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How to hard anodize the inside of a closed end shock tube the same thickness as the outside

12 inches long and closed on one end. The diameter is about 2 inches. The customer wants the part Hard Anodized. They want the inside of the tube 1 mil buildup.My question is how can I get that buildup on the inside all the way down the tube. Any help would be appreciated. I have about 1000 of these parts.

Jeff Stewart

2006

I am an owner of an anodizing shop and I have a shock tube about

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First of two simultaneous responses -- I had a limited exposure to hard anodize, but I have doubts if you will have a uniform thickness the full length of the ID. sounds like a part that will require special fixturing and an internal cathode for a quality product. I hope you have not priced it yet.

James Watts
Navarre, Florida
2006

If it is completely closed on one end, just processing it thru all of the tanks and rinses is going to be difficult as well as time consuming.

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Second of two simultaneous responses -- 2006

It will be a challenge for 1000 pieces, but the best way to accomplish this is to insert a small diameter cathode rod inside of the tube during processing, obviously being very careful that the cathode rod doesn't touch the inside of the tube.

Marc Green
anodizer - Boise, Idaho

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2006

Insert an cathode is a way though, I would prefer to block the outside of the part. Just like putting the part inside another tube which diameter has to be calculated, it would be easier practically.

John Hu