I had the opportunity to make one of those shredders about 8 years ago. The two employees I had at the time and I had a blast with it before delivering it to the customer. It was stout enough to shred a metal desk chair.

Ours was modeled after the shredder that is used at the scrap yard. Each blade is razor sharp on the edges, and has a feeder tooth to help pull the material down. It is basically a shear, of scissor, if you will.

A shredder like the one we made, with a full set of spare blades, cost the customer a bit over $60K, and only took us 5 weeks to make once the material was delivered.

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1987 560SL
85,000 miles