Thread Tension

[baileyuph]

I might think to much or is with to little thinking power?  I guess one sustains the other.

Any who, machine manuals instruct how to set a seam tension, you know the rest but the sewn seam, at the best tensions on the machine threads are when they tie in the middle.

Now, the thinking.  If this is when the tension is equal in the sewn seam, give it some thought about the machine upper and lower tension.  The correct setting doesn't indicate that the upper and bobbin threads are adjusted to the same tension, does it?

Why is one machine thread usually required to be tighter than the other?  What sets the stage for this anomaly and what varies this situation?

It has been said, "I seldom touch the tension setting on my machine".  I fully understand that especially if using the same and doing the same with the machine.  Same needle, same thread, etc.

I am not quite that routine, I suppose, for my sewing in furniture, auto, auto restoration, and marine does frequently require resetting on any one of my machines because thread size changes, etc. 

One correlation with this is, the thicker the materials being sewn, generally the tighter the upper thread tension required.  Why is this and if your experience isn't this, what other adjustments do you make (like a needle size change)?

Sometimes I have noted that the machine upper tension has to be much tighter than I would expect when doing certain seaming in things like plastic welt on older autos. 

Any experience or thoughts of enlightenment on tension?  I have not been led to believe that there is a significant difference in machines, provided they have been designed for the work or task involved.

Let me hear for further understanding,

Doyle

[sofadoc]

I wouldn't say that I never adjust the tension. But I would say that I seldom adjust the lower tension on the bobbin case. If it's too loose or too tight, I compensate by adjusting the top tension.

[Mojo]

It is pretty easy for me. I sew with either Solarfix 2000 or Sunguard 138. I use no other threads. I have one bobbin setup for Solarfix and one bobbin set up for Sunguard and then like Dennis I adjust the top tension accordingly.

It is a known fact on here that I suffer from OCD so I actually have scrap acrylic laying around and I mimic a topper by folding the acrylic, sewing a little then inspecting my knots with a magnifying glass. I strive for perfect knot placement which is in the middle.

I cannot tell you why - no idea if it is my machine, the material I sew or the thread I use but I rarely reset tension. The only time I do is when I am cleaning the machine and take the tension discs apart. Bob Kovar got me in the habit of cleaning the upper discs as well as blowing out the bobbin case.

I never have tension problems. When I go from Solarfix to 138 I know exactly how much to set the upper tension knob - 1 full twist.It also helps to have two bobbins ready to go and set for each different type thread.

Chris

[baileyuph]

I sew a larger variety of different weight and density (or types) of materials, in doing so, it keeps the upper tensions continuous changing and sometimes even the lower bobbin thread.  Especially if the thread weight changes.

Chris, you got it made with only two threads and having individual bobbins to cover those two requirements.

Do you change stitch length very much?  I do.  Auto is just that type of work.  Please understand, in restoration back to original, stitch length is one of the things owners want to be equal to original.  That is true down to seat belts.  Talk about tension changes, try seat belts, particularly duplicating OEM stitching.

Doyle

[MinUph]

I'm gonna hijack this thread and ask DB what thread they use on seat belts. I use to use NYMO but its not made any more.

Sorry.

[Mojo]

I rarely ever change stitch length Doyle.

I never considered stitch length on restoration work for autos. Very interesting and makes sense. :)

Chris

[baileyuph]

You are right about NYMO Paul, we use Polyester and try to match the weight.

For some of the popular cars, we get the sewing work on the belts and they are buying the reproduction labels, we position them to the old belt positions.  I know the owner of the business who makes the labels.  He researched the label content and has done a remarkable job in that specialty reproduction market.

These car restorers, the ones winning the national events, are really advanced.  I notified him about OEM GM buttons and hardware for seat upholstery at this time, he has resources and I expect him to come up with an equal to OEM.  Next I want to get him excited about the belt machine.  

Stitch length is paramount to everything also Paul.

Doyle

[baileyuph]

Didn't I read somewhere that while tying in the middle is the objective but not at the expense of sewing with tension that is too tight.

That makes sense because one can tie in the middle but done with different overall tensions.

Also, from reading, where don't remember but the point was made that there is a tendency to sew with tensions set too tight.

Mojo, you sew with two bobbins, one a larger thread; question, does the tension on both thread sizes seem equal?  You just pop in the bobbin you need and sew, no adjustment to top thread regardless of which size thread you are sewing.  There has to be a difference in your tension, larger thread would run tighter -- right?

Doyle

[Mojo]

Doyle I have two bobbins. I set one up for the correct tension for Solarfix. The second bobbin I set the tension for 138. I then use those two bobbins only for those two threads. I then set the top tension for Solarfix. if I sew 138 then I swap bobbins and pout the 138 bobbin in place and then back off the upper tension one turn.

When I go back to Solarfix I repeat but give the upper tension one turn in. So I am resetting the upper tension only. I am actually resetting the bottom tension but I do this just by swapping out bobbins with the tension already preset. It saves me time and I get consistent tightness on the thread.

Chris

[baileyuph]

Thanks Chris, now I understand how you handle the upper tension change.  Your situation is convenient in that there are two materials, two tensions. 

Doyle

[Mojo]

When I first started I used to use V90 and 138. Setting the tension on my old Tuffsew was a very frustrating experience. I ended up having to just use 138 because I lost so much time messing with tension adjustments every time I changed thread.

That Tuffsew would make the Pope cuss and swear. What a complete hunk of junk. :)

Chris

[baileyuph]

Chris,

You talked about the Tuff Sew machine you used and how you didn't like it.

Do you know what the big problem was with that machine?  Was it a walking foot or a compound walking foot?

I probably should not say this because I am not sure, but I think what you say about Tuff Sew machines, I have heard before.

Which also leads up to the question:  What was the Tuff Sew derived from, what machine?  Also, as I have already asked, are you referencing a walking foot or compound walking foot.

I guess the Tuff Sew is still sold?

All that said back to tension:  Have any of you bought thread that definitely contributed to thread tension problems?  I had a spool of thread that did, it could be sewn on different machines, but only for a little while, any little twist in that spool would show through in the seam results.  I should have kept that spool and labeled it as to what not to buy.

Mechanics all say clean the thread path frequently, they are correct, I have seen them get dirty or gum up or what ever, merely need cleaning.

Who ever thought sewing could be so technical.  Watch your thread, needle size, tensions (upper and lower), plus stitch length probably has been stated to vary tension.  I guess it does, degree depends on materials sewn, right?

Doyle

[Mojo]

The Tuffsew is sold under several different names and colors. It is also the Mini Thompson Walker and the LS1 Sailrite machine as well. The parts are all interchangeable. I used to buy my parts for the Tuffsew from Sailrite actually.

They are all walking foot / small bobbin machines based on a home machine ( small motor and removable foot pedal ). The problem is cheap Chinese engineering and manufacturing. While most of our machines now days are made in China the Tuffsews are made in different plants in different parts of the country under very sloppy conditions and poor quality control. The tolerances are terrible, the casting of parts bad and all of this leads to a very sloppy machine that is hard to fine tune and keep in timing. The fit and finish is deplorable. My bobbin winder broke the first time I used it. The top cover never fit and was drilled off centered so the top cover just laid there as a couple screw holes were stripped out. It would stay in timing for brief times but then need to be adjusted again. On and on and on.......

If I set one in front of you Doyle and you had the chance to take the covers off and really get down to inspecting them up close and personal you would know what I was talking about. You would also probably wonder how the hell I ever sewed anything on it. I still wonder this same thing myself.  :)

Chris

[sofadoc]

Maybe that's what they meant when they named it TUFFSEW.
Any sewing job that you do with it will be a tough sew. :D

You should've bought one named EZSEW. :D

I don't think any of those little machines are compound feed.

[Mojo]

No they are not compounds.

What I should have done is bought a Chandler from the git go. What a waste of money. But I will say this...........that Tuffsew taught me alot about machines. I could not work on my machines if it wasn't for that POS.

I can time a machine real quick now. :)   :o   ;D

Chris