Steve Johnson


Maintenance Manager, Performance Sheets Co.
City of Industry, California

Subject: MD 410 Core Chucks from Advanced Mech. Devices, LLC (core-chuck.com)

My Professional Experience: I have maintained equipment in corrugating plants for over thirty years, mostly for Smurfit Stone in Fresno, California.

Chuck Problems: When Smurfit Stone began testing better chucks, we were using 4 inch Double E torque activated chucks and Serco rollstand activated chucks. The Double E chucks needed frequent repairs and their performance was unreliable. They often failed to grip, causing core burn-outs with downtime and they often locked up in spent cores or butt rolls. The Serco chucks also required repairs and they tore out cores. The operators preferred Serco which had fewer release problems so we decided to replace the Double E chucks with Serco.

Upgrade: In early 2001, I was contacted by Harry Hope, a core chuck expert who sold me a pair of prototype second generation roller action torque chucks. He asked me to take one apart to see the design improvements. I was very impressed with how rugged the new chucks were. They are modern devices with good old fashioned brick outhouse durability. The very rugged design prevents mechanism damage and thus solves the grip and release problems we experienced with the first generation chucks (Double E). The prototype chucks worked great, so we decided to replace all our Double E and Serco chucks with the new design. In 2003, the first production chucks (MD 410), refined with patented features, were available. We bought a pair from the first run and more later. About 4 1/2 years after service of the prototypes began, Mr. Hope advised me to disassemble one for inspection. I saw desirable "break-in" from the roller action which burnishes the expansion profiles smooth, but I saw no damaging wear or deformation. The bottom line is that all of the new generation chucks performed reliably and none of the chucks needed repairs, not even the prototypes which ran on our double backer for well over five years when the corrugator was decommissioned. I suspect that the chucks are still serving Smurfit Stone but I do not know where.

Chuck Value: I suggest that you look up the website of Advanced Mechanical Devices, LLC (core-chuck.com) to learn about the MD 410. The thicker rollers prevent denting and the longer jaws prevent core burn-out. The longer jaws do not add length to the chuck so rollstand width problems are avoided. Unlike the first generation chuck which has separate designs for 4 inch and 100 mm cores, the MD 410 combines the expansion ranges of the two old design chucks. The chuck cost was easy to justify due to the cost of downtime we saved. The rollstand operators of course appreciated the solution to chuck problems and our mechanics had better things to do than fix chucks. The long service life is demonstrated by a 30 month warranty. I recommend the USA made MD 410 chuck from Advanced Mechanical Devices, LLC to any plant having chuck repair and/or chuck performance problems.