Brass Gears and Titanium

[Chubtoad]

Does anyone know of any problems with making gears out of brass or bronze (such as being too soft, not being able to take the pressure, etc.)

Also, does anyone know if you need anything special to cut Titanium on a regular Lathe?
Thanks

[Joe Johnson]

Brass is a very good gear material.

The yield stress of many brasses is higher than that of many steels. Also the wear & friction properties are often better than steels.

Depends on the particular alloy & processing.

In general brass is a great material (expensive compared to steel, but good just the same.

Can't help you on lathing titanium. By the way, I recall trying to save weight in past years by using titanium. The problem we had was that not all titanium is created equal. The titanium that is available from small parts inc is not the top grade. Our investigation predicted that for the same strength, the titanium in the SPI catalog would weigh MORE than what we were trying to replace. FYI.

Joe J.

[dlavery]

You can turn titanium on a small home lathe. I have done it on mine (12x36" Enco). Use a slow cutting speed (around 20 feet per minute for high speed steel cutting tools, up to 100 fpm for carbide tools) and relatively high feed rate (>20 mils/cut minimum). And use lots of coolant while you cut.

I tried it for the first time right after the competition last year, making a friend's wedding ring. I was worried about all the "mystery" of working with titanium, but it turned out to be very easy. It cuts and finishes very nicely, and seemed easier to work with than a lot of steels. Have fun!

-dave

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All opinions expressed herein are the result of too much time with too little to do.

[Chubtoad]

Thank you both very much, thats exactly what we needed to know.
-Much thanks from team 271