About Advent Tool's Spline Milling Product Line (formerly TMFM LLC)
Spline Milling Tools For The Future
TMFM LLC., was established in 2006 as a subsidiary of our parent company, Advent Tool & Manufacturing Inc., founded in 1974. This division was created to specialize and focus entirely on making spline, gear and custom form milling cutters. Since then TMFM has been supplying high quality custom and standard tooling to customers from around the world. We have had successful implementation of our cutters in various applications ranging from one-off prototype jobs to high volume production tooling. As of December 31, 2014 TMFM LLC has merged with Advent Tool & Manufacturing, Inc.
The ultimate goal of our Advent Tool engineering and manufacturing team is to provide manufacturers and machine shops across the globe with milling tools that can perform: spline, gear, and custom form milling while maintaining the highest quality industry standards and consistently allow companies to perform manufacturing processes in-house that were not previously achievable.
Advent Tool & Mfg., Inc. has been turning spline milling upside-down of late! With our tool design and process now patent-pending, Advent Tool has further developed these spline milling tools to incorporate prototype work as well as production applications. But first, let’s talk about the process in general terms. Take an innovative and proven standard multiple flute indexable cutter body traditionally used for other types of form milling. Combine it with a customized insert for cutting spline forms. Now Advent Tool has combined an old technology with new to bring spline ‘hobbing’ to a whole new paradigm: into a ‘milling’ paradigm, if you will. These spline milling inserts are NOT made in matched sets. They are individually produced to a repeatable Advent Tool standard that is the same across the application spectrum.
This technology is brought to bear with more predominantly available CNC machines than would typically be used in the spline hobbing process. All that is needed with the Advent Tool spline milling system is a rigid setup with either a Horizontal or Vertical Machining Center with a 4th Axis Rotary Table. Advent Tool has also applied this milling system with even greater success in CNC Mill/Turn equipment as well! From a lean-manufacturing perspective, the Advent Tool solution provides for a smaller number of setups and less capital equipment outlay. The reduction of cycle time is the most immediate and tangible benefit. Advent Tool has seen some cycle time reductions as great as 1200%! As in the picture below, the rotary table holds the work piece in a fixed position. The cutter runs in a straight line in the ‘Y’ Axis – generating a climb-milling cut. The rotary table is programmed to index the part the correct number of forms to suit the insert (5 teeth for a 5 tooth-form insert, and 1 tooth for a 1 tooth-form insert).
Considering a specific spline form, for example, a 1.44” 24/48 pitch spline; Advent Tool will grind this form from print into a solid carbide insert blank. Dependent upon the work piece diameter; which, along with pitch is the limiting factor; Advent Tool can provide a tool with as many effective teeth as possible in the spline form simultaneously. Due to the length of the insert, multiple redundant (or even different!) forms can be produced also to maximize production from each insert.
The advantages of the Advent Tool solution do not stop there, however. The Advent Tool process involves milling the spline form whilst the ‘C’ axis is stationary and cutting the work piece to the end of the form. Afterwards, the ‘C’ axis is indexed to bring more of the blank work piece material to bear. The index amount directly depends upon the spline form on the insert. Single or multiple teeth cutters are used based on whether there are production (multiple) or prototype (single) volumes in play. Since straight-line milling is utilized in the cut, programming and time spent dialing in feeds and speeds for these applications is vastly reduced over what is seen in traditional spline milling and helical interpolation (3-Axis Simultaneous) milling code!
So the question is raised, why does Advent Tool call this process ‘Milling’ instead of ‘Hobbing?’ Factually put, Advent Tool is using an indexable milling tool, rather than a High Speed Steel (HSS) or carbide spline hobbing tool. A carbide tool solution in spline milling equipment is almost unheard of, although they are in use in a few production manufacturing situations. Existing, dedicated spline hobbing equipment, such as a Barber Colman ® Spline Hobbing machine is not, regrettably, capable of running carbide efficiently – it just isn’t made for the speeds that carbide needs to run effectively. It is not easy these days to find a knowledgeable individual that knows how to set one up either… Literally speaking, Advent Tool is running spline form tools on vertical machining centers in ferrous materials at upwards of 2,500 Surface Feet per Minute! Just a little bit faster than HSS tools would perform in similar conditions…