Why am I Still Getting Small "Puckers" on My Seams?

[stitchit]

Since I have been in the canvas fabrication business, I have "always" been frustrated with the fact that when I get done sewing a long stitch on, for example, a mooring cover, the stitch line always ends up having small but definite puckers, which will come out fairly easily when "pulled" on each end of the stitch line.

The main problem comes in when I want to sew the mooring cover side to side, instead of fore to aft. Due to the fact this is happening, I pretty much have to sew the center seam for to aft, to try to eliminate the problem.

Can anyone tell me what it might be caused from? I'm not sure that the machine did it when it was new, but it has for a very long time. Could it be that the presser foot needs to be adjusted?

I'm using Tenera Gore-Tex thread, winding my own bobbins

Here's a quick video clip of the issue:




Thanks,

Chris

[Mike8560]

I have a livbt foot tension on my machine I can actually stop the material fom moving if I gold it ligbtlly. Sound like maybe the machine is pulling the fabric though and at the same time the thread. Is trying to hold it back.

[stitchit]

You're thinking the presser foot has "too much" pressure? I definitely can't pull the material out of the foot when the foot is simply "resting" on it.

[bobbin]

The first thing that crossed my mind is the the thread tension is too tight, or maybe the fabric in use is marginally too light for the machinery you're using.  Your comment about not being able to remember if the machine did that when you first got it makes me wonder when you last cleaned out the tensioners and really went back to rework the tension settings.   I know that happens to me regularly.  I routinely adjust the tensions and over time they get tighter and tighter and the seams don't lie flat or have the proper "give".   I find starting from scratch is very helpful; I did that with my new machine when I began the slipcovers and it made a big difference in the overall quality of the stitching. 

I wasn't able to see if the line of stitching in your picture is running along the selvedge grain or cross grain (from selvedge to selvedge).  There is more stretch in the goods along the selvedge and I see the "puckering" more on long join seams on awnings/canvas blanks than I do when I'm stitch across a panel.  As you mentioned it's easy to "pull them out" by tensioning the seam. 

If you feel like experimenting here's what I'd try:
1.)  shorten the stitch length a bit
2.)  loosen both the top and bobbin tensions.  Remember that you're trying to allow the machine to feed more thread along the seam, but you still want those threads to be balanced properly. 
3.)  The "acid test" for proper tension adjustment is to stitch a sample on the true bias and have the seam lie flat, not puckered or wavy. 

[stitchit]

When u say true bias, are you saying at a 45 degree angle? I have actually taken the tensioners apart about once each summer for about the last 4 years.

Thanks,

Chris

[bobbin]

Yes, "true bias". 

[fragged8]

there is quite a few posts on this in the past as I have been fighting
puckers on and off for a while.

yours looks like a tension problem as has already been said.

just try this first, cut one piece of material sideways off the roll
of fabric, and one cut length ways then sew them together and see what
you get ...

if still puckered..

set machine to maximum stitch length

back way off on the bobbin tension and top tensions.
do the drop test on the bobbin. ( do you know this ?)

check the force of the take up spring, if too hard then it could
cause puckers by really tugging on the tread when knot forming.

i would also check the thread release finger is actually doing its job.
the thread is held back while the knot forms and the bobbin case is then flicked
by the finger to release the thread and knot. I had some problems because
mine wasn't working correctly. It's an easy thing to miss.

if still puckering post up a video of your bobbin mechanism in operation

Rich

[Mojo]

I would do what Bobbin said first before looking anywhere else.

Tenera on its own has been known to cause puckering in some fabrics. I had this issue with some light canvas material and after adjusting the tension it took care of the puckering.

The other thing to watch is how your feeding the material through the machine.

Chris

[fragged8]

isnt it recommended to slightly adjust the timing
when using tenara ?
also a smaller needle and sometimes turn the needle
a tiny amount to form a better loop ?( depending on machine)

Rich

[stitchit]

Not sure about timing.  But I do use the "mr"
Needles recommended.

Also.  It does do it with polyester as well

[stitchit]

Well, here's an update-- I adjusted tensions as suggested. The knot is "just" below center. Not really on the bottom of the stitch however.

The outcome-- Amazing! Looks to have taken care of it.  ::)

Talk about feel like an idiot! I've never had it clear up before by just adjusting tensions. Hopefully it will stay this way! Thanks a million gang!!

Chris

[gene]

Chris,

We don't talk about feeling like an idiot on this forum since we have all been there. For some of us at least once. For others, well...

I always tell my kids, "Isn't it interesting how doing something is a lot easier when you know how to do it?"

gene

[stitchit]

Ha ha ha. Great point Gene!

[Mike8560]

did you shoten the stitch length also as bobbin said? me id think that could cause them

id lenghten also . ::) but glad its all good now

[stitchit]

I actually hadn't changed the stick length yet.  You're saying the longer the stitch the better?