HOME FAQs BOOKS JOBS: Help Wanted Suggestions you are here: Hotline/Forum => Letter 20051
Titanium watch finishing porosity, etc.
|
+++
Dear group, Over the past few years, a lot of titanium watches have been introduced on the market, ranging from Swiss to Japanese manufacturers. Although many of its merits have been hailed as being superior to stainless steel cases and bracelets, I have noticed some disturbing oddities about the titanium watch cases. In the early years of its introduction, (I'm guessing mid to late 1980's to early 1990's) it seemed as if the titanium used was softer than what is currently on the market, I am also guessing it was used in its purer form. Bracelet links used to bend faster and sometimes showed signs of fissure at stress points. I understand there has been an improvement by certain mfgrs in the coating and hardening of the titanium watch surface, the details of which I am not aware of in detail as I am not into production, but rather in their repair and restoration. My questions are twofold. 1. Why are almost all titanium watches offered in a frosty (or matte) finish? 2. What is the surface porosity of titanium watches? Especially when compared to stainless steel. Depending on the outcome of the second question, I shall be in a better position to ask a third question. Thank you kindly for your time and assistance. I hope to return the favor. Best regards, Manuel Jean- Montreal, Quebec, Canada +++ Good question. I have a partial answer. First of all, I am not familiar with the question in relationship to titanium watches. I have tried to surface finish titanium for a couple of applications and all of which were not too successful. The porosity of this metal is great, well over 35 RMS, or at least to samples I got from other sources to process. The quickest way to get a smooth finish was via an abrasive wheel system. Because of this processing time and/or labor, it seems that most processing is done with abrasive blast methods. |
|
AF Kenton Huntingdon Valley, Pennsylvania |
+++
Timing and/or labor of titanium polishing can be replaced by quick titanium electropolishing. (however surface must be mechanically prepared to the roughness of 1-2 micron)For most of the alloys (grade 1-4 and single-phase alloy) the surface will be perfect mirror reflection. Two-phase alloy produces bright surface also, however under the sun light you will see the grain structure. Our method uses electrolyte based on salts dissolved in water.
 | Anna Berkovich Russamer Lab  Pittsburgh, Pennsylvania |
|
April 12, 2011
I have been informed by a famous manufacturer of Swiss watches that the stainless steel casing of my watch has become porous over the past 25 years and must now be replaced. Is this possible?
Best regards
- United Kingdom
April 12, 2011
Hi, Brian.
"Porous" to the extent that it is difficult to keep it bright and shiny sounds believable. Porous to the extent that it's no longer waterproof or hermetically sealed sounds ludicrous.
Regards,
|
 Ted Mooney, P.E. finishing.com Brick, New Jersey |