Eastern Power Equipment
285 Route 9 PO Box 97 Barrington, NH 03825
Phone 603/664-7776 | Toll Free 866/664-7776 | Fax 603/664-7420 | email chuck@easternpowerequipment.com
Prepare concrete surfaces for repair
It’s smooth sailing when you put a concrete grinder to the task
The first step in repairing and resurfacing concrete floors and other paved areas is to prepare the surfaces properly so that new overlays or coatings can bond securely. To do the job right, consult your A.R.A.-affiliated rental professional to secure the proper rental equipment and knowledge for your particular application.
What grinders accomplish
All grinding disks use friction in one of two forms:
- To cut surface irregularities with an action similar to that of a saw blade
- To scrape surfaces using an attachment that penetrates the material and shears material from the surface
Concrete grinders’ horizontally rotating cutting disks clean and smooth concrete surfaces. They are designed to:
- Work on the top surfaces of large areas of concrete to remove old sealers, mastics, epoxy, urethane, paint, other coating materials and carpet backing
- Clean buildup of industrial residues such as rubber, grease and fiberglass
- Level high spots and uneven joints, generally when irregularity is no more than 1/16 inch
Grinder types
Grinders cut and grind with one or more horizontally rotating disks. These disks feature imbedded inserts, which typically contain a variety of abrasive media, including industrial diamond chips, tungsten-carbide pellets, silicon carbide plugs, cutting stones and brushes.
Hand-held grinders accomplish small jobs, like edge work. In general, dual-head, walk-behind and dolly models are the most preferred rental machines.
Types of grinders available include:
- Single- or multiple-head designs – Multiple-head designs have two, three or four cutting heads. Counter-rotating disks prevent these machines from pulling from side to side during operation, making them easier to control
- Electric-, gasoline- or propane-powered models
- Small, single-head, hand-held models
- Walk-behind units with single or multiple heads
- Large dolly-mounted, multiple-head machines
- Dust-free models that collect fine dust generated from the grinding process. Some models are designed to use water
Choosing the right grinder for the job
Count on your A.R.A.-affiliated rental professional to help you choose the right grinder for the job, and to provide training on grinding accessory installation, machine operation and speed control. Be sure to get the right grinder for the specific job. Before renting, let your rental pro know:
- Surface type
- Material to be removed
- Material thickness
- How long coatings have been in place
- Material condition, i.e., solid, flaking
- Total surface area of the project
- Whether conditions will be dusty
- Existing power source
Grinder dos and don’ts
Grinding machines are powerful pieces of equipment. Address these safety and operational procedures before use in any area.
- Never operate gasoline-powered grinders in unventilated areas.
- Use only properly sized, grounded electrical cords on electric grinder models. Be sure power sources are adequate for the machine size.
- Know your concrete’s psi rating. The type cup, disk or cutters needed depends on the hardness of the surface. Be aware, concrete hardens as it ages, and varies by region of the country.
- Wear safety shoes, gloves, and ear and eye protection.
- Properly ventilate inside projects.
- Dust may contain asbestos, silica or other dangerous materials. OSHA may require wearing masks or respirators.
The right accessories
In addition to renting a grinder, grinding accessories, diamond inserts and stripping accessories are available for rent and/or purchase.
- Diamond grinding accessories -- with or without water -- accomplish the majority of grinding jobs. Grinding disks rotate from 300 to 2,300 rpm – the higher the rpm and the greater the weight of the machine, the faster the cutting actions will be.
- If dust is a problem, rent a vacuum system.
- Most A.R.A.-affiliated rental stores sell stones, scarifers and wire brushes.
- Protective equipment, including gloves, and breathing, hearing and eye protection are available, too. These are highly recommended when using a grinder.
- Depending on the job, you may need other equipment for surface preparation. Discuss your options with your A.R.A.-affiliated rental expert.