1. Hardware, Fasteners, Drills, and Thread Repair
M.C.V.T.S.

2. Characteristics For the basic theory of threaded fasteners, see the
Threaded Fastener Theory Section
( 7/13/04)

3. Fastener Grades SAE: Society of Automotive Engineers
ISO: International Standards Organization

4. Fastener Grades
SAE Grade Capscrews: are evaluated by the American National Standards Institute (ANSI)
SAE Grade Capscrews: have markings to identify their strength. (Count the lines and add two.)
Example: five lines is a grade eight bolt

5. Fastener Grades
ISO: Classifies bolt quality in terms of tensile and yield strength.
ISO: Graded bolts have grading numbers on the head or cap.
ISO: Grades are given as two numbers (8.9,10.9, etc)
ISO:The first number is tensile strength
ISO:The second number is yield strength

6. Fastener Grades
Tensile Strength: is the maximum stress the material can withstand without breaking
Yield Point: is the maximum stress a material can withstand and still be able to return to its original form without damage
Ultimate Strength: is about 10 percent higher than the yield point. That is the point where the fastener breaks.

7. Fastener Grades SAE Grade Property Class
5.8
Grade 5
8.8
Grade 7
9.8
Grade 8
10.9

8. Bolt Stretch
Clamping Force: Bolts are stretched to provide a clamping force
Elastic Limit: is reached when it will no longer return to its original shape
Normally bolts are stretched to 70 percent of their elastic limit.

9. Nuts Must be matched to the bolt grade
May have grade markings on the top or sides
Grade five may not be marked
Are softer than bolts

10. Flat Washers Case Hardened: only hardened on the outside
Through-Hardened: are hardened throughout

11. Types of Washers
Flat
Lock
Shaker-Proof

12. Taps & Threads Types Taper Plug Tap Bottom
Used to start the tap into the hole
Plug Tap
Is a standard tap
Bottom
Makes threads all the way to the bottom

13. Taps & Threads SAE USS Metric Pipe
Society of Automotive Engineers (fine thread)
USS
United States Standard (coarse thread)
Metric
Several Thread Types
Pipe
Uses Tapered threads

14. Dies Are used to make external threads
Can be used to repair damaged threads

15. More Information

16. Barnhill Bolt Co., Inc.  Fastener Vendor with FAQ sheet for general info. The Nutty Company, Inc.  Fastener Vendor with Extensive Online Catalog (and a sense of Humor) Hayes Bolt & Supply Company Alloy Fasteners, Inc.  A manufacturer, distributor, and importer of stainless steel fasteners. AROW Components and Fasteners, Inc.  Fastener Vender with lots of nifty technical information on general Fasteners

17. Assignments Chap. 6 Automotive Service Review Questions Pg 66
Chap. 6 Automotive Service Workbook
Using the google search engine find information on SAE and ISO