Delta ShopMaster MM300, Instruction Manual

Page: 14 / 18

14
SLIDING FIT BETWEEN
HEAD AND COLUMN
A dovetail gib (A) Fig. 32, is provided on the rear of the
head to insure a good sliding fit between the head and
the column when the head is raised and lowered.
Adjustment is made by loosening the two screws (B) and
turning adjusting screws (C). Then tighten two screws
(B).
NOTE: Correct adjustment is when a good snug
sliding fit is obtained without any side movement
between the gib and the column. This adjustment
should not be too tight that it restricts the sliding
movement or too loose that it affects accuracy.
Fig. 32
C
B
B
A
OPERATIONS
Fig. 33
B
A
Fig. 34
1. Make sure that chisels and bits are sharp.
2. Fig. 33, illustrates a typical mortising operation.
Note that the opening (A) in the chisel is to the right. This
means that after the first incision is cut, the workpiece
should be moved to the right for subsequent cuts. This
allows chips to escape freely through the opening in the
chisel.
3. Make sure the workpiece is held firmly against the
fence when cutting and that the holddown (B) Fig. 33, is
properly adjusted. The rate of penetration of the chisel
must be fast enough to prevent burning at the tip of the
bit, but not too fast as to stall the motor. You may en-
counter smoke from the bit or material once the chisel has
engaged the material. The smoke created is a natural
operating occurrence in hollow chisel mortising and is
caused by material chip friction and the resins in the
stock being burned off. Bluing of the chisel after initial
use is not indicative of a dull chisel, but a combination
of friction and resin buildup on the cutting faces of the
chisel. A dull chisel can be detected by the amount of
excess force required to complete a cut.
4. When performing a through mortise, a thin piece of
wood should be placed between the workpiece and the
table. This prevents “chip-out” at the bottom of the
mortise and also prevents damage to the table.
5. Fig. 34, illustrates the mortising operation
completed.