Question

1. Each datum feature on a part requiring identification must be assigned a different datum identification letter.                                                                                                              
   
   TRUE/FALSE

2. A datum is a point, axis, line, or plane consistent with or resulting from processing or inspection equipment.                                                                                                                
   
   TRUE/FALSE

3. What is the difference between a Datum and a Datum Feature?

a) A Datum and Datum Feature are synonymous.

b) A Datum is theoretical, a Datum Feature is real.

c) A Datum is a feature of size, and a Datum Feature is a surface feature.

d) A Datum Feature is theoretical, and a Datum is real.

4. Datums should be assigned base on..?

a) How the part is inspected.

b) How the part is manufactured

c) How the part is assembled

d) How the part functions.

5. What is the 3-2-1 rule?
   1. You must have 3 primary datums, 2 secondary datums, and 1 tertiary datum?
   2. You restrict 3, then 2, then 1 degree of freedom for each datum you add?
   3. You must have 1 point of contact for a primary datum, 2 for a secondary, and 3 for a tertiary
   4. You must have 3 points of contact for a primary datum, 2 for a secondary, and 1 for a tertiary
      

How many degrees of freedom are there?

Answer 1

Answer-1 True

Each datum feature on a part requiring identification must be assigned a different datum identification letter.    

Answer -2 True

A datum is a point, axis, line, or plane consistent with or resulting from processing or inspection equipment like surface plate, inspection table or a mandrel.

Answer-3 b) A Datum is theoretical, a Datum Feature is real.

Answer-4 d) How the part functions.

As per ASME standard Datums should be functional.

Answer-5d) You must have 3 points of contact for a primary datum, 2 for a secondary, and 1 for a tertiary. This is 3-2-1 rule.

Plz rate!