Walking foot knocking on feed dogs

[Marievee]

Hi everyone hope someone can help. I have a jack H2 walking foot machine. It is very similar to a juki 1181. It has just recently started making a knocking noise. This is caused by the outer presser foot banging onto the feed dogs. I’ve not changed anything on the machine only adjusted the pressure nuts on the top of the machine. Shall I lower the feed dogs slightly or try to lift the outer presser foot?

jack instruction manuals are worse than useless. 
thank you 

[Matt S]

Hi @Marievee, how and why is the outer foot hitting the feed dogs? Unless you're running it empty without the foot raised (don't do that) there should be leather in between the two. Are you absolutely certain there isn't some other cause -- that the outer foot isn't hitting the inner foot for instance?

Sewing machines, like all mechanical devices, tend to move, slip, wear and adjust themselves over time. This happens more often with "not exactly top quality" machines such as Jack. Although you may not have conciously  made the change, something has changed. We just have to figure out what and how to put it back how it was. Even a thread jam or needle strike can knock the machine out of time.

I've found through hard experience not to start adjusting things willy nilly when something goes wrong. That's a quick way to turn a simple problem into a complex one! To paraphrase one of my machine's manuals "do not adjust any part of this machine unless you know exactly what it does, why you're adjusting it, and how its adjustment will affect the other parts of the machine".

I understand your frustration with the instruction manual, but it's about as verbose as any industrial sewing machine manual gets. They don't go into all the detail like you'd get with a domestic machine or other consumer good because they expect the user to be a factory worker (where an experienced operator would train them how to use the machine) or an experienced lone worker/craftsperson. My carpentry tools didn't come with instructions how to be a carpenter either!  Luckily we live in an age where websites such as Leathwerworker.net and Youtube allow generous and experienced people to provide enormous amounts of valuable information for free so it's never been easier to learn these skills.

Would you be able to shoot a short video (with sound) of the machine exhibiting the problem? That would be the quickest and easiest way to diagnose the problem over the internet.

[kgg]

8 hours ago, Marievee said:

This is caused by the outer presser foot banging onto the feed dogs.

My first guess is the feed dog is to high and banging the pressor foot. I would first download the Juki Du1181n manual and compare the height of your feed dog to that of the Juki 118. If it is out of spec it is a simple adjustment outlined on page 27.

kgg

[chrisash]

Check the inner foot has not rotated a bit and hitting the outer foot

[Marievee]

Thanks for your replies. I think the inner presser foot is the problem. It doesn’t feel secure it rotates slightly and it looks too high when the needle is in its lowest position. How do I adjust to make it secure? I know it would be better to get someone out to sort it but it’s easier said than done with current restrictions. 
thank you everyone 

[kgg]

I would first check https://www.manualslib.com/manual/1155862/Juki-Du-1181.html?page=6#manual    of the Juki Du1181n Engineers manual.

kgg

[Marievee]

I’ve looked it doesn’t tell you how to tighten the inner presser foot. 
thanks though

[DrmCa]

1. Post photos.

2. What is your source of feet?