Singer 18-2: can't get the tension right

[Nico619]

Hello everyone, I bought a few months back a 100 year-old Singer 18-2, in very good conditions, and i've been using it since then. The machine stitches very well, but I still have a problem with getting the upper and lower tensions right.
In particular, every time i use it, the upper thread seems too loose at the bottom.

I'll add as many pics as i can to show the problem and the conditions of the machine.

As soon as i got it i replaced the spring in front of the tension disk (the one that goes up and down with the thread) with a new one.

Since the top thread is visible at the bottom, i tried to tighten the tension disk by a lot, on top of loosening the bottom tension on the shuttle. That didn't solve the problem at all though.

 

In the pictures the black thread is the top one, whereas the brown one is the bottom one.
You will also see that the tension isn't that tight in the picture, but i also tried, as stated above, with a much much tighter setting, while still not getting the problem solved.

I'm starting to think that the reason might be something else, but i don't know what.

Thanks in advance for reading through it.

 

[Tigweldor]

Here is the manual for your machine.

Have another good look at your top thread routing - and needle height.

https://www.manualslib.com/manual/364456/Singer-18.html?page=2#manual

 

Greetings

Hans

[Nico619]

2 hours ago, Tigweldor said:

Here is the manual for your machine.

Have another good look at your top thread routing - and needle height.

https://www.manualslib.com/manual/364456/Singer-18.html?page=2#manual

 

Greetings

Hans

Thanks for the answer.
I checked the manual earlier today, and the top thread routing seems to be done just like in the manual (i posted a picture above, if you want you can check).
How would the needle height influence the tension thing?

Nicola

[Tigweldor]

if the needle goes down to deep, an overly large loop is formed by the time the hook can grab it.

This will then not form a proper stitch.

In the manual there is a little chapter on how to exactly set up needle height.

Greeting

Hans

[Nico619]

15 hours ago, Tigweldor said:

if the needle goes down to deep, an overly large loop is formed by the time the hook can grab it.

This will then not form a proper stitch.

In the manual there is a little chapter on how to exactly set up needle height.

Greeting

Hans

Alright, i've done some modifications, that is making the check spring tighter (i think it's bouncy enough now. Earlier it might have been looser) and changing the needle height. When the shuttle hook was passing next to the needle's dig, it'd be at the very bottom of it. Now, as you see in the video, it's right in the middle.

I also loosened a bit more the bottom tension and tightened the upper tension (check the pics). Despite all that, the top thread still shows up at the bottom.

In the picture the black thread is the top one. The light brown one is the bottom one.

I put the video and the pics on this imgur link: https://imgur.com/a/ArIpoUj

Any ideas what else could cause it?

[Tigweldor]

The way  I see it in the pics - your bottom thread is almost bigger size than your top thread.

I most always run my bottom thread one size smaller than top thread.

You should leave bobbin setting as it is and just try a smaller size, different bobbin thread.

Costs nigh to zero - some threads just don´t work the way you want them to, no matter how long you fiddle around.

As you get more experienced with your machine - you will be able to tell if bobbin settings are right just by pulling on the thread - it is a "feel" that can not be explained - you have to feel how much force is needed to extract more thread from the bobbin - sort of a muscle memory, if you know what I mean.

 

To see if the hook meets the exact middle of the scarf of the needle - mark the scarf smack dead center with the smallest black sharpie that you own.

When the hook is just on the outside of the needle - it should perfectly align with your black mark.

With all the bright shiny surface, it is hard to tell the way it is now.

Greetings
Hans

Edited 1 hour ago by Tigweldor

[Nico619]

41 minutes ago, Tigweldor said:

The way  I see it in the pics - your bottom thread is almost bigger size than your top thread.

I most always run my bottom thread one size smaller than top thread.

You should leave bobbin setting as it is and just try a smaller size bobbin thread.

Cost nigh to zero - some threads just don´t work the way you want them to, no matter how long you fiddle around.

 

To see if the hook meets the exact middle of the scarf of the needle - mark the scarf with the smallest black sharpie that you own smack dead center.

When the hook is just on the outside of the needle - it should hit your black mark.

Greetings
Hans

The two threads are actually identical. Same brand and same thickness, just different color. The dark brown i used earlier (for the bottom thread) was thinner, and in both cases the result is the same you see.

I tried the marker thing on the needle and now it's right in the middle.

I'm starting to think.. What i'm testing it on right now is a box calf leather (a bit more rigid, around 1.4 mm) on top, and a tumbled goat skin at the bottom (0.8 mm, for shoe lining). Is it possible that even if the tensioning was completely perfect, because of this leather it would still show the top thread a bit? Maybe the needle opens up the soft leather too much and no matter what it shows the top thread.. what do you think?
 

[Tigweldor]

Can not tell you - to be honest.

Have never sewn goat leather - nor such thin leather (0,8mm).

You´ll have to wait till someone more experienced on that comes along.

Do you have any other thread, so you can try a thinner size in the bobbin ?

Just as an experiment - if not, just flip the leathers and put the thick stuff on the bottom, the thin stuff on top.

 

Greetings

Hans