Chatter is something that every CNC’er must deal with. While it doesn’t matter if the chatter is from the tool or the work, how you deal with chatter does matter. We aren’t talking about the chatter during smoke breaks or the chatter in the lunch room, we’re talking about the resonance caused when either the tool or the piece you are working vibrates. Chatter isn’t the fault of the tool, the workpiece, or the machinist. Chatter is just physics in action. Chatter occurs at all speeds and with all materials. It is more problematic the faster you machine. Chatter must be dominated and controlled!
You get workpiece chatter when the wall of your work starts to vibrate. You can minimize this by maintaining as much rigidity as possible in workpiece for as long as possible.
You can remove less material in each pass and make more passes. The CNC Cookbook even recommends adding rigidity by adding a material that is easily removed once the work is done. They go as far as recommending a mixture of petroleum jelly and lead shot!
Workpiece chatter can become more pronounced when you are literally cutting corners. The engagement increases the number of teeth in the cut. This drastically increases the cutting forces, causing chatter. You can use a larger initial radius to make the first cut, and then remove the remaining stock in another pass.
This is the home of chatter. The machine, the tool holder, and the tool are all ripe for chatter problems. That’s because they all want to vibrate naturally as they move. Don’t let chatter be the defining parameter of your machining. Be defined by the limits of your machine, your tool, and your material. Here’s some things to keep in mind in reducing chatter.
Speed. You may instinctively want to go slower. Fight the instinct. Speeding up might be the right thing to do. If you start to get chatter, try speeding up. You might find that the sweet spot is higher; not lower. If you want to do it right, then you need to create a Stability Lobe Diagram. If you can handle the math, do it yourself. There are also companies that specialize in analyzing your tooling equipment and creating the diagram for you.
Tool Deflection. The manufacturers of milling machines advise that chatter cause problems when tool deflection exceeds 0.001″. Use your software to calculate cut width and depth to make sure you stay within that parameter.
Saw Arbors Built to Minimize Chatter
You should also invest in saw arbors that were built to minimize chatter. When you know CNC you know that chatter is natural, you just must allow for it and work towards ways to reduce it. Sierra American Multi-Systems knows CNC. That’s why they’ve invested in Vibra-Core technology to reduce cutter vibration.
Vibra-Core is a special heat-treating process that give rigidity and extra support. Every saw arbor sold by Sierra American incorporates Vibra-Core in the design.
Quality Saw Arbors Made in the USA
For quality saw arbors that reduce chatter, choose Sierra American. Every saw arbor made by Sierra American is:
- Made in the USA
- Designed with Vibra Core to reduce chatter
- Made with Weldon shaft
- Engineered with extra long reach out
- Provides closest cutter to work area in the industry.
Sierra American saw arbors are available in a range of sizes. Custom arbors are made upon request. If your supplier doesn’t have Sierra American Multi-systems tools, ask them to order them.
Don’t get ripped off by cheap imitators. Insist on Sierra American and ask for it by name. Call (800) 576-5331 to find the supplier near you.