# What is the position tolerance?

Position Tolerance (symbol: ?) is a geometric dimensioning and tolerancing (GD&T) location control used on engineering drawings to specify desired location, as well as allowed deviation to the position of a feature on a part.
A.

### What is true position GD&T?

GD&T uses a notion called True Position when tolerancing locations. There are two forms of True Position–one for a feature size under a material condition (Maximum Material Condition or Least Material Condition), and one for True Position Regardless of Feature Size (RFS).
• #### How the straightness is measured?

STRAIGHTNESS MEASUREMENT. The straightness application is measured in two axis, where the laser beam is used as reference. The deviation in distance between the laser beam and the measurement object is measured in two or more positions with the use of a receiver. The program allows for up to 99 points to be measured.
• #### Do basic dimensions have a tolerance?

Question about a basic dimension without a specific tolerance. A – Basic dimensions by nature are a theoretically exact value; however, the feature(s) of a part they define as ideal or exact do need to have tolerances to permit acceptable levels of imperfection during manufacturing.
• #### What is meant by projected tolerance zone?

In geometric dimensioning and tolerancing, a projected tolerance zone is defined to predict the final dimensions and locations of features on a component or assembly subject to tolerance stack-up.
B.

### What is GD&T tolerance?

Geometric Dimensioning and Tolerancing (GD&T) is a system for defining and communicating engineering tolerances. It uses a symbolic language on engineering drawings and computer-generated three-dimensional solid models that explicitly describes nominal geometry and its allowable variation.
• #### Why do we use GD&T?

Geometric dimensioning and tolerancing is an international language used on drawings to accurately describe a part. The language consists of a well-defined set of symbols, rules, definitions, and conventions that can be used to describe the size, form, orientation, and location tolerances of part features.
• #### What is runout in GD and T?

GD&T Tolerance Zone: 2-Dimensional circular tolerance zone that is defined by a datum axis where all points on the called surface must fall into. The zone is a direct reference to the datum feature. Runout is the total variation that the reference surface can have, when the part is rotated around the datum's true axis.
• #### How the straightness is measured?

STRAIGHTNESS MEASUREMENT. The straightness application is measured in two axis, where the laser beam is used as reference. The deviation in distance between the laser beam and the measurement object is measured in two or more positions with the use of a receiver. The program allows for up to 99 points to be measured.
C.

### What is MMC and LMC?

MMC is the condition of a feature which contains the maximum amount of material, that is, the smallest hole or largest pin, within the stated limits of size. LMC is the condition in which there is the least amount of material, the largest hole or smallest pin, within the stated limits of size.
• #### What is shaft basis system?

GD&T limits and fits can be applied either by the shaft basis tolerance system or by hole basis the hole basis tolerance system. By and large, the hole basis system is most used in industry, unless there are multiple parts with holes are fitted with a single shaft.
• #### What is the feature control frame?

Definition: In GD&T, a feature control frame is required to describe the conditions and tolerances of a geometric control on a part's feature. The feature control frame consists of four pieces of information: GD&T symbol or control symbol. Tolerance zone type and dimensions.
• #### What is the position tolerance?

Position Tolerance (symbol: ?) is a geometric dimensioning and tolerancing (GD&T) location control used on engineering drawings to specify desired location, as well as allowed deviation to the position of a feature on a part.

Updated: 25th September 2018