The Nesting Problem

Q: Our plating shop plates many small parts in barrels. Many of the parts tend to stick together or nest. How can we minimize this problem? Are there any sure-fire methods to minimize this problem? S.D.

 

A: I have received a number of e-mails on this topic in the last few months, so it may be worthwhile to reprint an answer I gave to this question a number of years ago: I wish I had a new and better way of solving this age-old problem-I don't. However, here are a few ideas that should help minimize it.

1. Redesign the parts. By changing the shape of the parts you can design parts that will not nest. This solution is probably the best one but also is the least likely-it's not very realistic to expect a customer to redesign parts just because the plating shop is having problems with the plating. However, if your company has control of the engineering process, this can be done.
2. Reduce the rotation speed of the barrel and the size of the loads. These two factors tend to interact with each other. You will have to experiment with these two variables.
3. Mix different shaped parts together. This approach can be very effective in reducing nesting.A variant of this is to mix "inert" materials with your load of parts. You can purchase copper-plated balls of different sizes to mix with the parts you are plating. There is one drawback to this strategy: You have to separate the parts when the finishing process is completed. It can be done manually or in some case using screens. A supplier is listed in the Products Finishing Directory & Technology Guide, 2009 edition, under Barrel Plating Media, or go to PFOnline.com and search the supplier database.