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Anodizing cast bronze cymbals

Hello,Ted-

Nice site you've got here!

I have a question regarding the potential use of anodizing with musical instrument cymbals. For several years now I have been engaged in "blanks" that I hammer and lathe to have my sounds.

These are made of a bronze alloy called B-20...80% copper,20% tin.They are hot rolled from cast ingots in a multi-directional method that maximizes tensile and ductile strength.They are then circle-sheared and pressed into their convex shape,before annealing (1400 F,water quench). They are re-heated as many as 15 times prior to annealing,and develop a very hard surface "crust" that serves to mechanically support the softer layers beneath. This "raw blank" ranges dimensionally from 6"-24" diameter and .060"-.120" thickness. At this stage they offer little musicality...they must be "tuned". This is done by hammering and lathing. Hammering puts numerous areas of vibrational obstruction in the metal that,depending on patterned location,guides and controls the vibrations to produce desired sonic characteristics. Lathing creates grooves(pathways)for vibration to follow...another means of sound control. Here's where it gets tricky... Lathing (as removal of the hard crust) compromises the mechanical properties of the surface tension,often virtually eliminating the harder layer,leaving only soft core metal,which is not musical.Stick response suffers,the cymbal is "slow" to respond,sustain is shortened,tones cannot reach their harmonic potential,etc. In such a thin plate, Most of the musical vibration occurs at the surface,which the lathe partially destroys. I am looking at anodizing as a means of restoring the surface integrity after all other processes are complete. One of the largest cymbal manufacturers did this back in the 80's,but only in wild colors as a visual appeal,which was obviously short-lived.These days I cannot find anyone who anodizes anything but aluminum.I don't want colors,preferring the clear beauty of natural bronze.

I would very much like to have your thoughts on this endeavor...I'm not even sure if I'm looking for another related process. I am located on Duquesne Blvd, just down the street, so I could provide you with samples if necessary.

Thanks for your consideration in this matter,

Mike S [last name deleted for privacy by Editor]
- Brick, New Jersey
2003

Hello, Mike. Like all readers you are certainly invited to stop in and say hello to the crew of finishing.com.

Brass cannot be anodized. You could have it electroplated, or electroless nickel plated for hardness; but whether the very thin layer of plating would offer the right sound, I don't know. After the hard plating you could replate it with gold or brass if the chrome-like color of the nickel is objectionable.

letter 21483is also about cymbals.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003