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Braze training can make a tremendous difference in the quality of the operation. To See more articles on Brazing, visit Brazing Index page.

Deliverables on Previous Projects

1. Eliminate tungsten carbide breakage entirely

2. Reduce tungsten carbide braze failure to six sigma (3 parts per million)

3. Eliminate rework

4. Improve bond strength by 40% eliminating braze failure

5. Double tool run time

6. Increase coolant life from 2 weeks to six months

7. Eliminate safety and health risks due to Cadmium

8. Reduce safety and health risks due to Cobalt

9. Reduce costs of labor and materials by 60%

10. Smoother finishes

11. More precise cutting

12. Brazing Program Impacts

13. Cost reduction

14. Cross-functional team building

15. Greater tool reliability

16. Safety and health

17. Environmental

Brazing Program Requirements

1. Cross functional teams: Interdisciplinary, Interfunctional, and Concurrent engineering

2. Hard Data - Numbers

3. Prints and specifications for tool bodies

4. Tool performance data

5. Comparison of good to bad tools

6. Tool running instructions

7. Employee commitment to change

8. Employee ability to change

9. Management buy-in

10. Analyze current data

The topics covered are as follows:

1.       Safety and health

2.       Physics of brazed tools

3.       Braze alloy chemistry

4.       Differences in brazing alloys

5.       Parts cleanliness in brazing

6.       Braze joint clearance - Designing braze joints for tensile strength

7.       Designing braze joints for impact protection

8.       Temperature control

9.       Using SPC in brazing

• Determining what to measure

• Establishing upper and lower SPC standards

• Establishing production floor testing 

• Incorporating SPC in the production process

10.   Identifying braze failure

• Compiling braze failure data

• Analyzing braze failure from data

11.   Tool tipping materials - Tungsten carbide grades, uses and selection

12.   Grinding operations as related to brazed tools

13.  Identifying improved tool performance

• Gross breakage

• Microfracturing

• Measuring run life

14.   Quality procedures

• Establishing inspection points

• Establishing inspection parameters

• Documentation 

• Standardizing procedures

• Establishing written procedures

Special emphasis on:

1. Temperature

2. Most common causes of braze failure in order.

3. Wrong Braze alloy is the major reason for breakage and loss

4. Improper fluxing

5. Switching from Black Flux to White Flux can cause tip loss.

6. Watery Flux  

7. Dried or old flux 

8. Improper braze joint thickness

9. Too thin a braze joint

10. Uneven solder – poor tip placement

11. Uneven solder – poor wiping motion

12. Tip placement

13. Improper cleaning

14. Improper brazing temperature

15. Underheating the solder

16. Overheating the solder

17. Colors in the solder – burnt solder can have a green or pink/rose color to it

18. Gas entrapment

19. Wrong flux

20. Underheating

21. Overheating

22. Surface condition of the tip

23. Overheated tungsten carbide

24. A combination of things 

SPC Considerations in Braze Failure

Engineering sets a needed specification for brazing of 100

We set the SPC limits from 110 to 130

The system is engineered to deliver 150 when everything runs right but we only need 100.

1. For impact

2. Fluxing 

3. Heating

4. Part movement during brazing

Example

1. If everything works right we get a value of 150 and we need 100

2. If one part is at 90% we get 90% of 150 which is 135.  We need 100 and we are good 

3. If 2 parts are at 90% then we get 90% of 90% which is 81%.  81% or 150 is 121.50 and we are good.

4. 3 parts at 90% is 72.9% of 150 which is 109.35

5. 4 parts is 65.6% of 150 = 98.4 and we have tool failure 

Brazers in saw mills

1.  Inspect incoming tool bodies (saws, shapers, routers, band saw, planer knives, etc.,)

2.  Accept or reject the bodies

3.  Repair bodies

• Tension

• Flatness

• Cracks 

• Wear

4.  Resurface body before brazing

5.  Specify tool tip material

6.  Clean tool tip material

7.  Flux

8.  Braze

9.  Inspect

10.  Track tool performance

11.  Track each tool individually

12.  Specify tool design and re-design

13.  Maintain equipment 

• Sun Studs article in Timber Processing magazine

• Exact placement of induction heating

• Computer controlled brazer

• Digital feedback screen

• Video inspection system

Critical Points

1.  Tools

1. All tools are inspected against original specifications

2. All tools are brought back to original specs before re-use

3. Within one half thousandth 0.0005”

4. Fit and flatness – Darryl’s question about gaps

   • Ribbon is flat

   • Tungsten carbide is flat

5. If body is flat then flux and dirt are only possible source of problems

2.  Material selection

Different materials used depending on task to be done 

3.  Heating

1. Calculated, measured, preset exact heating

2. Tungsten carbide position +/- 0.001” / 0.002”

3. Black Flux

4. Video inspection system

5. Calibration marks

6. No Cadmium 

4.  Tungsten carbide grinding

1. Precision automatic machines

   • CNC

   • “Screw” type

   • Cam controlled

2. All hydraulic

3. All flutes ground exactly equally 

5.  Records

1. Records kept of each tool by serial number

2. Every tool has a computerized history 

6.  Equipment maintenance

1. Serviced and checked daily

2. Also weekly and monthly

3. Annual total rebuild 

7.  Performance

1. In the cut saw monitoring systems

2. Amperage draws to determine edge condition

3. Specified run-times for tools

4. 2.5 hours for band saws

5. 5 hours for round saws 

Recommendations

1.  Start keeping records

• Measure what you think might be important to see if it really is. 

• Add or delete recording keeping as it seems important 

2.  Get original specifications where available

3.  Test to see if those specifications are still valid

4.  Do not use out of spec parts and materials

You can make good tools out of bad parts sometimes but the odds are against you.

5.  Same with equipment

• Find out how the equipment is supposed to perform.

• Figure out or find out how to test to see if it is performing properly.

6.  Set upper and lower limits for acceptable performance everywhere:

Roughly:

Upper limits that are too high mean too much expense, Lower limits too low mean tool failure

7.  Figure out easy, simple plant floor measurements for performance

8.  Some tools are bad – eliminate those – you may not know why but the record will show that some break more than others

9.  Compare good tools to bad tools every way you can

Test to see which differences are important

10. Work with other people in other departments

• Brazing Program Impacts

• Cost reduction

• Cross-functional team building

• Greater tool reliability

• Safety and health

• Environmental