We just got a pfaff 138 and put T-90 industrial thread but it keep breaking the thread. i cant figure out why, it seems to be threaded correctly. any thoughts?

put the bobbin in the bobbin carrier correctly so that the thread unwinds in the right direction

This may be helpful:

Understanding Thread Tension Threads

Sewing Machine Problem 1 Thread Breakage

Sewing Machine Thread Keeps Breaking

Consult your owner's manual. First thing to do is verify that it is threaded correctly. This is probably the #1 cause for breaking thread. #2 is most likely the tension being too tight. #3 sometimes is the incorrect needle or installed incorrectly.

Check the suggestions here:
The thread keeps breaking Sewing Machines

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here are 2 links, choose which one you want to buy from
Pfaff 138 138 6 Instruction Manual
Pfaff 138 Parts

Go to this webpage to download one, it is free but you must register.
http://www.sewingmachinemanuals.com/pfaff-138

The top thread breaks

1. the needle thread is not threaded properly

2. The needle thread tension is to tight

3. The needle is bent or blunt

4. The needle is incorrectly inserted

5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew

6. the threads were not drawn to the rear after sewing

7. The thread is either to heavy or to fine for the needle

8. Try a different spool or cone of thread

The top thread breaks

1. the needle thread is not threaded properly

2. The needle thread tension is to tight

3. The needle is bent or blunt

4. The needle is incorrectly inserted

5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew

6. the threads were not drawn to the rear after sewing

7. The thread is either to heavy or to fine for the needle

8. Try a different spool or cone of thread

The top thread breaks

1. the needle thread is not threaded properly

2. The needle thread tension is to tight

3. The needle is bent or blunt

4. The needle is incorrectly inserted

5. The needle thread & the bobbin thread are not set under the presser foot when starting to sew

6. the threads were not drawn to the rear after sewing

7. The thread is either to heavy or to fine for the needle

8. Try a different spool or cone of thread

Bobbin thread breaks


1. There is a right way & wrong way to insert the bobbin in the case --when you insert the bobbin in if it doesn't stitch correctly turn the bobbin over see if that helps or bobbin case is not inserted correctly


2. Lint has collected in the bobbin holder


3. The bobbin is damaged & doesn't turn smoothly


4. Lower thread tension is two tight

This happened to me. Shucks, I had the wrong needle in; it was too short to reach the bobbin thread and pick it up. Installed correct needle (repair man did) and viola. . .

First make sure your needle is in correctly. Then make sure you are threading the machine correctly especially make sure you thread the take-up lever. Make sure your tension dial is at a 4 to 5. if this does not work, let me know