The short answer Plan the sequence as rough machine, heat treat, finish machine. Roughing removes bulk while the metal is soft, the treatment releases stress and moves the part, and finishing cuts the movement away. Finish before hardening and you inherit distortion: a quenched 4140 plate can move 0.1 to 0.3 mm over 300 mm. The default route: rough, treat, finish Heat treatment is a stage insi...

The short answer Drilling makes the hole, boring corrects its axis and size, and reaming finishes a drilled hole to a precise diameter. Expect IT12 to IT14 from drilling, IT7 to IT9 from boring, and IT6 to IT8 from reaming, with surface finish improving from Ra 12.5 down to 0.4 micrometres. Three jobs, three tools The three operations are separated by what each one is allowed to change. A twis...

The short answer Cut copper with a sharp, high-positive-rake tool, a feed and depth heavy enough to stay under the work-hardened skin, and flooded coolant. Never let the tool rub: a minimum depth of about 0.13 mm, feeds of 0.03 to 0.05 mm per tooth and 150 to 400 m/min keep the cut shearing cleanly. Why copper hardens under the tool Work hardening, also called strain hardening, happens when th...

The short answer A 5-axis machine moves the tool on three linear and two rotary axes, so it can cut five faces of a part in one setup. It beats 3-axis when the part needs three or more setups, tolerances of ±0.01 mm across different faces, or compound-angle geometry. What the two extra axes actually change A 3-axis vertical machining centre moves the tool along X, Y and Z, and the part sits st...

The short answer CNC drilling removes the operator from the cycle. The machine positions each hole to within 0.01 mm, changes tools in under 2.5 seconds and runs drill, countersink and tap in one program. Measured throughput is 80 to 200 holes an hour against 20 to 40 by hand, and positioning scrap falls from 3 to 5 percent to under 0.5 percent. What actually changes when the operator leaves t...

The short answer A CNC drilling service produces through and blind holes, counterbores for socket screws, countersinks for flat-head screws, spotfaces for washers, reamed bores at H7, and tapped threads in UNC, UNF and metric sizes. Twist drills reach 5 to 8 times diameter, reaming lifts the fit to 0.005 to 0.02 mm, and gun drilling reaches 100 to 150 times diameter. Every hole starts as one o...

The short answer A professional CNC milling shop works to ISO 2768-m by default, which is 0.1 mm on a 6 to 30 mm feature and 0.3 mm from 30 to 120 mm. Precision work tightens to 0.025 to 0.05 mm, a controlled shop reaches 0.005 to 0.01 mm on a callout, and surface finish runs from Ra 3.2 to 0.4. The default is a standard, not a number When a drawing does not put a tolerance on a dimension, the...

The short answer Judge a CNC milling supplier on evidence rather than on price: the registered entity and its own machine list, the tightest tolerance it holds every day with a first-article CMM report behind it, the inspection plan, and how it answers DFM questions. Ask for two past lot sizes and run a trial order before a mass-production release. Start with the entity, not the price list The...

The short answer CNC milling holds the workpiece and moves a rotating cutter along a toolpath generated from the CAD model, removing material in thin layers. Three axes cut prismatic faces, pockets and slots; a fourth adds indexing, helical and cylindrical work; five simultaneous axes cut free-form contours and undercuts in one setting. The four steps from model to finished face Milling is sub...

The short answer Five industries carry most precision CNC turning demand: automotive at 27 percent of precision machining revenue, aerospace and defence at 24 percent, medical devices at 18 percent, semiconductors and electronics at 16 percent, and industrial machinery at 15 percent. All five buy a round form that must run true at speed. Where precision turning demand actually sits Turning is ...

The short answer Custom CNC turning holds ±0.01 to 0.05 mm to standard, tightens to 0.002 to 0.005 mm on a precision lathe, and reaches 0.001 to 0.002 mm on a Swiss-type machine. Roundness runs 0.5 to 3 micrometres and surface finish reaches Ra 0.4 micrometres. Geometry, not the machine alone, sets the limit. Three tiers, and what separates them Turning capability is usually quoted as a single...

The short answer The difference is motion. CNC turning spins the workpiece against a stationary single-point tool, so it makes round, axially symmetric parts fast and concentrically. CNC milling holds the part still and rotates a multi-point cutter, so it makes flat faces, pockets and slots. Round part: turn it. Everything else: mill it. One mechanical fact explains the rest Almost every pract...

The short answer Plan on 3 to 7 working days for a prototype, 7 to 10 days for a small batch and 14 to 30 business days for production, measured from an approved drawing. Add 2 to 4 days for a specialty alloy and 2 to 5 days if the part needs finishing, then 2 to 7 days by air. A lead time is a queue, not a machining speed Buyers usually compare lead times as if they measured how fast a suppli...

The short answer Aluminium 6061 and 7075, stainless 303, 304 and 316, carbon and alloy steel, titanium Ti-6Al-4V, brass C360 and copper C110 cover most metal work; POM, nylon, PEEK and ABS cover most plastic work. Material and machinability together drive 35 to 60 percent of part cost. Machinability, not price per kilo, drives the part cost Two materials can cost the same per kilogram and prod...

The short answer Treat an OEM award as a gated programme, not a search. Sign the NDA, place a paid sample order of 5 to 20 pieces, clear first article inspection and a written quality agreement, then run a pilot lot at 10 to 30 percent of annual volume. Budget 4 to 8 weeks from first contact to a qualified supplier. An OEM award is a programme, not a search The question most buyers ask is whic...

The short answer Precision CNC machining is defined by three measurable things: tolerances of 0.025 mm or tighter against 0.1 to 0.2 mm for general work, surface finish down to Ra 0.4 micrometres, and repeatability proven by Cpk 1.33 or above. It cuts without tooling and suits almost any metal. Precision is three measurable numbers, not one "Precision machining" is a phrase that suppliers use ...

The short answer A CNC quote is six numbers, not one. Machine time carries 30 to 60 percent, material 15 to 40 percent, setup and programming 10 to 25 percent, tooling 5 to 15 percent, finishing 5 to 25 percent and inspection 5 to 10 percent. Quantity then changes the unit price more than any negotiation. A quote is six numbers, not one Buyers often treat a machined part price as a property of...

The short answer A precision CNC floor is built from six groups of machines: three-, four- and five-axis mills, turning centres and Swiss-type lathes, grinding machines, wire and sinker EDM, and inspection equipment such as CMMs. Between them they cover tolerances from 0.05 mm down to 0.002 mm on the right part. What a machine list should tell you When a buyer asks what equipment a supplier ha...

The short answer CNC machining is subtractive manufacturing in which a pre-programmed computer controls the movement of a machine tool. A CAD model is converted into toolpaths, a spindle or wire removes material to those paths, and the part is measured against the drawing. It holds 0.025 mm or better. What "computer numerical control" actually means CNC stands for computer numerical control, a...