This is a reference dimension. I.e. the part can and should be manufactured without using it directly. The non-bracketed dimensions should define the form of the part completely.
An underline on a dimension means that it is not to scale.
isometric drawing create the illusion of 3 dimension by drawing the depth of the object on the both side.. in isometric drawing they are both set on the 30 degree angle..
Generally it means that the dimension is for reference only. The actual (real dimension) will show up somewhere else on a drawing. It could also be put on a dimension that you really don't want an inspector to hold tight (material thicknesses that vary with vendor or batch run)
If the scale is 1 to 16, then each dimension in the real world is 16 times its size on the drawing, and its size on the drawing is 1/16 of its real size. The barn must be drawn 2-ft high on the plans.
there are several different types of lines used in dimensional drawing, most are vertical and horizontal in design.
An underline on a dimension means that it is not to scale.
NTS
The first dimension string on an architectural drawing should begin at the point representing the starting reference point of the dimension being measured. This point is typically indicated by a small arrow or dot.
No, then it would not be a reference dimension. Reference dimensions by definition have no tolerance.
.125 STOCK
relative and polar
A 3D drawing is a three dimensional drawing. There are a number of ways an artist can convey dimension in a drawing. Perspective is one of them. Shading and contouring are others.
An orthographic drawing attempts to represent a 3D picture in a two dimension drawing. Usually shows a front, side and plain view
Dimensioning standards are official guidelines that define how measurements, notes, and symbols are presented on technical drawings to ensure clarity and accuracy. They establish rules for line types, arrowheads, text size, and placement of dimensions to avoid confusion during manufacturing or inspection. Following these standards ensures that the drawings are universally understood, reducing the risk of errors in production. Utilizing the best dimensioning systems allows engineers and designers to maintain uniformity, improve communication, and streamline the manufacturing process. By adhering to these standards, industries achieve precise, reliable, and efficient results in creating high-quality components and products.
A reference dimension is a dimension that is not crucial for the effective use of the part. Reference dimensions are not inspected.A reference dimension may also be a dimension that is shown elsewhere in the drawing but is shown in the current view to help clarify the position of other features in the view. This practice eliminates "double-dimensioning" which is not acceptable in drafting standards.
It refers to "centres". When appended to a dimension it means the dimension is to / from the centre mark of a diameter / radius.
A line on a drawing pointing to another line or part to which the dimensions relate.----