This information is from my blog: shopsmith-tool-hunter.blogspot.com/
The Joint-Matic was originally sold by the Strong Tool Company as the Strong Jointmatic and after Shopsmith purchased the rights to make it they took it into their R&D department and added dust collection and removed one lead-screw and the synchronizing bicycle chain. After a few years this tool was retired. There is one important thing that you need to keep an eye out for if you are shopping for the Shopsmith version of this tool. You'll want to make sure that the plastic platen that moves the router up and down isn't cracked where the knob that adjusts the backlash out of the lead-thread, threads into the platen. If you are buying one online ask the seller to tighten the knob gently and snap a photo of this detail from above. It it's cracked, take a pass.
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