About Us

Our Story

Terra Diamond and GDM were each founded to create the products cutting and coring companies needed. As the years have passed, innovation and quality craftsmanship shine through, keeping both Terra Diamond and GDM at the forefront of the industry.


Al Schuman with his first saw.

In 1963, Al Schuman started GDM Equipment after designing the first track-mounted wall saw. Using straightforward design and quality materials, GDM became known for reliable, user-friendly equipment without compromise.

Pat O’Day testing saw blades - 1975Pat O’Day testing saw blades – 1975

Terra Diamond began in 1978 with Pat O’Day, who set out to build a company that specializes in manufacturing diamond blades, bits, and grinding products of the highest quality.

For over half a century, we have built high-quality diamond tools and equipment that we are proud to say are MADE IN THE USA.

With decades of manufacturing experience, we build the tools needed to get the job done. We work in the tradition of our founders to get the product to our customers the way they need it, on time, with an uncompromised level of service.

WHEN YOU NEED US, WE’LL BE THERE.