may have built the next best thing to a better mousetrap-a mini-grader that squeezes through narrow doors but does a big grader job.And although the world hasn't yet beaten a path to his
says so many contractors are hiring his
machine that he's
building another one.The machine is an articulated, hydrostatically-driven motor grader which measures a mere 11 feet long, four feet wide and four feet high, and comes with a six-foot moldboard and five-foot dozer blade.It fits through a five-feet four-inch doorway, but can fine-grade a gravel sub- grade at the rate of 25,000 sf a day with laser-assisted precision.In fact, that's what he
six-month-old Plaistow, NH firm-Precision Grading Company
.Grading inside buildings and other tight spots is his
saw a need for a long time ago."I've been operating heavy equipment and working in construction for twenty-two years," he
said, "and I know from experience what a pain it is for contractors to have to fine-grade the gravel by hand before they pour the concrete floor."I got the idea for the machine seven years ago, and it took me almost that long to perfect it.I actually torched the thing seven times, right back down to the tires, before I got it right" He
said the next one should only take him a month to build, now that he's
got the design perfected.Paradis
built the machine right from scratch.It features an 18-hp Cushman golf cart gasoline engine which powers a Vickers six-gailon oil pump and which in turn drives the Charlin hydraulic motor -the primary mover for the entire hydraulic system.Because of the hydrostatic drive and the gearing he
said the 18 hp is actually boosted to 119 wheel horsepower, giving him all the power and infinite speed he
needs for the job.The sixlever hydraulic controls raise and lower the dozer blade, raise and lower the moldboard, move it laterally and vary the angle of the blade.The moldboard itself is made from a ten-inch-diameter steel pipe, while the cutting blade is a standard manufacturer's piece.Giving him the precision and production he
said, is the SpectraPhysics ELI Electronic Level he
bought from Waste, Inc.
of Concord, N.H.The level provides an invisible electronic signal which is picked up by a target sensor mounted on the grader's moldboard.Set up above the grader's hydraulic controls, and wired to the target sensor, is a remote display which tells Paradis
blade is too high, too low, or on target for the predetermined grade."When I first started using the minigrader," he
said, "I didn't have the electronic level.I was able to fine grade about 12,000 square feet a day."Now I can do about 25,000 square feet a day-and I can do it to within a sixteenth of an inch. "Leo Paradis of Precision Grading uses his homemade mini-grader to fine-grade the gravel base for a concrete floor in a commercial building.
At left is the Spectra-Physics Electronic Level which he
uses to guide the grader's moldboard during the precision leveling operation.
The grader is so small that Leo Paradis hauls it around on the back of his
pickup truck, yet he
grades up to 25,000 square feet of floor slabs a day with the miniature machine he
designed and built after getting the basic idea for it seven years ago.