The advantage is that a mill/turn center is equipped with both an upper and lower tool turret. Both turrets can be used simultaneously to cut on the part at the same time, ultimately reducing cycle time and increasing throughput.
However, as wonderful as this may sound, it can also be a problem. Each tool turret gets its own program. The turrets need to know what the other turret is doing so they don’t get in the way of each other and cause a crash.
Any part that requires both a milling operation and a turning operation. It is more efficient to drop parts complete using one machine than having to remove the part only to re-chuck it in another machine to cut additional operations. This saves a tremendous amount of cycle time, money and labor, and improves efficiency and part quality — all of which adds profits to a company’s bottom line.
Now this is a good question and is where mill/turn gets its name and earns its advantages. Most of the same milling operations that can be done on a standard milling machine can be done on a mill/turn center. The advantage to a mill/turn center is that it can hold a round part. A mill can as well, but not as easily, so fixturing may be needed. Another advantage is set-up time. Setting up one machine opposed to two different machines to perform different operations give the mill/turn center a huge advantage. Polygon milling, Y-axis milling, gear hobbing, involute milling, engraving and drilling (off-center and OD), are all operations that can be performed on a mill/turn center that can’t be performed on a standard milling machine.
All the turning operations that can be performed on a lathe or turning center can be done on a mill/turn center machine. A mill/turn center doesn’t necessarily gain production over a standard turning center, but the same operations can be done. However, there is one singular obscure advantage and that is that most true mill/turn centers have a tool changer so the number of tools that are available is substantially higher than on a standard lathe or turning center.
Often manufacturers are cutting parts one or two more axes to drop complete. If that customer would be open to learning just a couple more axes, they will begin to garner the skills it takes to operate a CNC mill/turn center safely and efficiently.
The answer is yes and no. Today, you can get a 3-axis mill for under $70K, and the same goes for a standard 2-axis lathe. However, if a heavy-duty mill or lathe is required, or a buyer begins to add many different options to the machine, that’s when metal cutting manufacturers need to start exploring a CNC mill/turn center.
For what the machine is capable of doing, a mill/turn center is worth the investment because it ultimately saves money by not having to purchase two machines that once again limit the company’s metal cutting capabilities. Investing in a CNC mill/turn center opens the door to bid for more complex work, adding additional revenue streams that positively affect the company’s bottom line.
At Absolute Machine Tools, our application engineers’ first step in determining which machine would be best suited to cut a particular part, is analyzing the size the part is to be machined down to. If the part is very large, then it cannot be cut on a mill/turn center machine because they are not made for hogging vast amounts of material off a blank.
Next, the team reviews the different types of metal cutting functions that need to be implemented to cut the part complete. Ultimately, it is the responsibility of the distributor to recommend the best machine to accomplish this task. What is best for a customer must be validated with facts to prove the recommendation is in the best interest of the manufacturer. Then, it is up to the end-customer if they want to make changes.
Throughout this process, it is imperative that the manufacturer trust the distributor’s recommendations. In the case of Absolute Machine Tools, our applications engineering team always presents the best cost-effective solution possible, because if we didn’t, then the manufacturer may never consider us again. It’s important to remember Absolute Machine Tools gets hundreds of part prints each year to evaluate, figure time studies and conduct prove-outs. Our applications engineers have seen it all, cut it all, and truly understand the capabilities of our CNC machine tools inside and out.
One CNC machine doing multi-cutting functions, such as a mill/turn center, is one of the first steps in automating — taking two machines and combining them into one to accomplish the same result. Adding a bar feeder to that machine exponentially increases production and efficiency for maximum throughput. However, if operators are manually loading blanks into the CNC mill/turn center rather than bars, then using a collaborative robot such as OB7 would be far more efficient both in throughput and ROI.
Shops that allow themselves the opportunity to embrace more efficient cost-effective metal cutting solutions will not have to worry about the current skills gap because they will require less manpower to produce the same amount of throughput and much much more.
The size of the part is the most important thing to consider when choosing the right mill/turn center. Most mill/turn spindles are 42mm, 51mm, 65mm and 80mm. After choosing the right spindle size, then consider if the machine has enough tooling capacity to make the part. Finally, take into consideration what other parts can be made and if the machine fits the bill for expanding the company’s capabilities to quote additional more complex jobs in the future.
No. All materials that can be cut on any mill or lathe can be cut on a CNC mill/turn machine, including plastic, brass, steel, stainless, titanium and cast iron, just to name a few.