Smaller flex-shaft grinders like Foredom products and many other brands are very popular in the U.S. I use them for small-scale metalsmithing. They are generally considered more "professional" or heavy-duty than an electric rotary tool like a Dremel, which is mainly marketed for "hobbyists." Then there are pneumatic die grinders, which I use often for grinding/polishing on larger metal and concrete projects.

I have worked briefly in a factory where we had larger flexible shaft grinders with powerful 2-5HP, variable speed motors. They seemed fairly old and used, but worked great. I have been looking for one for my shop, since I think in many situations I would prefer using that over an air tool/die grinder. But I am finding that there are not many options in the US for these tools. New they are very expensive and used they are very rare. I have asked a few people about them and to my surprise most had no idea what I was talking about beyond a small Foredom-type flex-shaft tools. They seem to be more popular in other countries in Europe and Asia. They are even rare on industrial surplus and auction sites.

Does anyone know why these tools are not more popular here? And do you have any suggestions on where to find a good, used one? Brands you recommend? etc.

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