High speed spindles are ideal for solving many production challenges today. Whether you need to drill tiny holes, create a super finish on a mold or just produce aluminum components quicker, a high speed spindle can be the ideal tool to get the job done. So, if one high speed spindle boosts production, why not use two, three or more? Of course, you’ll have to take the cost of additional spindles into consideration to see if this approach makes sense.
Multiple spindle systems can be designed to solve a variety of problems. Here are some examples of how they can be used to solve various production challenges.
High Volume of One Feature – Multiple Spindles on One Machine
In this example, let’s say a shop needs to drill many holes in a single plate, very close together. The end result is a perforated part that looks like a screen. A single high speed spindle can do a great job of quickly drilling each hole. However, drilling thousands of holes would take too long. So, by setting up multiple high speed spindles, at a fixed centerline, it is possible to drill as many holes as you have spindles. The math is simple. If you need to drill 1,000 holes, with ten spindles, it would take 1/10 of the time when compared to drilling 1,000 holes with only one spindle. This technique is effective as long as you only need to use one end mill or drill. One important note regarding this type of setup. You’ll need to make sure there is a way to adjust the tool length offset for each individual spindle. This can be done by mounting each spindle on an adjustable sub-slide. If you need to use more than one tool, there are other solutions to consider.
High Volume of Parts, Different Features – Swiss Style Turning
A very common application for multiple high speed spindle installations is on Swiss turning machines. In this example, a customer produces a very high volume of parts, but also must change over and produce different parts at high volumes. To minimize change over and setup times, they decided to install a large quantity of high speed spindles that were positioned and tooled up to allow very easy and quick transitions to different part production. The quantity of spindles varies from a low of two or three on one machine to as high as 16 spindles on one machine. This can be an expensive solution, considering the investment required for all those high speed spindles. In this case, a custom drive and control system was implemented that helped mitigate the cost. The flexibility and elimination of setup down time easily justified the financial investment.
Multiple of Same Parts, Different Features – Hybrid Machine
A common solution for producing parts on machining centers is to make more than one part at a time. It is a shame to waste the unused space on the machine table. For moderate production quantities, it is very common to clamp one, two or more parts. In some applications, a high speed spindle is the ideal tool to use for certain features, such as slotting, drilling or contouring. One solution is to replace the standard CAT40 spindle with a high speed one. This is a great solution, as long as the high speed spindle can provide the best productivity. However, this is not always the case. A high speed spindle typically cannot use large tools.
In the next example, a manufacturer of electronics systems needed to produce aluminum antennae components. These parts required the use of small diameter cutters, so a high speed spindle was needed to optimize the process and minimize the cutting time. However, the parts also required some big face mills and rough cutting, which was better performed using the high torque, low speed, CAT40 main spindle. The solution for this customer was to build a special twin-spindle system that was mounted to the side of the main spindle. The high speed spindles were capable of 35,000 RPM, and even featured a table-mounted tool changer for the high speed spindles. The high speed spindle CNC machine integration could be completely programmed for spindle operation, speed and ATC. This hybrid machine system was used on multiple machines for many years with great success.
Conclusion
Using multiple high speed spindles has definite advantages for certain types of parts. If you have a high volume of a special feature made with one tool; drilling, slotting or contouring, you may consider a multi spindle machine. On Swiss turning, a high speed spindle will always outperform the driven tooling for small cutters, and multi spindles are pretty common. If you are tasked with producing large volumes of identical parts, you may consider building a hybrid machine, taking advantage of both the main traditional spindle and using high speed spindles to speed up the cycle time killing features.
