Frequently Asked Questions
Question: What is VoluMill?
VoluMill is a proven toolpath strategy that enables you to cut much faster and deeper than with typical toolpath strategies. At the same time, by avoiding sharp directional changes and controlling the rate of material removal, it can significantly extend tool life. It runs seamlessly inside of Siemens NX CAM, CAM Express, TopSolid, CAMWorks, NCCS, Cimatron, and GibbsCAM, with support for additional CAM systems on the way. It can also run as a standalone application - VoluMill NEXION.
Question: Is VoluMill a type of High Speed Machining (HSM)?
Well, yes and no. VoluMill does enable you to run your machine at high speeds, so in the most literal sense it is a form of HSM. But most of today’s HSM techniques use shallow depths of cut, and consequently have much more tool motion than traditional toolpaths; the machine moves faster, but rarely are the parts cut in less time. VoluMill toolpaths take a completely different approach whereby the increased feeds and speeds actually yield significantly shorter cycle times.
Question: Is this just a new type of optimizer?
No. By definition, toolpath optimizers begin with a CAM system-generated toolpath and modify it in hopes of making it better than it was originally. This involves attempting to detect where the tool is likely to become overloaded and then modifying the path to lessen the impact when milling in those areas. More often than not, this post processing of the toolpath consists of adding new blocks of code to insert feedrate reductions in the corners.
VoluMill, in contrast, is a completely new toolpath strategy that drives machine tools and cutting tools to their fullest capabilities. It is not based on any previously existing strategy, and therefore generates toolpaths that are inherently free from the problems of CAM system-generated toolpaths. There are no problem areas, so there are no modifications that need to be made. There is therefore absolutely no need to run a VoluMill toolpath through a post-processing optimizer. Indeed, if you own such an optimizer, please don’t use it on a VoluMill toolpath; it is unnecessary, and will almost certainly reduce VoluMill’s effectiveness.
Question: Is VoluMill a type of trochoidal toolpath?
Not at all. So-called trochoidal toolpaths employ a looping motion in an attempt to avoid burying the cutting tool. VoluMill toolpaths, on the other hand, are designed so that the tool will never be buried, thus eliminating the need for the toolpath-lengthening circular motion; a VoluMill toolpath is therefore significantly shorter than a trochoidal toolpath for the same geometry, resulting in shorter cycle times. In addition, since the load on the tool is precisely controlled with a VoluMill toolpath, more aggressive machining parameters can be safely used than with a trochoidal toolpath. The net result is that a VoluMill toolpath is significantly more productive than a trochoidal toolpath, while at the same time putting less stress on the cutting tool, thereby extending tool life as well as reducing cycle times.
Question: Does VoluMill avoid burying the tool by shaving material away with many light cuts?
No. Unlike other toolpath strategies, VoluMill intelligently leverages many different techniques throughout a single operation in order to generate the best cycle times and best tool life for your needs.
If you choose, VoluMill can enforce a side milling strategy that prevents the tool from ever moving farther than the programmed stepover from the previous cut. This option is particularly useful in hard metals, where it may be undesirable to fully bury the tool. Although some looping motion will occur, the looping occurs only when absolutely necessary; unlike many other strategies, a VoluMill toolpath is designed to maximize the amount of long, smooth, racetrack-like cutting.
For softer materials such as 6061 aluminum, or light axial depths of cut with large stepovers, you may choose to allow slot milling as well as side milling. If so, VoluMill will automatically choose side milling or slot milling on a case-by-case basis during toolpath generation in order to minimize the cycle time. When slot milling occurs, VoluMill will slow down the cutting feedrate and/or reduce the axial depth of cut to keep the material removal rate constant. The user can override this behavior for even greater control.
The upshot is that regardless of your material, machine, tooling, or part shape, VoluMill can give you better cycle times and tool life than you ever thought possible.
Question: Does VoluMill control the tool's engagement angle with the material?
Not in the least. VoluMill toolpaths are based on a constant stepover. A constant-stepover toolpath, by definition, is not engagement-controlled. However, VoluMill does carefully adjust cutting feedrates to control the rate of material removal. When coupled with VoluMill's smooth, carefully controlled motion, you can get much higher material removal rates and better tool life than you are used to, with significantly less tool motion and cycle time than an engagement-controlled toolpath.
Question: How do I determine what feedrate, spindle speed and depth of cuts to use?
This is an excellent question, since VoluMill toolpaths are breaking the milling rules that have been in play for decades. Customers are achieving amazingly fast cycle times due to the aggressive parameters that can safely be used with VoluMill. Customer-proven parameters for various materials can be found on our cutting data page which will continually expand, so please check back often. If the material, cutting tool, or machine tool you have isn’t represented there, the following is a rule of thumb that has proven effective at determining good starting points:
Start with the cutting tool manufacturer’s recommended values for surface speed and feed per tooth, and triple them. Make adjustments (typically upwards) from there based on how well it is cutting. For harder, and harder to machine, materials (stainless steels, tool steels, titanium, and exotics, for example), most customers have found that a deep axial depth of cut combined with a lighter radial width of cut (10% to 20% of the tool diameter) works best. Also, don’t be afraid to use 5- or even 7-fluted tools for roughing; the managed material removal rates that VoluMill provides makes this not only possible, but desirable. For softer, freer machining materials, like aluminum, increase the cut width along with the speed, feed, and axial depth. You may find that your only limitation with these materials is a physical limitation of your machine, such as the RPM or cutting-feed capability.
As you experiment with VoluMill in your shop, we encourage you to share your experiences with us so that we can continue to refine the answer to this question.
Question: How do I determine the best tool to use?
VoluMill will improve the performance of any cutting tool. But it really helps in yielding the maximum return on investment in higher-quality tools. Since VoluMill drives cutting tools as they were designed to be driven, the highest productivity increases can be achieved with better cutting tools. We and many of our customers have experienced excellent results with tools from a wide variety of manufacturers. As mentioned in the answer to the previous question, tools with more flutes tend to work better with VoluMill. Since the material removal rate is precisely controlled, chip clearance is not a problem, and the greater number of flutes results in a faster feedrate at the same feed-per-tooth value. In addition, the more flutes a tool has, the stronger its core is. We have found that 3-flutes are ideal for aluminum and softer materials, and 5-flutes have performed well in a wide range of harder materials.
Tool diameter is also something to consider. VoluMill toolpaths reach their highest actual feedrates when the tool has more room to “stretch its legs”. For example, many customers have realized their greatest cycle-time reductions by dropping down in size from 3/4-inch or 5/8-inch tools to 1/2-inch tools when converting from traditional toolpaths to VoluMill toolpaths. The added bonus there, of course, is the lower cost of the smaller tools.
Question: What kinds of parts can I cut with VoluMill?
VoluMill can be used to rough mill any part that you can rough mill, in 2- or 3-axis, with your current CAM system. It has always excelled at machining prismatic parts. Customers quickly find that VoluMill toolpaths are easier and faster to generate than the toolpaths that are native to their CAM systems – there are fewer parameters to enter and fewer decisions to make – and the performance on the shop floor is unparalleled.
Question: What kinds of material can I cut with VoluMill?
Our customers are using VoluMill to machine aluminum, exotic nickel-based alloys, and everything in-between, all in dramatically faster cycle times. VoluMill toolpaths establish optimum machining dynamics and maintain them throughout the length of the toolpath, regardless of the shape of the part. As such, the toolpaths are very effective across all material types.
Question: Does VoluMill work on hard metals?
VoluMill works especially well in hard materials. The penalty for employing poor machining dynamics is more severe in harder materials than in softer materials, both in machining times and in cutting tool life. Therefore, the ideal machining dynamics inherent to VoluMill toolpaths pay their biggest dividends in harder-to-machine materials. VoluMill customers machining Inconel have reduced their rough milling cycle times by 80%, while extending their cutting tool life by a factor of four. One customer milling Waspaloy reduced the roughing time on one part from one-hour-twenty-minutes to three-minutes-twenty-seconds. We didn’t believe it either until we actually saw it, but it is absolutely true.
Question: I have an older, less capable machine tool. Can VoluMill still help me?
VoluMill can help any machine tool run more productively with reduced stress. VoluMill ensures that the toolpath will not be the limiting factor in your machining productivity. In your case, your machine tool is the limiting factor. But although older machines won’t allow VoluMill to provide the productivity increases you’ve heard of others achieving, you still can benefit in many ways. The consistent load on the cutters will extend their useful life, dramatically reducing cutting-tool costs on a per-part basis. The uniform chip formation will significantly improve heat evacuation, which extends tool life and improves part quality, especially with thin-walled parts and materials that are prone to work hardening. Your spindle loads will be dramatically reduced, which will help you get even more years of service out of your machines, with reduced maintenance issues. You will be able to run comfortably as fast as your machine will allow, without overtaxing it. When you do upgrade to a new machine, VoluMill will ensure that you get the maximum return on that investment. But VoluMill will have already paid for itself many times over by then.
Question: How do I set up a test?
The best way to learn about the benefits of VoluMill is by validating the technology. Celeritive has developed a unique approach in helping manufacturing companies quickly identify the benefits of VoluMill without having to spend much time or resources in doing so. Contact Celeritive Technologies, or one of our certified resellers closest to you and ask about the VoluMill Challenge.
Question: How much does it cost?
VoluMill is a very economical enhancement to your CAM system and can generate a payback in your very first run. Please contact Celeritive for information specific to your CAM systems, or your CAM reseller to purchase.
Question: Do you have network licenses available?
We can match your network license needs/requirements. VoluMill is available as a Node Locked license, a Standard Floating license for up to five registered users, and an Enterprise license for unrestricted use across all geographical locations of your enterprise.