Bosch Power Tools 1853-5 Operating Instructions, Sanding Operations, TRI-CONTROL Paddle Switch

BM 1609929H55 1-05 1/5/05 3:17 AM Page 10

Operating Instructions

"TRI-CONTROL" PADDLE SWITCH

The “Tri-Control” Paddle Switch enables the operator to control the switch functions of "Lock-OFF", "ON/OFF" and "Lock-ON".

TO UNLOCK SWITCH AND TURN TOOL "ON": Push paddle lever FORWARD (toward the spindle) then squeeze the paddle lever.

TO SWITCH TOOL "OFF": Release pressure on paddle lever. The switch is spring loaded and will return to "OFF" position automatically.

The "Lock-ON" feature, incorporated into the paddle switch, is a convenience for long operations.

TO LOCK SWITCH "ON": After paddle switch has been activated push paddle lever completely FORWARD and release paddle lever.

TO SWITCH TOOL "OFF": Squeeze and then release paddle lever. The switch is spring loaded and will return to "OFF" position automatically.

!WARNING Hold the tool with both hands while starting the tool,

since torque from the motor can cause the tool to twist.

Start the tool before applying to work and let the tool come to full speed before contacting the workpiece. Lift the tool from the work before releasing the switch. DO NOT turn the switch “ON” and “OFF” while the tool is under load; this will greatly decrease the switch life.

Sanding Operations

SELECTING SANDING DISC

Sanding discs are made of extremely hard and sharp aluminum oxide grits, phenol-resin bonded to a sturdy fiber backing for fast heavy-duty service and long life. The discs vary as to size and spacing of the abrasive grits. OPEN COAT (type H) — used for soft materials and on paint or varnish. CLOSED COAT (type K) —used for metal, hardwood, stone, marble and other materials.

Sanding discs range in grit from 16 (very coarse) to 180 (very fine). To obtain best results, select sanding discs carefully. Many jobs require the use of several grit sizes and

at times both “open coat and closed coat” discs are required to get the job done faster. See chart for application examples.

Operation: Refinishing painted wood or metal surfaces.

REMARKS	GRIT
To remove paint and to smooth	Coarse
surface irregularities.	16-24-30
To smooth	Medium
the rough sanding.	36-50-80
To remove scratches left by	Fine
previous discs.	100-120
To smooth surfaces for painting,	Very Fine
polishing or waxing.	150-180

SANDING TIPS

For best results, tilt the Disc Sander at a 10° to 15° angle while sanding so that only about 1" of the surface around the edge of the disc contacts the work.

If the disc (accessory) is held flat or the back edge of the disc comes in contact with the work, a violent thrust to the side may result.

If sander is tilted too much, sanding action will be too great and a rough cut surface or gouging and snagging will result.

Guide the Disc Sander with crosswise strokes. Be careful not to hold the sander in

one spot too long. Do not use a circular motion, as this makes swirl marks. Test before use on scrap stock.

Do not force or apply pressure when sanding. Use only the weight of the tool for pressure. Excess pressure actually slows the tool down. If faster stock removal is desired, change to a coarser grit disc.

Remove gummy paint from metal with an “open coat” disc. Sand until sparks start to appear, then stop and change to a “closed coat” disc to remove any remaining paint.

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