For Cost Reduction
Dimensional Tolerance Design Pointers for
Cost Reduction

FOLLOW THESE SIMPLE SUGGESTIONS
TO HELP MINIMIZE THE COST OF YOUR
CERAMIC COMPONENT
DESIGNATE MODERATE "AS-FIRED" TOLERANCES ON PORTIONS OR
FEATURES THAT ARE NOT CRITICAL

INCERCO manufactures a variety of ceramic components that are used in a variety of
applications and industries.  Unique process technology is applied to manufacture these
components in which green (unfired) bodies are formed from raw materials and are then
machined, fired and then can be diamond ground and machined.  Because the only material
harder than ceramic is diamond, post sintering processing of ceramics can be relatively
expensive because of the use of diamond grinding wheels and slurries, etc.

The most economical ceramic component you can design is one that uses "AS-FIRED"
conditions and tolerances.  You can minimize the cost of your ceramic component by
allowing +/- 1% of a linear dimension as its tolerance (or +/- .005" whichever is greater).  If
you can't use +/- 1%, as a tolerance, review your design to see what you could use.  In
some cases, we can control our AS-FIRED tolerance to less than a half of one percent.

CONCENTRICITY

Allow for .010" T.I.R. on parts that are "AS-FIRED".  On ground components, .005" T.I.R. is
the least expensive.  On precision parts that have to be concentric, .001" is the cheapest.  
Usually when we O.D. grind, we will be in the .0002" / .0003" ballpark.  Concentricity of 1
tenth or 50 millionths require added cost and special operations.

FLATNESS OR CAMBER

Flatness (Camber) should be noted as .006" of an inch...per inch.

SURFACE FINISH

The AS-FIRED surface should be specified to have a 63 microinch surface finish max.  If
you have a dimension that you have to have ground and polished, a 10 to 14 microinch
surface finish is normal.  A 2 to 4 microinch surface finish is the most expensive.

CAN YOU LEND US YOUR SAMPLE?

If you are considering changing an existing component to ceramic, we can make
suggestions about tolerances, shapes, features, etc.  if we can borrow a sample you have
been working with so far.

CALL US

When you call INCERCO, you can talk with an experienced professional who has the
answers to the questions you'll be asking.  With our company, you won't get stuck with a
customer service person or with a salesman who has no manufacturing or materials
expertise.  You can talk to a seasoned professional and get real answers and if we can't
help you, we will point you in the right direction to go.