Quick Answer: Which CNC Material Is Cheapest?
Aluminum 6061-T6 is the cheapest metal for CNC machining and Delrin is the cheapest plastic. Both machine fast with low tool wear, so they cost less per part than steel, stainless or titanium. Cost is compared as a multiplier of Aluminum 6061-T6: SS 304 runs about 1.65×, Ti-6Al-4V about 3.50× and Delrin about 0.85× for the same part.
This calculator uses an Aluminum 6061-T6 baseline cost × material multiplier model to compute: cost per part, lead time, tensile strength in ksi, weight and corrosion resistance for each material. Inputs include part size, complexity and quantity, plus the materials you pick to compare.
Typical cost multipliers (vs Al 6061-T6): Delrin 0.85× | Al 6061-T6 1.00× | Al 7075-T6 1.25× | SS 304 1.65× | SS 316 1.85× | PEEK 2.80× | Ti-6Al-4V 3.50×. Tensile range Delrin 10 ksi – Ti-6Al-4V 138 ksi.
How We Calculated This
This calculator uses Aluminum 6061-T6 as the baseline material (cost factor 1.00). Every other material is priced relative to that baseline. The multipliers account for raw material cost, machining speed, and tool wear rate.
Baseline Cost
The baseline cost depends on part size, complexity, and quantity. A medium-complexity Aluminum 6061-T6 part at 10 pieces starts around $65. Small parts cost less; large parts cost more. Complexity and quantity adjust the baseline up or down.
Material Multipliers
Each material has a cost multiplier relative to Aluminum 6061-T6. For example, Stainless Steel 304 at 1.65x means a $65 aluminum part costs about $107 in stainless. Titanium Ti-6Al-4V at 3.50x makes that same part about $228. Delrin at 0.85x brings it down to about $55.
Lead Time Estimates
Lead times vary by material availability and machining difficulty. Aluminum 6061-T6 and Delrin are always in stock and machine fast. Titanium Ti-6Al-4V and PEEK may need longer because they machine slower and stock may need to be ordered.
Pro tip: If you are still in the design phase, prototype in Aluminum 6061-T6 even if the production part will be stainless or titanium. You save money on prototypes and can switch to the final material for production runs.