Hand reamers are small cutting tools used to refine holes to an exact diameter. They consist of a metal shaft with flutes and a square end for a wrench handle. There are fixed and adjustable diameter hand reamers, used for high precision machine tools. Hand reaming achieves a high degree of accuracy, with a tolerance of up to 0008 inch, and is commonly used to finish dowel or stud holes.
A hand reamer is a small hand cutting tool used to refine holes drilled or machined to an exact diameter. These tools consist of a metal shaft made from a hardened tool steel alloy. Along a portion of the shaft’s length, there are several flutes or shear blades arranged in a circular pattern of fixed diameter. The other end of the shaft is machined into a square that fits a key wrench handle. Hand reamers are commonly used in machine shops to repair and manufacture high precision machine tools.
Many hand reamers are slightly tapered and chamfered near the end of the shaft, as this allows for easier insertion into an existing hole. However, some hand reamers are not tapered or chamfered and are used when the full depth of the hole needs to be reamed to size. Once inserted into the hole, the hand reamer is rotated slowly by hand, usually with the aid of a male wrench handle. The blades on the shaft remove only the small amount of material needed to finish the hole to the desired size.
There are two main types of hand reamers available: fixed or adjustable diameter. A fixed diameter hand reamer has cutting flutes that have a fixed diameter and can only be used to finish holes to that diameter. They are available in sizes ranging from 1/16 inch (1.59 mm) to 2 inch (50.8 mm). Flutes are machined into the shank of the reamer and a cutting edge is applied during the manufacturing process.
An adjustable hand reamer has a series of adjustable blades that ride in conical slots cut into the shank. The shank is threaded and two threaded adjustment rings are positioned at either end of the blades. The cutting diameter is adjusted by loosening one adjusting ring, sliding the blades to the new position, then tightening the other adjusting ring. Since the flutes are tapered, the effective cutting diameter is changed with each new adjustment. This range varies in size depending on the size of the hand reamer being used. They are available in sizes ranging from 1/4 inch (6.35 mm) to 3 11/32 inch (84.93 mm). Adjustable hand reamers are commonly used to cut odd sized holes when a properly sized fixed diameter hand reamer is not available.
Hand reamers are often used in machine repair work and in machine tool manufacturing which require a high degree of accuracy. A hole tolerance of up to 0008 inch (02 mm) can be achieved with the use of a hand reamer, compared to a tolerance of 003 to 005 inch (08 to 12 mm) when drilling. Hand reaming is often used to finish dowel or stud holes to size to allow for an interference fit between the hole and dowel. When used properly, the hand reamer only removes a small amount of material at a time, usually only 005 to 008 inches (12 to 20 mm). Consequently, hand reaming is highly desirable to produce a high quality finish on the bore surface.
Protect your devices with Threat Protection by NordVPN
