Themac produces a series of grinding machines that are designed to be mounted on any make of bench or engine lathe. The Themac tool post grinder is accepted as the standard in the American industry and maintains its own niche in the market today.

The company was founded in 1936 by Err McGonegal as The McGonegal Manufacturing Company. Mr. McGonegal was a Scot who had a canny sense of business and the skill to produce a precision tool that would be in demand for decades.

After a few decades, the company was then stewarded for over 40 years by Joe Cremona who was loved by family, friends and business associates.  Mr. Cremona built on the success of Mr. McGonegal by improving the design of the product line and streamlining operations.

In the summer of 2017, the business was purchased by the Illian family who is dedicated to continuing the rich tradition of manufacturing high-quality grinders in the USA. With experience in running a machine shop, Norm Illian wants to continue producing the best tool post grinders in their Northern New Jersey facility and provide support for existing grinders.

Even though the business has had different ownership: The McGonegal Manufacturing Company, Themac Inc and now Themac LLC, the commitment to quality, service and integrity has never changed.