When is it appropriate, you ask? The answers are more complex than the simple answers here but if you process the same parts over and over, are concerned with cost, or your customer wants specific and well placed racking, you may want to consider specialized tools. High volume is NOT the only reason to consider specialized racks/tools. I have worked with many customers to design tools that specifically address concerns they have about their parts regardless of volume. In addition, many customers are willing to pay for this to insure good quality and the lowest pricing, not to mention that it is likely to reduce their turn time at the anodizer.
Usually, specialized racks mean, titanium racks. Titanium racks have long life because they are not consumed by the chemistry and they do not need stripping after anodize. They offer repeatable quality, lower part cost and/or faster turn times but these racks/tools can be expensive.
Aluminum racks/tools must be stripped after each anodize cycle and this, as well as the anodizing itself, consumes them and therefore the part price must be reflected in this. They are also seldom a perfect fit for the part but rather adjusted or adapted to the piece. While aluminum is less expensive, it is not cheap, and usually must be discarded after several cycles. In addition, since they are not specialized enough to maximize production quantities, turn times can be longer if there is even moderate volumes.
There are thousands of specialized tools/racks designed for a variety of products and your part may be a candidate for such treatment. Cost and productivity are at stake.
This post was submitted by AAC Member Jack Tetrault, President of the Sanford Process Corporation.