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Etching bath and procedure for titanium tubing

I have been a custom titanium bicycle builder for nearly 20 years and until now have only needed to deal with mechanical cleaning of tubes before welding.

I now have a batch of annealed 3/2.5 tubes for bicycle frames. The parts have a light oxide layer (straw to blue color, but not deep at all) on them. It is very easy to remove the oxide by hand with a Scotchbrite pad, it is not deep or stubborn. I would be content to clean them in this fashion, but the shape of the tube (swaged and ovalized) makes it difficult to mechanically clean the inside, which is necessary given that they will be welded.

I have read that nitric acid/HF baths are common for removing heavier scale, but I am concerned about the safety of such a process and I'm not sure about dealing with acquiring/storing, etc of the chemicals. Also, I need to be sure that whatever process I use does not leave anything behind that could affect the integrity of the material as it will be welded.

Is there is a simpler (safer) solution for such (relatively) light cleaning? If not, can I safely carry out this process at my shop (and if so, where should I be looking for the necessary chemicals)? I have about 100 tubes to clean, they are 18" x 1" if that matters.

Thanks in advance.

Jim Kish
Bicycle builder - San Luis Obispo, California, USA
October 14, 2008

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Hi, Jim. Because you have not previously employed wet processing, you may not be aware that there are jobshops available to process this material for you. They would have the chemicals, the safety protocols, and the experience to do the process for you if you prefer.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 14, 2008

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We can suggest our proprietary gel for titanium cleaning from oxides. This gel also contains hazardous ingredients, however gel can be applied locally by brush, and only on places that require cleaning.

There are no changes in mechanical properties of titanium after treatment.

Anna Berkovich
Russamer Lab

Pittsburgh, Pennsylvania

October 17, 2008

Thank you, do you know of a reputable place? I haven't had luck finding anything in my area, but may not be fishing in the right hole.

Jim Kish
- San Luis Obispo, California, USA
October 20, 2008

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Hi, Jim. Please re-post the particulars of the finishing service you wish to contract for in our "Looking for a Jobshop RFQs" and I'm confident you will be contacted by potential suppliers. By the particulars I mean the overall size and anticipated annual volume, and what you want them to do.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 21, 2008