What’s “Cavaforming?”

Armed with a 40-foot-long, 40-ton cold-forming machine that’s long been out of production, this mold manufacturer can produce tubular insert IDs with ±0.0002-inch tolerances and a 4-micron surface finish without EDM or polishing.


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You turn to Modern Machine Shop primarily for information about cutting metal, not forming it. So, you won’t find much material here on rotary swaging. Nonetheless, I think it’s worth sharing the last article I wrote for MoldMaking Technology, our sister publication, before transferring to Modern Machine Shop a few months back.

After all, metalcutting might not be all you’re interested in, and I’m guessing you’ve never seen anything like what this plastic injection mold manufacturer is doing. “Cavaform” (for “cavity forming”) isn’t just the name of this shop. It’s also the trademarked name of a rotary swaging process used to produce tubular insert IDs by forcing an annealed steel tube around a hardened mandrel. The result is ±0.0002-inch tolerances and 4-micron surface finishes right off the machine, prior to any subsequent polishing. Beyond the “cool factor,” perhaps it will spur some ideas for your own operation. 


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