Bosch Power Tools 25618-02 Operating Tips, Driving With Variable Speed, Fastening With Screws

Models: 25618-02 25618BL 25618-01

1 52
Download 52 pages 9.24 Kb
Page 15
Image 15
Operating Tips

BM 2610027761 08-12_BM 2610027761 08-12.qxp 8/17/12 1:54 PM Page 15

Operating Tips

You will extend the life of your bits and do neater work if you always put the bit in contact with the work before pulling the trigger. During the oper ation, hold the tool firmly and exert light, steady pressure. Too much pressure at low speed will stall the tool. Too little pressure will keep the bit from cutting and cause excess friction by sliding over the surface. This can be damaging to both tool and bit.

DRIVING WITH VARIABLE SPEED

The technique is to start slowly, increasing the speed as the screw runs down. Set the screw snug yl by slowing to a stop. Prior to driving screws, pilot and clearance holes should be drilled.

Always hold the machine straight on the bolt to be tightened.

The best method to determine the right impacting/tightening duration is by means of a trial. For small screws, the right impacting/tightening duration can be reached in less then 0.5 Sec. Therefore, work with low RPM and switch the machine off immediately when the screw is tight and the impacting sound can be heard.

For screwing larger, longer wood screws into hard material, pre-drilling is the best method.

TIGHTENING TORqUE

(Models 24618 & IWH181 only)

The tightening torque depends on the duration of the impacting/tightening action. The largest tightening torque is achieved after approx. 6 to

10 Sec. impacting/tightening action.

The torque build-up depends on the following factors:

Hardness of the bolts/nuts.

Type of washer (disk washer, spring washer, seal).

Hardness of the material to be joined.

Lubricating effect at the surfaces of the junction.

This leads to the following application cases:

Hard case: The joining of metal to metal with a disk washer. The maximum torque is reached after a relative short impacting/tightening action.

Medium case: The joining of metal to metal where spring ring washer, disk spring washer, stud bolts or bolts/nuts with conical seats are used.

Soft case: The joining of e.g. metal to wood or insulation material.

For middle or soft joining cases, the maximum tightening torque is less as for hard cases. Therefore, a longer impacting/tightening action is necessary to arrive at the maximum tightening torque.

FASTENING WITH SCREWS

This procedure shown in (Fig. 9) will enable you to fasten ma erialst together with your tool without stripping, splitting or separating the material.

First, clamp the pieces together and drill the first hole 2/3 the diam eter of the screw. If the material is soft, drill only 2/3 the proper length. If it is hard, drill the entire length.

Second, unclamp the pieces and drill the second hole the same diameter as the screw shank in the first or top piece of wood.

Third, if flat head screw is used, countersink the hole to make the screw flush with the surface. Then, simply apply even pressure when driving the screw. The screw shank clearance hole in the first piece allows the

FASTENING WITH SCREWS

1.  Drill 2/3 diameter and 2/3 of screw length for soft materials, full length for hard materials.

Apply a slight even pressure when driving screws.

DRIVING WITH VARIABLE SPEED 2.  Drill same diameter as screw shank.

TIGHTENING TORqUE 3.  Countersink same diameter as screw head.

Screw

screw head to pull the pieces tightly together.

FIG. 9

-15-

Page 15
Image 15
Bosch Power Tools 25618-02 manual Operating Tips, Driving With Variable Speed, TIGHTENING TORqUE Models 24618 & IWH181 only