By Phil Huang, Elite Mold Tech. Updated November 1, 2026.<\/p>\n
Good aluminum CNC design guidelines come down to a few habits: keep walls thick enough, add radii to inside corners, limit pocket and hole depth, and tighten tolerances only where parts mate. Follow them and your part costs less, ships faster, and passes inspection. This guide gives the rules that matter most, with Elite Mold Tech capability numbers where we have them.<\/p>\n
Use the rules as a starting point. Send your file before you order, and our engineers will flag any feature that adds cost or risk.<\/p>\n
An easy part uses simple shapes, generous radii, moderate depths, and tolerances set by function. The cutter reaches every feature without special tools, and the part is held firmly while it is cut. Parts like this cut fast, hold their size, and cost less.<\/p>\n
Aluminum helps. It cuts cleanly and holds tight limits, which is why aluminum CNC machining is a popular choice for prototypes and production. Our aluminum CNC machining<\/a> \u00a0service covers ten grades, and the rules below apply to all of them.<\/p>\n Design for the tool, not only for the shape you see on screen. A round cutter cannot make a sharp inside corner, and a long thin cutter bends under load. Every rule below follows from those two facts.<\/p>\n Our minimum wall thickness for aluminum is 0.75 mm (Elite Mold Tech capability table, 2026). Thinner walls flex under the cutter, vibrate, and leave a rough surface. For tall or long walls, go thicker, and add ribs for stiffness instead of making the whole wall heavy.<\/p>\n A wall that is thin and tall is the hardest case. The taller the wall, the more it flexes at the top. As a rule of thumb, increase thickness as height increases, and ask us to review any wall that is thin relative to its height.<\/p>\n Add a radius to every inside corner, and make it larger than the cutter radius. Cutters are round, so a sharp inside corner needs a second, smaller tool or a special process. A radius lets one tool cut the whole pocket in a single pass.<\/p>\n If a mating part needs a sharp corner, use a relief cut in the corner, or round the mating part instead.<\/p>\n Keep standard drilled holes to a depth of about four times the diameter, and ask us before going much deeper. Deeper holes need special drills and slower cycles. Typical hole tolerance is \u00b10.002 in (\u00b10.05 mm) at our shop (Elite Mold Tech, 2026).<\/p>\n For critical bores, mark the tolerance on the drawing and tell us if the fit is a press, slip, or running fit.<\/p>\n Use standard thread sizes, and keep thread depth moderate. A thread depth of about two to three times the diameter is enough for most aluminum parts, because deeper threads add little holding strength. In soft aluminum, consider a thread insert for parts that are assembled and disassembled many times.<\/p>\n Set tolerances by function. Our standard is \u00b10.005 in (\u00b10.127 mm), and we hold \u00b10.001 in (\u00b10.025 mm) on critical features when you send a 2D drawing with GD&T (Elite Mold Tech capability table, 2026). Tight limits on non-critical faces only add cost.<\/p>\n\u00bfCu\u00e1l es el espesor m\u00ednimo de la pared del aluminio?<\/h2>\n
How should you design inside corners and pockets?<\/h2>\n
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How deep can you make holes?<\/h2>\n
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What are the best practices for threads?<\/h2>\n
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How do you set tolerances on aluminum parts?<\/h2>\n