Poker Chip Tray Aluminum CNC: How the Part Actually Gets Made

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  Key takeaways
• 2
  What makes a poker chip tray hard to machine
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  Why 6061-T6 is the default for aluminum chip trays
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  Pocket diameter, depth and spacing: the numbers that matter
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  3-axis, 4-axis or 5-axis: picking the right setup
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  Anodizing, blasting and engraving on a machined tray
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  From one prototype to a 10,000-part run
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  How we run a poker chip tray aluminum CNC job
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  Feature tolerances and what they cost
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  Machining route by tray geometry

A poker chip tray aluminum CNC part is mostly a rectangular plate with a grid of round pockets. That description hides the difficulty. Every pocket has to be round, at the right depth, and at the same center distance as its neighbors. If one pocket runs 0.1 mm deeper than the rest, the chip sits low and the tray looks wrong in a rack.

Standard casino chips run about 39–43 mm in diameter and 3.0–3.5 mm thick. So a 100-chip tray is a plate with roughly 100 pockets about 40 mm across and 8–12 mm deep. That is a lot of material removed from a solid billet. On a 400 × 200 × 20 mm plate, you may cut away more than half the volume.

Deep pockets in soft aluminum are easy to cut. Holding the floor flat is not. As the tool spirals down and out, the floor deflects, the wall rubs, and chips pack into the corner radius. The result is a pocket that measures fine at the top and tapers at the bottom.

So the real work is not the cutting. It is deciding the pocket geometry, the toolpath, and the order of operations so that all pockets behave the same way. Get that right and the tray looks and feels consistent, which is what a customer notices first.

Aluminum is chosen for trays for three practical reasons: it machines fast, it anodizes into a wide range of colors, and it is light enough that a full 500-chip case stays portable. The grade matters more than the fact that it is aluminum.

6061-T6 is the usual answer. It has enough strength for a tray wall 3–4 mm thick, it takes anodizing evenly, and it holds a good surface finish without tearing. It is also the most available grade, which keeps lead time short. We machine 6061 and 6061-T6 most often for this kind of part.

7075 is stronger and harder. That strength buys nothing in a tray that sits on a table. It also anodizes to a slightly different color tone and is harder on small end mills, so pocket floors show tool marks sooner. Use it only if the tray is part of a structural assembly or a hard-use case.

5052 and 5083 are fine for the tray body if you are forming sheet rather than machining from billet. 6082 and 6063 are common in Europe and behave close to 6061. Where a heavy chip tray or a die-cast version makes sense, ADC12 handles that path.

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  6061-T6Standard choice. Good finish, even anodizing, short lead time.
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  7075-T6Harder and stronger. Use only when the tray carries load.
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  5052 / 5083Better for formed sheet bodies than for billet pockets.
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  ADC12Die-cast route for high-volume trays with relaxed tolerance.

A chip should drop in and lift out without sticking. That means the pocket needs a small clearance around the chip, not an interference fit. On a 39 mm chip, a pocket diameter of 39.5–40.0 mm is a working range. Too tight and the chip jams when the felt is new. Too loose and the chips rattle when the tray moves.

Pocket depth is the second control. A 3.2 mm chip in a 10 mm pocket sits below the rim and is easy to pinch. A 3.2 mm chip in an 8 mm pocket sits proud and can be swept off the table. Depth tolerance of ±0.1 mm across the whole tray keeps the stack level when trays are nested.

Center-to-center spacing sets how the tray reads at a glance. A 42 mm pitch on 40 mm pockets leaves a 2 mm rib. A 44 mm pitch leaves 4 mm. Narrow ribs look clean but deflect during machining, so they need light finishing passes. Wide ribs are stronger and cheaper to cut.

The tray outline and mounting holes are usually the tightest features: ±0.05 mm on bolt patterns, and ±0.005 mm is available where a tray drops into a machined case. Tell us which features are functional and which are cosmetic. That single distinction changes the process plan.

A flat tray with a grid of round pockets is a 3-axis job. Face the top, rough the pockets, finish the walls and floors, then flip and face the bottom. On a 27-machine 3-axis fleet, this is the cheapest path and it holds ±0.05 mm all day. Use it for single-sided trays up to about 750 × 1,150 × 550 mm of travel.

The 4-axis route earns its place when the tray has pockets on the long side, a radiused rim, or a chamfer that runs the full perimeter. Indexing the part lets one setup cut the top and a side feature without a second vise position. That removes a re-clamp, which removes a source of position error.

5-axis comes in when the tray has a contoured top, angled chip wells, or a curved outer profile. Instead of standing the part up in a tilted vise, the tool reaches the surface at a consistent angle. Pocket floors come out flatter and rib walls come out squarer. With 16 simultaneous 5-axis centers, this is a normal setup for us, not a specialty.

The rule is simple. If the geometry can be reached from one direction, 3-axis is enough. If it needs a second angle, price the 4-axis setup. If the surface is curved in two directions, 5-axis saves hand work and blending later.

Anodizing is the finish most trays get. Type II builds roughly 5–25 μm per surface and gives clear, black, and colored results. Type III hardcoat builds more, usually 25–50 μm, and is harder and more wear resistant. Both grow the part slightly, so a pocket machined to 39.8 mm can close up after coating.

The fix is to plan for it. If the pocket must clear a 39 mm chip after Type II anodizing, cut the pocket 0.02–0.05 mm oversize. If the tray will be hardcoated, add more. Tell the machinist the finish before the toolpath is written, not after.

Bead blasting before anodizing produces a matte, low-glare surface that hides fingerprints. Brushing gives a directional grain and is usually reserved for the rim or the outer wall. Polishing to a mirror is possible but shows every handling mark, so it is rare on a working tray.

Engraving and laser marking go on last, or before anodizing if the mark should be the base aluminum color. Minimum character height is 1.5 mm for a clean laser mark. Deeper engraved logos survive blasting and coating better than a shallow laser pass.

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  Type II anodizing5–25 μm build. Color range is wide. Add 0.02–0.05 mm to pockets.
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  Type III hardcoat25–50 μm build. Harder surface, more dimensional shift.
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  Bead blastingMatte texture. Hides small tool marks and fingerprints.
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  Laser markingMinimum 1.5 mm character height for legibility.

The first tray is usually a prototype. One part, one setup, and a lot of questions answered. We run that without a minimum order quantity, so a single tray goes through the same inspection as a production batch. It is the cheapest way to find out whether the pocket fit feels right in the hand.

At low volume, a soft jaw or a machined pocket in a fixture plate holds the part. At higher volume, a dedicated fixture pays for itself. A plate with locating pins and a cam clamp loads in seconds, repeats within 0.02 mm, and lets one operator run two machines. That is where the cost per part drops.

Tooling strategy follows the same logic. On prototypes, one 6 mm end mill can rough and finish a pocket. On production, a rougher clears the bulk and a smaller finisher handles the corner radius. Tool changes cost cycle time but save floor flatness, so the trade is worth it once pockets get deeper than about 10 mm.

In-process inspection catches drift before it becomes scrap. Checking the first pocket, the middle pocket, and the last pocket on each tray shows whether the tool is wearing or the part is moving. Final inspection before shipment covers every part, with reports available on request.