Delta 17-935 Manual Del Usuario página 6

SPINDLE SPEEDS
The correct spindle speed depends on the size of the bit and the hardness of the wood. Your best cuts are generally
in the range of 650 to 1800 RPM. Use a slower speed for larger bits and harder woods and faster speeds for smaller
bits and softer woods.
MORTISING CHISEL AND BIT COMBINATIONS
OPERATION
Place the workpiece on the table and adjust the height of the table so that
the point of the chisel clears the work about 1/2". Lower the chisel along
the side of the workpiece to gauge the depth of the mortise. Adjust the
depth stop of the drill press to control the depth of the mortise. Adjust the
guides (X) Fig 21 to hold the work against the fence (Y), tilting them if nec-
essary. Lower the hold-down (Z) against the top of the work. This hold-
down should hold the work in place, but should also allow the workpiece
to slide to its next position. These hold-down arms are independently
adjustable. Once you have them adjusted, tighten the thumb screws (T).
Loosen the locking levers (S) Fig. 21 that hold the mortising attachment
fence to the drill press table. Shift the fence forward or toward the column
to being the workpiece to the desired position under the mortising chisel.
Tighten the locking levers.
Slide the workpiece along the fence to ensure that the cuts will be aligned. Loosen the lock handle (Y) Fig. 21 and turn
the chisel in the holder (if necessary) to make its faces square with the cut. Tighten the lock handle (Y).
NOTE: If the fence and face of the chisel are not parallel, the cuts will be staggered.
NOTE: Make mortise cuts to the far left and far right first, then make the cuts in between. This method allows all four
sides of the chisel to make a true vertical cut on each end.
NOTE: Do not attempt to mortise deeper than maximum depth listed for each chisel as indicated in Fig. 22. Going
past these limits will clog the ejection slots and you will damage the tool or the bit.
NOTE: Practice on scrap material before you use an actual workpiece.
NOTE: For through mortises, place a piece of 1/2" plywood between the workpiece and the drill press table to
eliminate splintering.
SHARPENING CHISELS AND MORTISING BITS
Sharpening these chisels requires considerable skill and practice. An improperly-sharpened hollow chisel can easily
split in operation, and an old bit will cause excessive strain on the hollow chisel, causing breakage. Therefore, we
recommend that you find an expert rather than doing the job yourself.
MORTISING CHISELS
WITH 5/8" X 1-1/2" SHANK
Depth Capacity
Size
1/4" x 1/4"
5/16" x 5/16"
3/8" x 3/8"
1/2" x 1/2"
6
Fig. 20
T S
Z
X
1-7/8"
1-7/8"
3"
3"
Fig. 22
Y
T
T
S
Fig. 21