Exchanging The Sewing Hook In The Pfaff 360; The Position Finger Brocket - Pfaff 260 Service Manual

Exchanging the Sewing Hook in the Pfaff 360
If
it should become necessary to replace a
dama~ed
sewing hook, hold the
balance wheel, pass a screwdriver through the aperture at the back of the
cylinder arm, and take out screw a (Fig. 85). Turn the screwdriver clockwise
because this screw has left-hand thread. Next, remove the position finger
bracket, and cautiously pull the hook with the hook shaft out of the machine.
Make sure though that you remember the position of the sewing hook in the
machine.
Fig. 85 Dismantl ing the Pfaff 360 sewing
hook and its shaft
o = Set screw
b
=
Hook shaft bush ing
c
=
Hook shaft helical gear
. d
=
Spacing washer
e = Hook 'thrl!!od gunrd
f
=
Sewing hook
g
=
Gu ide bushing
When inserting the new hook, take care that the clearance between the hook
point and the needle does not exceed .004", or 0.1 mm. If adjustment is re-
quired, add or remove an appropriate number of spacing washers until the
correct clearance has been obtained. Replace the hook in exactly the same
position which was occupied by the damaged hook before. Insert and tighten
the hook set screw, turning it counter-clockwise. Replace and screw down the
position finger bracket. To set the needle bar rise, follow the procedure out-
lined on page 49.
The Position Finger Bracket
After adjusting the clearance between hook point and needle on Pfaff machines
260 and 360, it is absolutely necessary to recheck the position of the posi-
tion finger bracket. Unhindered passage of the needle thread loop through the
clearance gap greatly depends on the position of the bobbin case position
finger in the position slot of the bobbin case base. This finger
is
positioned
correctly if there is a clearance of about
1
/n", or 0.7 mm, between its tip and
the bottom of the position slot (Fig. 86).
Important
If the position finger does not project into the slot far e nough, the bobbin case
will not be held in place securely. And, conversely, if the position finger bears
against the bottom of the slot, the needle thread will jam and break. To adjust
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