Tension,

[Frodo]

My enemy my friend tension

how to achieve a happy middle ground. just when I thought I had this cat by the tail up pops tension issues

my understanding of. Tension is pretty straight forward, both threads should be equal . Only problem with that is my idea of equal and my machines idea of equal are not the same

asking for tips, tricks, and knowledge

[kgg]

30 minutes ago, Frodo said:

My enemy my friend tension

I think the bottom tension is to light. A couple of questions:

i) what machine are you using?

ii) are you doing a drop test on the bobbin to set the bobbin tension? Bobbin Drop Test: With the bobbin in the bobbin case and the end threaded through the tension spring and rested in the palm of left your hand grab the end of the bobbin thread with your right  You should be able to raise the bobbin case off your hand about an inch without unwinding. Giving the thread a quick jerk the thread should unwind slightly. A good little video: (https://www.youtube.com/watch?v=lVQWKXZVzu0

iii) are you sewing in pre punched holes?

iv) is the machine threaded properly? A couple of photo's of how you have the machine threaded from the thread spool to the needle may help.

kgg

 

 

[Beanwood]

Assuming this is still the Rex from the other topic - and that's the top thread that's loose? So tighten the top thread tension just a bit should help? 

[DonInReno]

Whenever tension adjustments seem harder than they should be it’s not a bad idea to double check the thread path for issues.

Watch out for thread that develops occasional kinks between the spool and machine, or even thread that sticks to itself and comes off the spool jerky (old bonded thread does this).

Badly worn thread guides with deep grooves can create extra tension when thread is down in the groove and alternating light tension when it’s not.

Then there are often grooves in the tension disks that might contribute to problems - tension disks are cheap to replace, but you can often sand and polish out light grooves.  Likewise, there may be deep grooves in the bobbin case, or a squirly spring.

Tension disk springs that are too light require a lot of turns to adjust and if they bottom out just need to be replaced.

The biggest gotcha that will drive a person crazy until it’s discovered is a tension release that won’t allow tension disks to fully close, making it strangely difficult to get knots to center -  it should be fairly straightforward to add a few cranks on the tensioner and have the knots move where you want them to be.  It’s common for replacement tension disks to have slightly different shapes/thicknesses so it’s a common issue to check.  On 111w155 type of machines it’s about the size of a 15g nail and is filed down or replaced with a longer one if the release isn’t opening the tension disks when presser foot is raised - have no idea what your machine uses, but the tension release will have some means of adjustment.  Ideally, lifting the presser foot part way, like when changing directions in a sharp corner or reversing, won’t release thread tension, but fully raising the foot does.

Having said all that, often the first thing I’ll do because it’s the easiest is go up a needle size and see if that clears things up.  The knot has to have room to be pulled up in the leather.  All the other issues in the thread path may still need to be fixed, but it lets you know that the hole isn’t the problem.

You're going to run out of things to adjust on this machine and have to pick up another fixer upper!

 

 

[Frodo]

2 minutes ago, DonInReno said:

 

You're going to run out of things to adjust on this machine and have to pick up another fixer upper!

 

 

 

I have an itchy palm it may be the first signs of singeritis

[DonInReno]

Lol 

I forgot to say to check the bobbin thread isn’t being pinched in the bobbin case opener, or in a groove in the bottom of the feed dog.  I bought one old factory machine that had a ridiculously deep groove in the bottom of the feed dog for some reason - like it was sewing something that required extra bobbin tension - that drove me nuts because I couldn’t see the groove, but something was obviously snagging thread as it was pulled up.

[CowboyBob]

22 minutes ago, DonInReno said:

 On 111w155 type of machines it’s about the size of a 15g nail and is filed down or replaced with a longer one if the release isn’t opening the tension disks when presser foot is raised - have no idea what your machine uses, but the tension release will have some means of adjustment.

The bracket behind the tension can be bent either way(by using 2-screwdrivers) to fine tune the opening of the discs & always needs to be done when installing a new one.You could ecchange the new bracket on the back & use the old one to save some time.

[Quade]

Quote

The biggest gotcha that will drive a person crazy until it’s discovered is a tension release that won’t allow tension disks to fully close, making it strangely difficult to get knots to center 

Haha. Happened to me.  I was touching the knee lift slightly but it was enough to release the tension. So it sewed properly most of the time but occasionally I'd get a nest of thread. 

[AlZilla]

13 hours ago, Frodo said:

My enemy my friend tension

how to achieve a happy middle ground. just when I thought I had this cat by the tail up pops tension issues

my understanding of. Tension is pretty straight forward, both threads should be equal . Only problem with that is my idea of equal and my machines idea of equal are not the same

asking for tips, tricks, and knowledge

 

69651400628__DC6CBB51-4C4C-463C-AEA2-992236EECA79.MOV 2.16 MB · 3 downloads

I don't know how you're setting your initial bobbin tension, but ...

I've been rehabbing mostly neglected domestic machines for a while.  Often the bobbin area needs a lot of attention. Crud, lint, corrosion, etc.  Rather than guess at bobbin tensions, I bought this crude little scale. At least it gets me in the ballpark on bottom tension. Then a good disassembly, cleaning and polishing of tension unit and thread guides and tensions haven't given me much trouble.

https://www.amazon.com/dp/B000HKPN7I?psc=1&ref=ppx_yo2ov_dt_b_product_details

[Frodo]

So which is it

top stitch line is controlled by the bobbin tension

and bottom stitch line is the top tension disc

 

or the other way around?

Of you have a nice tite top stitch line

but the  bottom is loopy,  adjust top tension?

 

[AlZilla]

Disclaimer: I'm a total novice with sewing machines and my comments are worth exactly what you paid for them.

I haven't had one get "loopy" due to tension.  But if the top thread is showing on the bottom, you could have too little top tension or too much bottom tension.  And vice versa. It's all about balance.  I have had a case where I couldn't quite get the top thread to stop peeking through when sewing a single layer - but sewing 2 layers, it disappeared into the fabric.

I have a nearly brand new Brother domestic that was getting loopy on the bottom (with top thread). Turned out that on that modern machine, since the tension arm is mostly enclosed in the case, I wasn't quite getting the thread well into the end of the arm. It would loose the thread from the end of the tension arm (which I couldn't readily see) and caused no end of trouble.

For me, anything the thread touches (top or bottom) has to be clean and maybe even polished. If you're seeing big loops, it seems like more than a simple tension issue.

I'm following this one to learn and admire your determination.

[DonInReno]

This chart is only accurate if the needle is large enough to allow the knot to be pulled up in the material.   
 

For 95% of all sewing the bobbin tension isn’t messed with other than the initial setting.   With the bobbin in the bobbin case and holding just the thread, gravity shouldn’t let the bobbin/case fall.   If the thread is then giggled up and down gently the bobbin should start to pay out thread.