MARK SUTHERLAND

This #swisslathe machined part made from 4140 "pre-hard" steel alloy has high strength-to-weight ratio, making it ideal for parts requiring resistance to fatigue, impact, and wear. To mee lead-time and consistency demands, steel mills began offering machine shops this pre-hardened 4140 (typically 28-32 HRC) in bar stock form, often purchased as "4140PH". This eliminates the need for post-machining heat treat and minimizing distortion risks on tight tolerance parts. When turning or milling tight-tolerance features on 4140 steel, especially in the 28-32 HRC range, tool selection and feeds & speeds are everything. For turning, grooving and parting inserts -- I have a lot of success using Kennametal grade inserts KCU10B or KCP25B. And for drilling the Kennametal GOdrill with KC7315 or KCU25 grades perform really well and are very economical even for through coolant versions. On swiss lathes we are usually taking a finish cut in one single pass and removing a lot of material at once - not separate roughing, semi and finishing, so I am usually using a DCMT style insert. But..... on this 1/2" diameter part with tight +/ .0002" OD tolerance example, we are not having to remove a lot of material from the original bar to get to the finsh diameter so in this case for finish turning I like using a DCGT geometry insert. Why DCGT instead of DCMT? Both DCGT and DCMT inserts are 55° diamond-shaped turning inserts, but the key difference lies in the cutting edge geometry and chipbreaker design, which directly affects surface finish, tool pressure, and performance on small, tight-tolerance part. DCGT: The “G” in DCGT indicates a ground and polished edge, with a very sharp cutting edge and often a positive rake. DCMT: The “M” in DCMT refers to a molded chipbreaker with a more robust, honed edge. It’s better for general-purpose or roughing operations, where longer tool life and heavier cuts are more important than ultra-fine finishes. 👉 Bottom line: DCGT inserts cut cleaner and with less pressure, making them ideal for fine or small-diameter work (especially on Swiss-type lathes) For Turning, I usually start with 450–550 SFM (3500–4200 RPM) and a feed of 0.0015–0.0025 IPR For parting, I'm using a 1.5mm 2sided cutoff insert at around 300–400 SFM and feeding at 0.0015 IPR. For Drilling (in this case a solid GoDrill not coolant thru) I'm using 250 SFM (~4000 RPM) and feed of 0.0025 IPR. For Milling the hex flats, I'm using a 1/4" diam 4 flute variable helix solid square endmill at 350 SFM and feed 0.001 IPT per tooth. So this is about 5350 RPM and ~ 20 IPM feedrate. Fyi I'm using climb milling and finish endmilling in one single pass, but if you were needing to rough more material first then you could bump up the feedrate on those passes to about double. #manufacturing #cnc #machining #machineshop #steel

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Mold Making: Where Precision Meets Craftsmanship 🎯🛠️ Mold-making isn’t just manufacturing—it’s engineered craftsmanship. Every mold represents a balance of geometry, cooling logic, material flow, and tool life optimization. From concept to cavity, each step demands accuracy and foresight. 🔍 At WIT MOLD, we view each project as a functional sculpture—built to solve problems and drive production performance.✨ Learn more: https://witmold.com/ #MoldMaking #PrecisionMolding #ToolingDesign #EngineeringCraftsmanship #PlasticMolding #ManufacturingInsight #WITMOLD #ProcessMatters

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⚠️ Tungsten Is a Critical Mineral — and It’s About to Matter More If you use machined parts, you use tungsten — whether you realize it or not. Tungsten is the foundation of carbide tooling, and carbide tooling is the heartbeat of modern machine shops. With tungsten supply heavily influenced by global politics and trade dynamics, the ripple effect is real — and it’s reaching manufacturing fast. Because of our close partnership with Iscar and Mitsubishi, we have a front-row seat to what this kind of volatility can do: • Tool costs move • Availability tightens • Lead times stretch • Quotes become harder to lock • The cost of scrap and rework becomes more painful And here’s the part many people don’t see: This kind of material pressure is yet another force squeezing American manufacturers — already battling rising wages, higher energy costs, supply chain instability, and the constant push to do more with less. The reality is, the shop floor is absorbing cost shocks from every direction. And while the mineral markets may feel far removed, their impact shows up quickly in the form of tooling expenses, capacity, and ultimately the price and availability of machined parts. We’re staying proactive, communicating with customers early, and ensuring our tooling strategy remains strong — because reliability and precision require more than great machines… they require great planning. Quality and Precision Forged by Innovation. #Machining #Tungsten #Carbide #SupplyChain #Iscar #Mitsubishi #Manufacturing #PrecisionEngineering #AmericanManufacturing #MadeInUSA

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As CNC Machining - San Diego pointed out on my post yesterday, I forgot to include a video of the actual tool cabinet on the shop floor at Heshel Machine Co. LLC. Wanted to follow up and share it here to get your thoughts, and hopefully see how others are setting up their own systems! This setup continues to work really well for our two-person shop (one full-time, one part-time). The bin colors correspond to different subdivisions of our tool library, and the labels are designed to give just the right amount of information when you’re in the middle of a setup. (Yes I know we don't have every box filled just yet!) Each label shows: -Which subdivision of the library the tool belongs to -The tool number -A short description of the tool I also added a QR code that links directly to the manufacturer’s product page, along with a small reference image for quick visual confirmation. This level of organization has allowed us to handle a large percentage of our day-to-day setups using just two drawers, which has been a huge efficiency win. As a bonus, you can also see how we organize our ER collets! Always interested in seeing how other shops approach tool organization. #machining #cncmachining #machineshop #tooling #manufacturing #shoporganization #machinistlife #metalworking

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This *was* a 3-inch long _flat_ aluminum surface used as part of a mold tool water cooling system. *Now,* it's a 3-inch long glorious example of erosion and corrosion that's *still* part of a mold tool water cooling system. I incorrectly assumed this was a catastrophic fail. But since it still holds an O-ring against the mating interface's groove, this tool will continue to work just fine. The real problem is when the O-ring groove on the other side erodes and the mold reassembly fails to capture the seal. That ends up leading to leaks and unplanned down time. Turns out, there's a simple fix for the O-ring problem that doesn't require rebuilding the entire mold. Learning the fix took 2 minutes and was shown to me by someone with 30 years experience doing mold tool building and repair. Yes, there's a generational gap in domestic manufacturing, but if we don't take the time to learn, the knowledge, skills, and experience will be lost.

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