Brother T-8421C Instruction Manual page 31

<A>
<B>
<C>
<Bobbin case type>
1. Insert the bobbin (1) into the bobbin case (2) so that the
winding direction is as shown in the illustration.
2. There are three types of cap (2) (<A>, <B> and <C>).
Thread the thread by one of the following methods in
accordance with the shape of the bobbin case (2) being
used.
<A>
1)
2)
2902M
<B> <C>
1)
2)
3)
3. Insert the bobbin case (2) into the rotary hook.
4. Push latch (9) of the rotary hook flat.
5. Close the slide plates.
3126M
3127M
2467B
There is an anti-spin spring (10) inside the rotary hook. The
anti-spin spring (10) prevents the bobbin from racing at
times such as during thread trimming.
Use bobbins (1) made of light alloy as specified by
BROTHER.
2468B
T-8421C, 8422C, 8452C, 8722C, 8752C
4. PREPARATION BEFORE SEWING
Pass the thread through slot (3) and under the
thread tension spring (4).
Pass the thread through the thread hole (8) and pull
out about 50 mm.
Pass the thread through slot (3) and under the
thread tension spring (4).
Pass the thread through slots (5) and (6), and then
through the spring (7).
Pass the thread through the thread hole (8) and pull
out about 50 mm.
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