Aluminum-Bronze

[Greg_Lewis]

Praise be to search engines:

http://www.superiorflux.com/aluminum_br ... _flux.html

[Glenn Brooks]

Yikes, with Military markup, it is $187,000 per ounce.

[Dick_Morris]

Or $25.45 per pound. Take your pick. http://www.sra-solder.com/aluminum-bron ... fgodCqgDSQ

[Greg_Lewis]

And if you buy through Amazon, you can get 2-day shipping.

[Bill Shields]

thanks to all for the advice

[Rwilliams]

I agree with Jack Bodenmann, the AL Bronze definitely requires ultra sharp tools when being cut. A diamond hone is your best friend when sharpening a lathe tool for the material. Files also have to be like new or will simply slide across the surface.

I needed to make new spindles for full size steam locomotive injector supply valves connected to the turret casting. The area where the packing contacts the smooth spindle in the packing nut/gland area needed to be super smooth for the packing to not wear out too soon. Even with a sharp round nose tool, the finish was still a bit less than what I wanted and the file only improved the surface finish slightly. Out of desperation, I grabbed a small aluminum oxide bench stone with a fine grit. Applied some sulfur based cutting oil to the surface in question and went after the new spindle with light cutting pressure on the stone held in my hand. It was amazing how nicely the stone cut away the small high spots on the new spindle. Kept the stone moving constantly almost like an external hone until the deed was done.

I had done extensive honing on a Sunnen pin hone in the past on internal bushings. That experience with stones on bronze is what encouraged me to use the external stone treatment on the valve spindles. In all I made 5 new spindles and refinished the main turret stop valve before the valve rebuild adventure was done. I used the stone treatment on all of the spindles after the first one came out so well. After than experience I have never looked at a bench stone the same way again. Since that point in time, I have used the bench stone on more projects and materials in the lathe and have had nothing but great results in less time. Just wish I had considered this option long ago.

I have never seen anything in any machine tool text book on using stones to smooth up lathe cut surfaces. Only once have I seen a stone used in a watchmaker demo in a You Tube video. In that case, a sharp inside corner was being finished with a nice little square stone. Sometimes the immediate need of the situation forces us to go beyond never knowing for sure what the result might be but, the result might be for the best. I advise you test the method on a test part to gain a feel for what can be done with a stone in the lathe.