DT3-B291
78
12. TROUBLESHOOTING
12. FEHLERSUCHE
12. RESOLUTION DES PROBLEMES
12. LOCALIZACION DE AVERIAS
Problem
Possible cause
Page
5. Uneven stitch length
• Is the presser foot pressure too weak?
Adjust the presser foot pressure.
• Are the heights of the feed dog too low?
Adjust the heights of the feed dog.
6. The hole made by the
needle is too wide.
• Is the needle blunt?
Replace with a new needle.
• Is the needle too thick for the material?
Replace the needle with a needle that is one rank thinner.
7. The chaining-off stitch
is not formed prop-
erly.
• Is the thread tension too strong or too weak?
Adjust the thread tension.
• Is the needle bent or broken?
Replace the needle if it is bent or broken.
• Are the needle and looper installed in the correct positions?
Adjust the height of the needle bar and the position of the looper.
• Are the positions of each of the thread paths correct?
Check the positions of each thread path.
• Is the position of the needle guard correct?
Adjust the position of the needle guard.
• Is the tip of the looper broken?
If the looper is damaged, smooth it with an oiled grindstone or replace
it.
• Is the presser foot rattling?
Increase the presser foot pressure.
• Are the heights of the feed dog appropriate?
Adjust the heights of the feed dog.
• Are the chaining-off stitches being cut by the feed dog?
Decrease the presser foot pressure.
8. The material is greatly
puckered around the
seam.
• Is the needle too thick?
Select a needle which is suitable for the material and the thread.
• Is the presser foot pressure too strong or too weak?
Adjust the presser foot pressure to an appropriate pressure.
• Is the thread tension too strong?
Adjust the thread tension.
• Are the heights of the feed dog appropriate?
Adjust the heights of the feed dog.
• Is the needle feed amount in the correct proportion to the lower feed
amount?
Adjust the ratio between the needle feed amount and the lower feed
amount.
33
65
32 – 33
21
48, 52, 57
44 – 47
59
52 – 53, 57
33
65
33
20
33
32 – 33
65
49
21
21
0473M
0474M
0475M