ED-1 course- Notes Types

what is the need for drawing Notes?the need for drawing notes is as follows:

it provides information that clarifies the requirements for the item delineated. They apply to either a portion of the drawing or to the entire drawing providing additional treatment, finish, protection, and other considerations. 

The Notes area of a drawing shall be identified with the heading “NOTES” see fig.1

fig.1

what are the main types of drawing notes?the main types of drawing notes are as follows:

1. Dimensions notes
2. General Dimensional Tolerance Notes 
3. Informational Notes 
4. Security classification notes
5. Miscellaneous notes

1- Dimension Notes 

the best drawing is the fully detailed the fully dimensioned drawing , so for writng the dimensions units on every dimensioned segment for a fully deatilled drawing will take a space that must be applied to show the details itself and we can substitute this by writing general dimensions notes like the following:

• Dimensions are in millimeters ( or other length unit) . 
• All dimensions apply  after surface treatment. 
• Dimensional limits and surface roughness. 
• Dimensioning and  tolerancing  to be interpreted in accordance with ....( specify applicable standard or code).

2- General Dimensional Tolerance Notes 
The general tolerances entered in the supplementary portion of the Title block shall control all dimensions applied to the drawing, except those specifically labeled “Max,” “Min,” “Ref,” “Datum,” or “Basic,” or dimensions having tolerances applied directly thereto, or dimensions controlled by notes or documents invoked on the drawing. 

General tolerances may be changed to the prevalent tolerances that are required by the drawing type. This is done by striking through the tolerance and inserting the new tolerance beneath the old. and we will come back to these notes type latter.

3- Informational Notes 

these types of notes is included in drawing to show detailed information rather than technical ones.

Informational notes, such as the following government rights to manufacture note, shall appear adjacent to the right border and Title block of the drawing: 

The Xxxx Company, Chicago, Il., Part

Number Xxxx Corresponds To The Item Depicted On This Drawing, Which Is Furnished For Unrestricted Use In Connection With (specify standard ,code, Authority ) Manufacture Or Procurement.

Such Use Is Authorized By The Xxx Company Letter No. Xxx Signed And Dated at ..... No Other Use Is Authorized.

4- Security Classification Notes
The security classification will take the following forms according to the security classification of the drawings :

• “Top Secret,”
• “Secret,” 
• “Confidential”
• “Confidential but not classified”
• "Not Classified"

 the security notes shall be located on the drawing as noted in fig.2 

fig.2

Each sheet of a multi-sheet drawing shall be individually classified as to its contents. The security stamp on each sheet shall be that of the highest classification for any item shown on that individual sheet, not the general overall classification of the entire set of drawings or the end item. 

On roll-size drawings, the security classification shall be shown on the reverse side at both ends of the drawings next to the drawing number to enable the classification to be seen without unrolling the drawing. 

5- Miscellaneous Notes 

there are a lot of Miscellaneous Notes can be used in showing special information in drawings as follows

• Altered Part Source Information: 

1. Part No.:
2. Vendor:
3. Address: 

• This Drawing To Be Interpreted In Accordance With (specify standard, code, another drawings or specification)
• A Manufacturer's Certification Of Material Specification Compliance Must Be Supplied With Part ( specify the material part #)
• Components Must Be Packaged And Marked In Accordance With ( specify standard or code)
• Shipment Shall Be Made Directly To The Using Agency. Explosive Components Are Hazardous And Must Be Handled In Accordance With Applicable Safety Regulation