Turning: Production Machining

David Fischer:

You know the saying, if you aren't moving forward, you're going backward. There is no standing still. A common quote we often hear thrown around, to the point of becoming cliche, but we all know that there is a lot of truth in it. A quote that I like by Tech blogger, Graham Wood is, "Change has never happened this fast before, and it will never be this slow again."

David Fischer:

Put another way, if you're standing still, you're falling behind faster than ever, and it's only going to get worse. My name's David Fisher and I'm the Lathe Product Specialist at Okuma America Corporation. Today I want to talk about moving your shop forward, gaining, and maintaining a competitive edge.

David Fischer:

So, enough of the negative talk. The good news is that it has never been easier to turn things around. There are so many easily accessible resources out there. One key resource is your machine tool provider.

David Fischer:

Speaking for Okuma, we work closely with our distribution network to provide solutions tailored to our customers' requirements through our long history of working together. Okuma has partnered with top level providers of work holding, tooling, gauging, software, and accessories. They can provide technical expertise and assistance as well as world-class products.

David Fischer:

Although we will be focusing primarily on machine selection, I think it's always important to provide some quick, actionable improvements using technologies that may already be available on your machine. So take advantage of the technologies you already have.

David Fischer:

Today, CNC controls are extremely powerful and have many built-in features that most do not even use. Take some basic functions, such as load monitor or tool life management. These are standard on Okuma OSP controls and can improve your productivity in many ways. For example, increased tool life and failure avoidance, decreased soft metal costs due to tool failures, decreased scrap, increased production.

David Fischer:

Your process will guide you. Every time you have a processing problem, it's a chance to improve it. Almost lose a drill because the chips loaded up? Add load monitor to shut it down first. Lose a roughing tool, because an insert wasn't changed in time? Add tool life management and load monitor. Just use it where needed and implement in steps. Baby steps every day will have a huge impact on your shop over time.

David Fischer:

Finally, look into the app store at Okuma for downloadable applications that will let you customize the control to suit your needs. Many controls have the capability to add apps. At Okuma we offer the app store, which has a variety of applications to download many for free.

David Fischer:

Here are just a few examples of what is available. In addition, with the build an API supply with every OSP control, you have the ability to create your own custom applications.

David Fischer:

Now let's move on to machine selection. In most production situations, one of the biggest improvements you can make is through process integration. As lot sizes get smaller and the environment we live in requires shops to be able to quickly pivot from one type of part to another, adaptability and flexibility are critical.

David Fischer:

Adding capability to the machine tool, whether that's just basic milling or a full-on multi-tasking machine provides the ability to pivot quickly, which makes you a more valuable partner to your customer and lets you take advantage of opportunities that arise unexpectedly.

David Fischer:

So let's start with the basics. This part was just completed on the lathe, but there are four bolt holes and the side vent hole that must be machined. Would it be better to move it to a machining center to drill the holes or just go ahead and do it on the lathe?

David Fischer:

On the lathe I already have it clamped. I already know where my X, Y and Z zeros are. Wouldn't it be better to just drill the holes in the lathe rather than set up a second machine to drill the bolt holes and a second setup or second vice on the table to drill the side hole while maintaining relative positioning between all the features?

David Fischer:

Looking ahead, if there was a design change, wouldn't it be easier to accommodate that change if I machine this part complete on the lathe? Machining it complete on a single machine would, in most cases, get it out of the shop in the shortest amount of time. Since there are fewer process interruptions, the operator would have more time to keep up with part measurement and any other tasks that are required.

David Fischer:

Breaking that total cycle time into four operations means four times the work for the operator and the increased possibility of operator error. In most cases, keeping the process in as few machines as possible is the most efficient way to produce this part.

David Fischer:

Let's look at the second part. Again, we could move it to a machining center for the mill drill work, but that just adds unnecessary complications. Just like the last part, I already have it clamped. I already know where X, Y, and Z zeros are. Completing the mill drill operations on the same machine would generally make the most sense.

David Fischer:

In this case, I'm going to add Y-axis to the machine's capabilities, although it would be possible to machine this part without a Y-axis, the Y-axis does provide for more efficient milling and makes it easier to size features, especially with tight tolerances. By keeping this on a single machine, I can get it out of the shop faster.

David Fischer:

In both of the previous examples, the operator is still required to flip the part in order to machine both sides. Adding a sub-spindle eliminates this requirement and means that the part comes out of the machine complete. Since the orientation is maintained between the main and sub-spindle, there are no concerns about the relationship of features on the first and second side.

David Fischer:

It also permits the deburring of the part. Since the part orientation is maintained between spindles and burrs created on the second side can be accurately and efficiently removed.

David Fischer:

To maximize your shop's ability to adapt on the fly the best way is to move to a full-on multitasking machine. These machines add a B-axis that made quick work of angled features, an automatic tool changer to provide the right tool for the job, and a powerful milling spindle to perform efficient milling and drilling operations.

David Fischer:

Full 5-axis capability is available as well. These machines can also be used to perform hobbing and skiving operations, permitting the integration of even more processes. When looking at a process integration, it's important to look at lot sizes. Are your lot sizes declining? A common situation we often see.

David Fischer:

In some cases, we have seen a process geared to large lot sizes still being used when those lot sizes have been significantly reduced. The original process was geared to making as many parts as possible in the shortest amount of time, but due to the need of reduced inventory, lot sizes were slowly reduced and it's now more important to be able to have quick changeover, to respond to their customers rapidly changing demands.

David Fischer:

Let's take a look at other production situations. In this case, we have a shaft part that provides a lot of opportunity to reduce cycle time, if we can apply two tools at the same time. Now a second turret by itself, won't cut your cycle time in half, but you can make a significant cycle time reduction.

David Fischer:

Looking at this part, we can use pinch turning to rough and finish turn the OD. The four grooves and the barbs can be performed simultaneously. Same for the two threaded features and the wide groove at the front can be roughed out using both turrets and then finished with a single tool to eliminate any mismatch and make offsetting easier.

David Fischer:

By flow charting the process, it's easy to see how much time we saved taking over two minutes out of the cycle time. By properly applying 4-axis machining, we can produce more parts per machine, per shift, and per operator.

David Fischer:

Although shaft parts are generally the easiest parts for twin turret applications, there are a lot of other ways to make part processing more efficient, such as lower turret mounted steady rests, and simultaneous OD and ID work.

David Fischer:

In this video, we machine the OD and ID simultaneously with a cutting tool, supporting each other, eliminating the chatter common on thin wall parts. For high production of complex parts having a two- or three-turret machine with opposed spindles can be a real time saver.

David Fischer:

Here we're showing our three-turret machine where each of the upper turrets are dedicated to a spindle and the lower turret can work on either spindle. This lets you use the lower turret to balance the cutting process and minimize takt time.

David Fischer:

When doing bar feed feed work, these machines make it easy to automate the process. A barfeeder, sized to meet production requirements, easily moves material into the machine. From there a simple parts catcher can be used to remove the finished part or for more delicate parts, the available built-in unloader is an option that can gently remove fragile parts from the sub-spindle without damaging them.

David Fischer:

In this example, the first operation requires more machining time, so we can use the upper left turret and the lower turret on op one while the upper right turret works the right spindle for op two. Besides simultaneous turning, we can also do simultaneous milling further reducing cycle time shown here using the optional Y-axes.

David Fischer:

Turrets can run independently or be synchronized as required. The optional built-in unloader can quickly and safely remove parts from the right spindle without damage and can do so while the left spindle is machining.

David Fischer:

Although the machine tool is generally the biggest piece of the puzzle for your production process, there are a lot of other components that are required to successfully and efficiently machine a quality part. Therefore, it is important to have a network of experts for every part of the production equation. Having a close working relationship with your tooling, workholding, software, and other suppliers helps you stay current with the latest technology and also provides you with invaluable practical expertise.

David Fischer:

At Okuma we have our Partners in THINC facility where we work with industry-leading experts, creating complete solutions for our customers. Partners in THINC is a collaborative network of more than 40 companies that service the metal cutting and manufacturing industry. These partners come together to solve problems and explore new productivity ideas for real-world manufacturers.

David Fischer:

While this collaboration started as a proving ground for our open architecture PC-based OSP control, Partners in THINC has evolved to educate and transform modern manufacturing principles. Today, through our partners’ specialized equipment and unique expertise, we continuously provide streamlined solutions to our customers.

David Fischer:

So this is just a quick overview on how to use technology to gain and maintain a competitive edge in a challenging marketplace. Certainly, there is more than can be covered in this short presentation and each situation is different. But the important thing is to make the decision to move forward. Doing something involves risk, but doing nothing involves more risk.

David Fischer:

Thank you for your time and check out our website www.Okuma.com to get more information about Okuma machine tools as well as our partner program.