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Dowel fastening:
The most common way of fastening is
dowel fixing
.
If possible, use metal dowels only. The dowel diameter must not be
smaller than 12 mm.
In order to fasten the drilling unit correctly, you need the fastening set
(order number 35721).
Drill a hole with a diameter of 15 mm, 50 mm deep. Make sure that
the hole is free of dust.
Insert a dowel and open it with an expanding mandrel.
Screw the thread rod into the dowel.
Put the drilling unit with the deep hole in the base onto the thread rod.
Place the washer and screw the butterfly nut very tightly.
Adjust the drilling unit in the platform by using the four screws.
Drilling
Vertical drilling
Switch the PRCD on.
Open the water supply.
Switch the motor on without touching the surface with the drill bit.
Turn the handle to bring down the drill bit until it contacts the surface.
In order to reach an exact centring of the drill bit, keep the feed low
for the first centimeter of cutting depth.
Then you can drill faster. A too small drilling speed reduces the
power. On the other hand, when the drilling speed is too high, the
diamond segments quickly become blunt.
Angular drilling
Remove the screw in the foot base which arrests the column at 90°.
Loosen the two screws on the base of the column and turn the
column to the requested angle.
Retighten the screws again.
At the beginning, it is better to drill very slowy because the bit only
meshes with a fraction of its cutting area with the material. If you drill
too fast or with a pressure which is too high, the bit can be off centre.
You have hit reinforced iron when you recognise while drilling that the feed
rate gets very low, when you need to use more force, or when the water
leaking from the bore hole clearly shows some metal chips.
Reduce the pressure on the drill bit to cut through the reinforced iron
without any problems. You increase the pressure again when you have cut
through the reinforced iron.