When operating a boring bar excessive machining vibrations or chatter can occur because of several issues. To assure you’re maximizing efficiency and producing the best quality part finish, you must avoid basic mistakes that could be causing tool chatter in the boring process. In this blog we will discuss several tips to reduce and eliminate tool chatter.
When using a dull cutting tool, chatter will occur because the cutting force necessary is greater. The more a cutter is in operation, the more it will have galling or built-up edge (BUE). To avoid this problem, inspect your tool before operation to determine it has a a sharp cutting edge and fits your exact application.
Incorrect Speeds & Feeds
Using too high of a chip load in the boring process causes deflection, which increases the chances of tool failure. A chip load that is too low causes the tool to bounce off the material because it doesn’t allow the tool to cut enough. Both errors cause chatter and poor quality. It is critical to use the speeds and feeds recommended for the tool when running a boring bar.
No Workpiece Support
Poor or no support on the workpiece in the boring application will result in chatter. Be certain the correct workholding device is solidly set in place to ensure your setup is as rigid as possible. Secure tool holding is also essential for the proper boring performance.
Poor Starter Hole
Beginning a boring project by drilling a proper starter hole ensures the boring bar has sufficient contact with the workpiece for a stabilized cut. The boring bar could deflect off the workpiece if the starter hole is too large and will not have enough clearance if the hole is too small, leading to tool wear and eventual failure. The two critical dimensions to consider when selecting a drill to prepare the workpiece are the head width and minimum bore diameter.
While the process of boring enlarges generally pre-drilled holes, there are several machines that can accomplish this operation. In this blog, we will review the most common types of boring machines.
Horizontal Boring Machines
The most common boring machine is the horizontal machine. These widely used boring machines enlarge holes by utilizing a single-pointed cutter into the existing workpiece hole horizontally. They are found in many workshops offering repairs and small-scale manufacturing.
In addition to the boring process, this equipment can be used for milling, drilling, and reaming.
Vertical Boring Machine
The vertical boring machine enlarges pre-existing holes in a cylindrical or conical format. Using a rotary cutting piece joined to a horizontal table, the holes are usually concentric with the axis of the rotating cutters.
Table Type Boring Machine
These horizontally oriented machines are placed on the table using a spindle parallel to the work surface. Tabletop boring machines are used in general purpose manufacturing primarily by smaller machine shops.
Precision Boring Machine
Just like every other boring machine, precision boring machines enlarge existing holes in a workpiece. The machine uses a single-point cutting tool to widen a hole as the material moves parallel to the rotating cutters. This process means precision boring machines are perfect for producing large internal holes with tight tolerance and extreme precision specifications. In addition to making a hole larger, they can be used to straighten the initial hole and fix previous defects, all while maintaining a high level of dimensional accuracy.
Various industrial machining processes are similar to boring. However, the boring process delivers the best results when large holes require high precision and tight tolerances. To choose the correct method, it is essential to know the similarities and differences between boring and other machining techniques.
Poor quality in the boring process can adversely affect the quality of the finished product and cause future safety issues. To produce the proper bore, you need to understand the factors involved to avoid any issues that could occur during the process. Here are three of the most common boring issues you need to avoid assuring quality.
The process of boring is the perfect application to drill accurate and precise holes in various materials. While boring offers several benefits to machinists, it can also present challenges. As with any manufacturing technique, it is best to understand the challenges a process could involve before beginning a project. This blog will identify and discuss several of the main boring operational challenges.
It is common in manufacturing for parts and materials to go through multiple cutting processes to meet the product's exact specifications. This production includes producing holes in the material. While operations such as drilling create holes, boring works best for holes of different diameters, precision requirements, and positional specifications.
The process of finish boring requires an existing hole, and it is the perfect process for short-run jobs to remove the remaining stock in the hole. Finish boring offers more flexibility when machining different hole sizes using the same tool. Adjusting the boring head can compensate for the runout if the machine tool has more runout at the spindle. Also, a finish boring head can true up a hole more accurately than other applications.
Chatter or vibrations during boring operations is generally because of instability between the cutting tool ad workpiece. Often applying a larger-diameter boring bar will eliminate the problem. However, when a larger bar is not an option, there are options to reduce chatter that can reduce productivity and affect workpiece quality.
Boring is a different process from other hole making machining operations, such as drilling and reaming. Drilling is making an initial hole and reaming smooths out the walls of an existing hole. Boring is used to produce accurate size holes within required tolerance specifications using an existing pre-drilled hole. The following are some tips to assure your boring project meets your specifications.
Boring precisely enlarges existing holes in a part. Generally, boring on a turning bar is less complex than on a milling machine. A boring bar on a lathe can make any size hole if the bar will fit into the hole. Boring heads for milling machines have a limited range.
While the basic process of boring, enlarging holes that have already been drilled, sounds simple, it can become complex quickly. When the boring process involves intricate machined parts and materials the complexity of making pre-drilled holes larger, concentric, properly sized, or finished is more complicated projects. The following are types of boring that can get the complicated job done.