Concrete Surface Preparation FAQs

Before starting, push down on the handle just enough to release pressure from the grinding disc. Do not lift the disc from the slab surface. The slight weight shift will aid the motor in reaching operating speed without an excessive start-up current draw.

To start the motor, switch to the “Start” position in the motor starter box. Once the motor reaches operational speed, allow the grinder to settle down to the slab and begin grinding.

Grinder Wheel Carriage Positioning
The grinder has two wheel positions — one for grinding and one for transport. When the wheels are in the forward most position, this is the transport mode. Do not grind in this position. Grinding in this position will cause damage to the accessories. Grind only with wheels in the rear position.

• The grinder should always be moved in a side to side motion when grinding. By doing so, you eliminate many of the swirl marks that are created.
• Weight helps with the grinding process as it allows the accessories better contact with the surface. The single-disc grinder’s max weight is 50 lbs for the electric model and 100 lbs. for the gasoline model. The dual-disc grinder’s max weight is 100 lbs. for the electric model and 200 lbs. for the gasoline model.
• The grinder is designed for wet or dry grinding.
• Dry grinding is preferable because the accessories constantly are in contact with the surface.
• EDCO grinders are equipped (standard) with a 2″ or 3″ vacuum port (depending on the model). Always use a high volume industrial vacuum with a grinder to control the large volume of airborne dust when grinding dry.
• When wet grinding, water is only needed to control dust and does not act as a coolant. Lightly dampen the floor or use a fine mist to control dust. Excess water will only create clean up problems.

Dyma-Serts

Dyma Serts are diamond segments welded to a backing plate to improve grinding speed and remove tough coatings.

Dyma-Serts grind 5 times faster than grinding stones and last longer – up to 30,000 square feet (2,800 sq. m.) of grinding action on standard 3,500 PSI concrete. Dyma-Serts can be used for wet or dry grinding.

Serts can be used for wet or dry grinding.

Ideal for:

• Smoothing rough surfaces or trowel marks
• Grinding terrazo
• Repairing surface damage to concrete slabs
• Removing urethane or epoxy thincoats
• Grinding sharp aggregates such as flint and granite
• Removing surface imperfections from epoxy mortars
• Leveling high spots
• Removing thin mastics and thin-set

Strip-Serts

Strip-Serts are carbide tipped blocks designed to clean floors without grinding into the concrete.

Strip-Serts have a replaceable, multi-sided tungsten carbide edge that can be rotated for maximum use.

Ideal for:

• Removing mastics, paints, resins, tar and fiberglass
• Removing ice and industrial buildups

Strip-Serts are designed to strip away coatings not to grind concrete. Grinding concrete with Strip Serts will dull the sharp edges quickly causing the grinding action to stop.

Scarifier Assemblies

Steel Cutters
Scarifier Assemblies are high carbon steel cutter assemblies in steel cases.
– Standard cutters last 3 to 6 hours
– Heavy-duty cutters last 8 to 12 hours

Ideal for:

• Breaking up hard surfaced deposits of oil-dri, fiberglass, grout or plaster
• Removing concrete buildup
• Leveling brick or wood block floors
• Initial grinding of rough, broom-finished concrete
• Preparing surfaces for overlayments
• Texturing slippery floors

Grinding Stones

Grinding Stones have various grits for course or fine polishing.

Ideal for:

• Removing trowel marks
• Removing rain spots
• Leveling high joints less than 1/16″ high
• Removing excess concrete
• Smoothing rough finishes
• Grinding and marble

Surfacer Disc Assembly

The Surfacer Disc assembly is easily assembled for heavy-duty surface build-up removal. The cutter wheels can be positioned to meet removal needs.

Ideal for:

• Removal of industrial build-ups, tar, rubber, fiberglass, grout or plaster
• Roughening concrete
• Grinding asphalt

Wire Brushes

Wire Brushes are flat steel strips mounted in wooden blocks.

Ideal for:

• Removing deposits of grease, wax, ink or food products
• Breaking up rubber-backed carpeting

Silabide Pad

Silibide Pads are ideal for scrubbing.

• Concrete
• Stone
• Metal
• Brick
• Wood

EDCO scarifiers come in manual push and self-propelled models. The working widths of these scarifiers range from 4″ on the CPM-4 to 12″ on the CPU-12.

Scarifiers can do a variety of surface preparation jobs including cleaning warehouse floors, texturing surfaces for adhesion of coatings, leveling sidewalks and uneven joints, grooving parking decks and removing traffic lines, paint and coatings.

Every EDCO scarifier is made with five basic components:

1. Four or six shaft drum loaded with steel or carbide cutters rotating either up-cut or down-cut at a high speed to remove surface materials
2. Power source (gasoline, electric, air, propane) to move the drum
3. ble depth control for adjusting the depth of the cut
4. Heavy-duty 7 gauge steel frame
5. EDCO’s unique engage/disengage that raises or lowers the cutting drum without losing the depth setting

Cutting

1. Open throttle, let the engine reach full speed
2. Lower “disengage lever” slowly. With “disengage lever” in full down position, cutter wheels should not be in contact with slab. Turn “depth adjustment crank” down until cutter wheels contact and begin to penetrate the slab. Continue turning slowly until desired depth of cut is reached. Depth of cut is predetermined by the job specifications.

Production rates are determined by material to be removed, hardness of slab and type of cutter being used.

To achieve a greater depth, it may be necessary to make several passes over the same area. Cutter wheels will jam if you try to remove too much material in one pass. Wheels will raise from the surface and the front will ride on the drum flanges. This will cause severe damage to equipment and cause cutters to flatten or break. Remove less material with more passes will save you time and money in the long run.

To keep your scarifier running at maximum efficiency, make sure to keep the drum balanced so the opposite shafts are set up identically. An unbalanced drum will cause excessive wear on bearings, frame and shaft. If there is excessive vibration or if you have doubts about how hard you are pushing the scarifier, stop working and inspect the shaft and cutters for undue wear.

Here are four ways to modify scarifying results:

1. Control the forward speed of the scarifier
2. Vary the speed the drum is turning
3. Vary the spacing and the type of the cutters
4. Adjust the depth you are cutting at

To Stop Cutting:

1. Raise the disengage lever
2. Reset the throttle to idle
3. Turn the ignition switch off