Archer 884 - The machine tangle the threads from the bottom, sews loosely

Hello,

I bought a second-hand Łucznik 884 sewing machine.
The machine is operational, but requires repair or adjustment.
The machine sews, but tangle the threads from the bottom, at best the bottom seam is loose.
I read threads about adjusting this machine and followed all the instructions, but the problem remained unresolved.
I am enclosing a few photos presenting the problem.
As you can see in the photos, the underside of the threads is tangled or the seam is loose, while the seam looks normal from the top.
I adjusted the tension of the upper thread, but it didn't change anything.
I took out the bobbin case, it turned out to be chipped, as shown in the last photo. However, I don't know if this can be the cause of these problems or if it has an impact on sewing quality.
If this can be the cause of these problems, I will get a new drum, but I'm afraid it won't get the job done.

Thank you in advance for your response.

Loosen the bobbin thread tension in two to three steps and adjust the stitch width to 3. Loosen the presser foot slightly. it should be OK . As for the eardrum. It must be intact and undamaged


That's what my wife says, but I don't know if she is right because I don't know anything about it

Such damage to the bobbin may cause the thread to catch on a dent while sewing, and the stitch will be wrong or the thread will break,
You must first a new bobbin and then adjust the stitch.

Thank you for your answers, I will equip myself with a new drum and we will see if it is enough. I wonder how to loosen the thread in the bobbin case. I know how to loosen the upper thread, but I do not know how to adjust the bobbin thread tension.

Looking at the screws on the side of the bobbin case, adjust with the left screw.
Tension should be minimal.

For me, the situation is identical.
The trouble started when I was forced to gently shift the toothed wheel driving the material feed. The pulley is half worn (teeth worn). After a slight shift, the wheel engages - the feed works, but the situation is the same as for the author of 1 post in the topic. Anyone suggest something? THX in advance

Since the teeth of the toothed rack driving the feed tooth transport were damaged, the needle settings in relation to the transport could also shift. Both gears must be replaced or the correct operation of the needle in relation to the transport teeth must be checked and adjusted. The forum has already described in detail how to do this, just search.

Thanks for the suggestions, so I will look for a way to regulate

Maybe something will help:

Hello, did you get along with these machines? I have the same situation, tangling a thread underneath. The replaced gears, bobbin case and preset tensioner adjustment do not give anything, take the thread from the bobbin. Can anyone help?

Welcome

I had a problem with sewing, and more precisely with the thread tensioner. I have described it here
https://www.elektroda.pl/rtvforum/topic3035389.html

greetings

Tensioner or looper?

In my case, this happened after replacing the bemben with a new one. The new one had less rounded edges and was probably a tad higher. I went back to the old one and it works.