges prevents the beam from hitting an angled surface mid-cut
• Repeat work where you need the material in the same position each time — pins give a repeatable mechanical register
• Delicate materials where tape would leave adhesive residue (fabric, vellum, suede)

Most branded honeycomb beds come with a set of pins. Generic sets cost around $5–$10 for 20 pins. Magnets also work well on a steel honeycomb — they hold material from the sides without occupying cell space.

For very thin or flexible materials (fabric, felt, thin paper), combine pins with a light spritz of repositionable adhesive spray on the honeycomb surface — this stops the material from lifting between pin points.

Can I make a DIY alternative to a honeycomb bed?

Yes, and it can work just as well for cutting. The goal is simply to lift the material with minimal contact surface and leave gaps for smoke to escape. Several approaches work:

Aluminum venetian blind strips are the classic free alternative. Lay them across the machine bed at 8–10 mm spacing, running parallel to the X-axis. The open gaps let smoke and debris fall through. They can warp at high temperatures over time but last a long time for diode-laser temperatures. Cost: essentially free if you have an old set of blinds.

Nail bed: Drive finishing nails in a grid pattern (approximately 25–30 mm spacing) into a piece of MDF. The material rests on the nail heads at a uniform height. Works well for smaller pieces. The nails will discolour over time but not fail. The low contact area means the nail heads don't show on the underside.

Brick spacers or ceramic tiles: Two parallel rows of bricks or thick ceramic tiles, one on each side of the cut line. Works for straight-cut pieces. Not practical for arbitrary-shape cutting.

What you lose with any DIY option: the honeycomb pin work-holding system. DIY beds need tape, clamps, or weights instead. For quick jobs this is fine; for production volume, pins are faster.

How do I clean a honeycomb laser bed?

Char, resin, and cut debris accumulate in the cells over time. A clogged honeycomb reduces airflow and starts reflecting more energy upward. Clean it regularly — every few sessions for heavy cutting work.

• Loose debris: tap the bed edge-on over a bin. Small bits fall out of the cells on their own.
• Char dust: compressed air blown from above forces debris downward through the cells — do this outside or near your fume extractor inlet
• Resin / sticky residue: apply isopropyl alcohol (IPA, 90%+) and let it soak for a few minutes, then scrub with an old toothbrush and rinse with more IPA. Avoid water — steel honeycomb will rust if it gets wet and stays wet
• Heavy char build-up: a 30-minute soak in a shallow tray of IPA dissolves most resin accumulations

A well-maintained honeycomb bed lasts for years. Let it air-dry completely before using it again — a damp bed can cause flash-vaporisation if the laser passes over a wet cell surface.

When is a honeycomb bed not the right choice?

A few situations where a honeycomb bed actually causes problems:

• Very thin, flexible material (paper, fabric): thin stock can sag into the cells during engraving and create an uneven surface. Use a solid flat substrate underneath or add more pins. A cutting mat works better for very light engraving on paper.
• Round or irregular objects: a honeycomb bed is designed for flat sheet material. Tumblers, bottles, or odd-shaped pieces need a rotary attachment or custom jig, not a honeycomb bed.
• Thick tiles or heavy stone slabs: ceramic tile or slate can sit flat on the machine bed for engraving — they won't warp and you're not cutting through them. The honeycomb adds unnecessary height that your gantry may not accommodate.

Frequently asked questions

Where to find a honeycomb bed

Look for beds sized for your machine and made from steel (not thin aluminium foil — these warp and sag). The cell size should be 6–8 mm; beds outside this range are less effective. Most come with a set of pins included.