Not sure who the original post was a victim of.... but my chain drive door opener with a BLUE casing, Branded "DoItBest" [local lumber yard chain store] had the exact same failure. I went into the lumber yard with the busted off sprocket in my hand. Their eyes rolled back in their heads and they pointed to a box on the floor. It was 90% of the parts of a brand new unit, just like mine. The box had been opened to "warranty" some part or piece of the chain rail of somebody else's Chamberlain door opener. Apparently Chamberlain contract-bulids for DoItBest. The lumber yard boys were going to claim the whole thing anyway so they said... "help yourself to the power unit and bring yours back... no charge" And so, I got a new power unit, rebalanced the door, and I'm back in business, BUT I plan to inspect that shaft from time to time.
Linear guides are one of the most important components required for the design of automated or computer-controlled equipment. Aluminum profile extrusions, used for these guides, can enable designed-in functional features.
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