Pfaff 545 bobbin case opener jams the catch hook

[John D]

The following diagram is for a Pfaff 1245 but I'm using it to illustrate my issue with a Pfaff 545. When rotating the wheel movement stops as the part labeled #1 in the diagram jams with part #3. This freezes the movement of the bobbin carriage and the loop catch hook stops moving. When comparing to on-line videos I "think" parts #1 and # should just barely slide beside each other to let the movement continue. I have a post machine and part #1 actually lifts above part #3 to let the loop catch hook continue on its way. 

For the life of me I cannot figure out what needs to be adjusted. Is it a timing issue and I need to slip the gears in the gear box? do I need to adjust the bobbin bed?

Normally I would take this to the shop and fork over the big bucks. But I'm in the middle of sewing canvas and with a deadline . . . 

The Pfaff is brand new to me and is better suited for the work I'm doing as the flat bed is better than the post bed on my other machine. 

Anyhoo - any thoughts on what's going on? I would prefer to not wait a week if it can be helped. 

Thanks!

John 
I'

[LindanHotAir]

The purpose of part 1 is to rotate the bobbin case to open a space for the thread to pass between locating tab 4 and the notch under the needle plate.

[Constabulary]

Please post pictures and a video of your own machine so we can evaluate the issue better.

Are you sure #4 is in the notch of the needle plate as shown in the encircled picture? For adjusting the bobbin case opener loosen #2 adjust #1 the way thread keeps not hanging between #1 and #3 and in the gap between #4 and the needle plate (encircled picture) and tighten #2 again. But that should be mentioned in the manual I think.

[John D]

Video attached. The “clacking” sound you hear is when the two pieces touch. As far as I can tell the noise os from their striking each other. And the entire movement stops cold. If I engage the safety clutch I can move the needle up and down, but the bobbin case stops in the same place.

 

[Constabulary]

You have no needle plate installed - never run your machine without needle plate.

Install needle plate and make sure the small tab #4 sits in the gap in the needle plate as show in the encircled picture.

Edited July 24, 2021 by Constabulary

[John D]

1 hour ago, Constabulary said:

You have no needle plate installed - never run your machine without needle plate.

Install needle plate and make sure the small tab #4 sits in the gap in the needle plate as show in the encircled picture.

Thank and yes, never run without the needle plate. I took it off as the action is EXACTLY the same whether in place or not. Here is an image of the tab #4 lining up in the gap in the needle plate. 

I will post a video in a few minute of the same action with the needle plate in place. 

[DanishMan]

I guess you have to adjust the bobbin case opener.

[John D]

8 hours ago, DanishMan said:

I guess you have to adjust the bobbin case opener.

This was my thinking too. Thought how? I can't seem to find a manual or video, even looking for Pfaff 145 and the Juki 67 (I think it is). 

I'm usually able to internet search my way to learning and am totally stumped. 

Thanks in advance!

[LindanHotAir]

The bobbin case opener adjustment is performed by loosening the screw holding the opener. Adjust it so it moves the tab away from the edge of the notch in the needle plate as the thread goes between the tab and the notch. If it is properly adjusted the thread will not hang up or shred.

[DanishMan]

The 145/545 only has one screw to adjust the bobbin case opener. The 1245 has two, but the principle is the same. This is from the 245/1245 service manual.

Edited July 26, 2021 by DanishMan