Finishing Workshop. Columbus, Ohio May 16-17, 2017

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1 Finishing Workshop Columbus, Ohio May 16-17, 2017

2 Racking Systems for Anodizing By: Ed Burlingham President & Chief Operating Officer Burlingham International, Inc.

3 General Factors in Jig and Rack Design Proper racking is a critical part of anodizing and must successfully accomplish at least three basic functions:

4 To hold the parts securely during the transfer between process tanks and while immersed in a vigorously agitated solution.

5 To provide contacts with the work that will safely conduct enough current from the source to the part to provide a uniform coating.

6 To ensure that the work can be adequately drained and rinsed, leaving no pockets of residual solution.

7 General Factors in Jig and Rack Design The following factors need to be taken into account in jig and rack design and the way in which components are secured on racks:

8 Suitability for the process sequence and solutions used.

9 Density of components must balance the economics of bath loading against the danger of local overheating and shielding.

10 The rack must be cost effective in terms of the quantity to be produced and the revenue from the job.

11 Provide enough contact points to conduct the current required and ensure a uniform coating.

12 Two Examples: Example 1): Type II Anodizing / 1 mil finish required and you have a 12,000 amp Rectifier. You will need 15 amps per square foot, therefore, you can anodize 800 square feet per load. With 800 square feet, you will need a minimum of 20 contact points at 40 amps per contact with an aluminum rack. Example 2): You have 4,000 small parts that require.30 amps for a quality finish. Therefore, you need a 1,200 amp Rectifier and 150 contact points at 8 amps per contact for the entire job if your rack material is Titanium.

13 Location of rack marks in positions acceptable to the customer and adequate for the anodizing process required.

14 Ease of loading and unloading of parts Design racks based on floor plan

15 Racking Methods Pros and Cons Following are the primary racking methods currently being utilized for the anodizing of aluminum extrusions, brake metal and related parts:

used primarily on clear Rackers can over twist Custom

16 Racking Methods: Pros & Cons Twist Pros - Speed of Racking Large Quantity Cons - Concern with good contact - used primarily on clear Rackers can over twist Custom racks with relatively short life expectancy Aluminum in waste stream

on certain parts Uniform coatings can sometimes be a problem

17 Racking Methods: Pros & Cons Stack Pros - Speed of Racking Quantity per load Cons - Difficult to rack many different shapes - only used on certain parts Uniform coatings can sometimes be a problem (shielding) - tendency to stack too many, too close Aluminum in waste stream

18 Racking Methods: Pros & Cons C Block with Bolt Pros - Speed (pneumatic tool) Good contact Do not need to strip work bar after each cycle Smaller consistent rack mark

19 Racking Methods: Pros & Cons C Block with Bolt Cons - No flexibility in rack - fixed distances Large increases in rack inventory Need, higher paid, custom rack maker - welding or bolting on spline bar. Re-tapping for larger bolts Bolts last only 3 or 4 cycles and tend to seize up Aluminum in waste stream

20 Racking Methods: Pros & Cons Wiring Pros - Very inexpensive initially Good flexibility of spacing on rack and can use as support in middle with customer okay Cons Last only 1 cycle Speed Mess in shop and racking area

loading and unloading area Rack clean up and short rack life

21 Racking Methods: Pros & Cons Welding Pros - Good contact Color consistency Cons Welding equipment and operators in loading and unloading area Rack clean up and short rack life Used on specific extrusions only lose end of extrusion Sharp edges

22 Racking Methods: Pros & Cons Plastic Clamps Pros - Flexibility Standard Spline Bar - Every rack can be made into a custom rack Speed good with learning curve Non-corrosive / Nonconductive Small consistent rack mark No aluminum in waste stream

23 Racking Methods: Pros & Cons Plastic Clamps Cons - More expensive initially calculate against number of cycles

24 Sample Cost Comparison: A. Aluminum C Block with Aluminum Bolt 1). Material: C Block = $.75/15 cycles = $.05/connection Bolt = $.68/03 cycles = $.23/connection (3/8.16 x 1-1/ Alloy) Total = $.28/connection Includes cost to extrude, cut, drill and tap block.

25 Cost Comparison: B. Plastic Clamp 1). Material: Clamp:$ 3.57/100 cycles Strip Workbar Total = $ 0.036/connection = $ 0.04 / connection = $ 0.076/connection 2). Labor: 8 sec. - Install 8 sec. - Remove

Troubleshooting of Electrolytic Color Anodizing of Aluminum

Troubleshooting of Electrolytic Color Anodizing of Aluminum Bob Srinivasan, Bob S. CONSULTING, Brookfield, Wisconsin, USA Electrolytic color anodized aluminum offers a highly durable finish for architectural