Yet Another G-code Quiz!

Explanation
The correct answer is G28. G-code is a programming language used in CNC machines to control their movements. G28 is the specific G-code command that instructs the machine to return to its reference point, also known as the home position. This command is commonly used to ensure that the machine is in a known and consistent starting position before starting a new operation.

Explanation
The g-code for "return from reference point" is G29.

Explanation
The correct answer is G20. In CNC programming, G20 is the g-code used to specify that the input units are in inches. This means that all dimensions and measurements entered into the program will be interpreted as inches, allowing for accurate machining operations in the imperial system of measurement. G22, on the other hand, is the g-code used to specify that the input units are in millimeters. G54 is a g-code used to specify the coordinate system offset, but it is not specifically related to input units.

Explanation
The correct answer is G21. In G-code, G21 is used to set the units of measurement to millimeters. This means that any subsequent movements or commands will be interpreted and executed in millimeters.

Explanation
G38 is the correct answer because it is the g-code used to measure the diameter and center of a hole. G38 initiates a probing cycle where the machine moves towards the hole until it makes contact, measures the position, and calculates the diameter and center coordinates. This g-code is commonly used in CNC machining to ensure accurate hole dimensions and alignment.

Explanation
G48 is the correct g-code for "scaling off". G48 is used in CNC programming to cancel the scaling function. Scaling is the process of resizing or adjusting the dimensions of a part or object. By using G48, the scaling function is turned off, meaning that the dimensions of the part will not be changed or adjusted during the machining process.

Explanation
The g-code for "tool length compensation cancel" is G49.

Explanation
The g-code for "boring, no dwell, feed out" is G85.

Explanation
The g-code for "boring, spindle stop, rapid out" is G86.

Explanation
The correct answer is G82. G82 is the g-code used for a drilling cycle with a dwell. This means that the machine will perform a drilling operation and then pause for a specified amount of time before retracting the tool. This g-code is commonly used in CNC machining to automate the drilling process and ensure consistent and accurate hole drilling.