A taper reamer is a tool that is used to correct the geometry of a taper that may be present within the machine’s spindle. Should the spindle have any gap or wobbles, a taper reamer can remove small amount of metal from the spindle to ensure the spindle is precise and accurately defined. However, you must use the correct taper reamer because the taper itself is specific to the machine; if the taper of the taper reamer does not match the taper of the machine, then the taper reamer will not be able to fix the hole in that machine, and could potentially ruin the machine altogether.
There is different types of tapers that are defined for different manufactures and machine models; the machinist must determine the specific taper of the machine prior to purchasing the taper reamer. For instance, if a Morse taper reamer is purchased for a machine that features Brown and Sharpe tapers, the Morse taper will not work within that machine model; using the wrong taper reamer will introduce errors into the machining process. Within the market for taperreamers, there are two main type of taperreamers that can be purchased: hand reamer and machine reamer.
How to Choose and Use a Taper Reamer
A hand reamer typically features a square shank that allows it to be held within the machine, and the machinist’s hand can turn the reamer slow. A hand reamer allows for more control of the taper reamer, while a machine reamer is better suited for machines that requires the creation of many tapers; a machine reamer will mount directly into the machine, and typically features a higher rotational speed than a hand reamer. The geometry for a taper reamer is created according to the taper per foot measurement for that specific machine.
The taper per foot for a taper reamer will define the angle of the slope of the taper reamer; this angle must be the same than the angle of the hole within the machine. Should the taper per foot measurement be incorrect, the taper reamer will not create a wedge that will lock into place within the machine through friction; using the incorrect taper per foot will create a gap within the machine’s spindle. In order to ensure that the taper reamer will create a precise fit for the taper, it is important to make sure that the taper size of the taper reamer match the machine standard.
The material of the taper reamer should match the material of the workpiece. High speed steel is a common material for taperreamers, and high speed steel is easy to sharpen. Solid carbide materials are harder than high speed steel tool, and will last longer when cutting elements like hardened steel.
However, solid carbide materials are brittle, and can snap if the taper reamer setup are not rigid. Finally, cobalt material are an option for reaming stainless steel elements due to the abilities of cobalt to handle heat. When using a taper reamer it is important to adjust the RPM of the tool.
Taperreamers should not spin at the same rate as drill bit. Instead, the RPM should be lower when utilizing a taper reamer. This is because taperreamers remove a tiny amount of material to create a perfect fit for the component that will feature the taper.
If taperreamer bits are spun at high RPM values they will create chatter on the workpiece and create oversized hole. Additionally, the operator should utilize lubrication when using taperreamers. Heavy sulfurized oils should be used for stainless steel components and light mineral oil for aluminum component.
Maintaining a film of lubricant between the taper reamer and the workpiece is necessary. Without lubrication there will be friction between the taper reamer and the workpiece, leading to the production of heat that will ruin the taper. Furthermore, if lubrication is not used the heat will damage both the taper reamer and the workpiece itself.
