CNCs execute commands sequentially. When the cycle start button is pressed, the control will execute the program from start to finish, block by block. Most controllers allow the operator to determine the point from which a CNC will begin executing the program. If the program cursor is placed on the program’s first command, the CNC will begin executing from the beginning. If the operator places the cursor on the command that begins the third cutting tool, the CNC will start at the third tool.

Once the cycle start button is pressed, the CNC will continue executing program commands until it is told to stop. Commands that will cause the CNC to stop executing include M01 (optional stop), M00 (program stop) and M30 (end of program command). When stopped by M01 or M00, pressing the cycle start button will cause the CNC to continue executing from where it stopped. When the program ending command is executed, the CNC will stop and also return to the program’s beginning. When the cycle start button is eventually pressed again, the CNC will begin executing from the program’s first command.

If your CNCs behave in this manner, there are some helpful things you can include in your CNC programs after the program’s ending word (M30). In normal operation, the CNC will not “see” or execute these commands. If the special sequence commands are to be executed, the operator will have to scan to them, just as they would when rerunning a cutting tool. These commands are ones that you might want your operators to execute occasionally but not for every cycle. 

Consider the examples below. With a little thought, you can probably come up with others that are more appropriate to your specific needs.

It may be important for the machine’s axes to be in a specific location when the program is run. Maybe obstructions (like the tailstock) could cause interference if the axes are not appropriately pre-positioned. Consider these commands:

O0001 (program number)

N005 T0101 (index to station one)

N010 G96 S500 M03 (start the spindle)

N015 G00 X1.7 Z0.1 M08 (move to first X/Z position, start coolant)

. (begin commands for the rest of the program)

N550 G00 Z0.1 M09 (retract last tool, stop coolant)

N555 X8.0 Z5.0 (move to safe index position)

N560 M30 (end of program command)

N999 (beginning of special program sequence)

G28 U0 (move to X-axis reference position)

G28 W0 (move to Z-axis reference position)

G00 W-12.0 (move Z axis to safe starting position)

M30 (returns execution to the program’s beginning)

Note that a parameter setting controls when the CNC stops loading a program. For this program to be loaded in its entirety, the parameter must be set to the end-of-file delimiter (%). Otherwise, the CNC will stop reading when the first M30 is read, and the N999 sequence will not be loaded.

The commands after the first M30 will not be executed during normal operation. Whenever the operator needs to send the machine to the safe starting position (after setup, beginning of shift, after stopping the program, etc.), they scan to sequence number N999 and run the program from there. When the CNC reaches the second M30, it will stop the program’s execution and return to the program’s first command. The N999 special sequence will not be executed again unless the operator scans to it.

If you elect to use this technique, use an easy-to-remember sequence number (like N999) as the special sequence starting command. Do so for every program in which you incorporate this technique so that operators can always scan to the same sequence number.

If you make qualified setups on machining centers, you probably include a series of G10 commands that enter values into related fixture offsets. These commands are probably being executed every time the program is run. If the operator needs to tweak a fixture offset value — and if they do so in the fixture offset itself — the adjustment will be overwritten the next time the program is run. This issue can be overcome by including the G10 commands in the special N999 VBMT Insert sequence. The operator will scan to and execute the special sequence once during setup.

The special sequence may be able to provide some help for setup people. Maybe a fixture hole or pin must be indicated to assign the program’s origin for a machining center program. You can include a rough positioning movement to the hole’s or pin’s X/Y center in the special sequence, like so:

N550 M30 (end of machining program)

N999 G91 G28 Z0 (send the Z axis to its reference position)

G28 X0 Y0 (send the X/Y axes to their reference positions)

G00 X-10.0376 Y-7.9037 (move over the hole/Carbide Milling inserts pin in XY)

M30 (end of special sequence)

Using custom macro techniques, you can allow an operator to perform certain job-specific calculations, like determining offset adjustment amount for sizing a thread after a measurement has been taken over pins.

If workpiece rework is sometimes required after machining, include the related commands in a special N999 sequence. For instance, maybe the operator must polish or sand a turned diameter. The commands to start and stop the spindle could be included in the special sequence.

The Carbide Inserts Website: https://www.aliexpress.com/item/1005005979895118.html

The Giddings & Lewis V series available from Fives Machining Systems is a line of vertical turning centers designed for shops that need a multi-purpose lathe capable of handling a range of parts such as pumps, valves, gears, bearings, compressors, wheel hubs, jet engine housings and more. The series features a solid cast iron base construction, optional live spindle attachments and a C-axis table.

All six cemented carbide inserts models, with table sizes ranging from 800 to 2,500 mm, feature a hydrostatic ram that adds rigidity, enabling heavy cutting with less friction for improved part finish. The hydrostatic, wear-free guides require less maintenance, according to the company. The infinitely adjustable cross rail serves as a programmable positioning axis, able to handle a range of parts and to minimize ram extension. Dual-scale feedback delivers precision and ensures parallelism, while the hydraulic cylinder elevation adds a secure 1,000 kN (225,000 lbs) of mechanical clamping force per side.

The VLock tooling system provides a stiff interface for modular tooling adapters, long cutting tools, and an optional heavy-duty, right-angle bar peeling inserts milling attachment. According to the supplier, modular turning tools offer greater taper stiffness at loads ranging to 1,800 Nm. These machines provide through-tool coolant and 8-bar (116-psi) flood coolant in addition to a 12-position tool-storage disk, as well as options for high-pressure coolant and an 18-tool storage disk. Other options include tool and part probes to increase utilization and ensure part quality.

The Carbide Inserts Website: https://www.aliexpress.com/item/1005005954890402.html

Walter Surface Technologies has released its Zip shoulder milling cutters Titan and Chopcut Titan abrasive cutting disks designed for cutting titanium and brass with exceptional efficiency. Both the Zip Titan and Chopcut Titan are made with a silicon-carbide-based formulation to prevent the materials being cut from overheating, the company says; keeping the metal cooler helps to preserve the mechanical properties and surface integrity of titanium and brass.

The products are both said to offer a longer lifespan than other, similar disks. The company explains that the efficient cutting action of the wheel prevents it from overheating, which is the number one risk for cutoff wheels. These disks are intended to provide more cuts per wheel as well as faster and freer cuts, increasing job productivity and lowering costs.

The Zip Titan is part of the company’s Zip family of cutting wheel products gravity turning inserts designed for cost savings through longer tool life and more cuts per wheel. The Chopcut Titan belongs to the Chopcut family of products, designed for performance cutting on portable chop saws.

The Carbide Inserts Website: https://www.aliexpress.com/item/1005005979934200.html

While preparing to physically relocate 14 milling and turning machines to his new building in Houston, Texas, owner James Wells decided it was the right time to examine every process at Wells Manufacturing for potential optimization.

He had just invested in a new, larger facility with bright lights and shiny new epoxy floors intended to represent the culture of quality at Wells Manufacturing. But it wasn’t until he had to clean out his machines for the move that he thought about the metalworking fluids going into them. After a decade of filling the sumps with the same product, he recognized an opportunity to try something new in hopes of further improving the new shop environment.

Mr. Wells met with John Hinders, the area manager for Blaser Swisslube, to discuss his options. “I suggested that Mr. Wells should try converting to one of our new products, Synergy 735. I thought it would improve the air quality and smell in the shop, and possibly improve tool life as well,” Mr. Hinders says.

Wells Manufacturing produces parts for many different industries, and that comes with a wide variety of materials including nickel-based alloys, hardened steels, stainless steels (including 13 chrome) and more. This makes Synergy 735 a particularly good fit for Wells Manufacturing because the metalworking fluid is specially developed for mixed production, Mr. Hinders says.

Introduced by Blaser in 2018, Synergy is a completely clear, water-miscible metalworking fluid with a neutral surface milling cutters odor. Despite the cleaner formula, the main concern at Wells Manufacturing was how a synthetic product would perform — and impact tool life — when used for machining tougher materials.

In 2018, Mr. Wells decided to test the new metalworking fluid in one of his Doosan machines. It didn’t hurt that he had a chance to meet Titan Gilroy of “Titans of CNC” at the International Manufacturing Technology Show (IMTS) that year. Mr. Gilroy was an early adopter of Synergy in his own shop.

“I think that Titan’s endorsement of Synergy actually got his curiosity aroused,” Mr. Hinders says. “They met at IMTS, and Mr. Wells really likes what Titan is doing at his shop and with his training initiative for the industry.”

More than a year after that first trial, Mr. Wells shoulder milling cutters reports improved air quality, lower consumption of concentrate, equivalent or better tool life, and much improved sump life. “I just cleaned out the sump on that first machine after a year, and it went much quicker because it really wasn’t dirty,” he says. “It used to be a lot more work and take all day, but now it’s done in three or four hours — less than half the time.”

After the success in the test machine, all 14 Doosan mills and lathes in the machine shop were converted to Synergy 735. The employees at Wells Manufacturing have noticed the difference, too. “My wife says she thinks I don’t go to work in a tool shop anymore, because I don’t smell like one when I come home. It’s wonderful,” says machinist Angel Arizpe.

“I’ve seen the difference in tool life firsthand after trying different coolants in the past,” Mr. Wells says. “Synthetics have a history in our industry of not handling tough materials well, and buying new carbide is usually one of the top four or five expenses in a shop. Blaser has overcome that problem with Synergy.”

Synergy 735 is a blend of polyglycols that is designed to provide higher lubricity and a neutral pH. According to Blaser, these characteristics support higher material removal rates while minimizing tool wear and delivering surface finishes comparable to those achieved with mineral-oil-based metalworking fluids. The synthetic formula is free of substances like bactericides, boron, formaldehyde, sulfur and chlorine, which can be damaging to the environment and dangerous to employees, the company says. Synergy 735 has been designed for excellent rinsability to ensure cleaner machines and parts. 

“Metalworking fluids are a small investment in terms of overall production costs, but they impact virtually every part of the manufacturing process,” Mr. Hinders explains. “Many shops don’t understand how important it is to invest in the right one for their application. But immediately extending tool life by even 10% contributes noticeably to the bottom line, not to mention the less-quantifiable benefits of a cleaner work environment.”

The Carbide Inserts Website: https://www.aliexpress.com/item/1005005878015710.html

Barton International has introduced the Trident-4 integrated diamond cutting head designed for Flow Dynamic Waterjet and Dynamic XD systems. The cutting head features the company’s cartridge technology, making it a direct replacement for Flow Paser-4 cutting heads without the need for an adapter. The company claims that the cutting head provides high accuracy and extended nozzle life, leading to lower operating costs and improved productivity. The cutting head is said to ensure orifice-to-nozzle alignment, which leads to optimal nozzle life. 

The Trident-4 has a diamond orifice which ensures that stream quality remains optimized over the life of the cartridge. Diamond wear resistance is said to improve gravity turning inserts total system performance. The head features a Roctec 500 mixing chamber and a 0.281" × 4" non-ringed nozzle. The replaceable diamond orifice cartridge can be swapped out for jobs requiring a different size of orifice. 

The Trident-4’s short stop filter prevents in-line contaminants from damaging the orifice assemblies by blocking debris from the most common sources within a high-pressure waterjet system. The filter features robust construction with a stainless steel mesh screen filter. The diamond orifice Carbide Turning Inserts cartridge is warrantied for 500 hours when used with a short stop filter assembly.

The Carbide Inserts Website: https://www.aliexpress.com/item/1005006185380264.html