Looking for precision stainless steel turned parts? VOLCRIX machines 303, 304, 316, 416, and 17-4PH stainless on Swiss lathes. ±0.01mm tolerance, fast turnaround.
Stainless steel is the most common material we run through our Swiss turning machines — probably 40% of our production volume. It’s versatile, corrosion-resistant, and strong, but it’s also the material that separates experienced shops from beginners. Here’s what you need to know when ordering stainless steel turned parts.
Not all stainless steels machine the same way. The grade you pick affects cost, lead time, and achievable tolerances.
303 Stainless Steel — This is the standard for automatic machining. It has added sulfur for chip-breaking, which means faster cycle times and better surface finish. If your part doesn’t need welding and isn’t in a highly corrosive environment, 303 is usually the most cost-effective choice. Surface finish easily hits Ra 0.4 μm.
304 / 304L Stainless Steel — The all-rounder. More corrosion resistant than 303, but it work-hardens faster and generates longer, stringy chips. We run it every day but it requires sharper tooling and better coolant delivery than 303. Tolerances: ±0.01mm is achievable but requires stable fixturing.
316 / 316L Stainless Steel — Marine grade. Excellent corrosion resistance, especially against chlorides and acids. 316L (low carbon) is preferred for welded assemblies. Machining is similar to 304 but tougher on tooling. Common in medical devices, marine hardware, and food processing equipment.
416 Stainless Steel — The free-machining version of 410 stainless. Magnetic, heat-treatable, and machines almost as easily as 303. Good for shafts, valves, and any part that needs wear resistance plus corrosion protection. Often replaces 303 when magnetism is required.
17-4 PH Stainless Steel — Precipitation-hardening grade. Machined in the annealed condition (soft), then heat-treated to high strength (up to 200 ksi). Common in aerospace, oil & gas, and high-stress mechanical components. Requires careful planning because the part changes dimension slightly during heat treatment.
Stainless steel moves more during machining than brass or aluminum because of the heat generated at the cutting zone. That said, on our Citizen and Tsugami Swiss machines with through-coolant tooling, we routinely hold:
The key difference with stainless is thermal management. A 0.01mm tolerance on a brass part at 9 AM is still 0.01mm at 3 PM when the coolant warms up. With stainless, thermal growth during a production run requires active compensation or tighter coolant temperature control. We monitor part dimensions at defined intervals and adjust offsets before they drift out of spec — not after.
Common Stainless Steel Turned Part Applications
Stainless steel parts can be used as-machined for most applications, but sometimes you need more:
Stainless steel machining is where experience matters most. A shop that only runs aluminum will struggle with stainless because the cutting parameters, tool selection, and coolant strategy are completely different.
We’ve been cutting stainless on Swiss machines since 1990. That means we know which insert grade to use for 304 versus 316, how to handle the stringy chips from 304 without stopping the machine, and what feeds and speeds keep the heat under control in 17-4PH.
Send us your drawing — we’ll recommend the best grade for your application, give you a firm price, and a realistic delivery date. Prototypes in 5-10 working days, production in 3-4 weeks. DDP available to US and EU addresses.
