Invisafil Thread on the Bernina Q20

I have been a big fan of 100wt Invisafil Thread from Wonderfil Threads ever since I did Bethanne Nemesh' online workshops. Up to then I had been using Invisafil mainly for stitch-in-the-ditch but was encouraged through those workshops to give it a go for background quilting.

Usually I have no tension issues with the thread having understood that it needs a lower tension on top and maybe a little bit of an adjustment on the bobbin tension. I recently started another background filler project using the same orange thread that I had previously used on an earlier wall hanging. I had a vague idea that I had some issues with the thread but once the project was finished I obviously put that out of my mind.

Started last week

Nice, but not good enough. I struggled through the quilting as my tension just was not right. It was somewhat too high pulling up the white Decobob 80wt bobbin thread to the top, leaving some ugly little knots. Remembered that I struggled with this previously and undertook to really look into this. Do not have that issue with a white Invisafil on the top so was aware that the colouring also may play into this. So spent hours last week to take all this out and rejuvenate the fabric (steaming it, spraying it again with water and letting it all dry in the wind)

First thing I did was ordering a cone of thread as I was still using a small spool that I had used on the previous project which drove me crazy as it kept catching on the rim. So, set that up

The thread is so fine you can hardly see it. Put a new needle in (80/12 Microtex) and gave it a whirl with the preset that I had entered previously on the machine (tension sitting at 2.25, bobbin tension at about 180). This is what I found:

- no more issues with the thread snagging on the rim ✅

- tension way too high, i.e. could see the white bobbin thread looking up through the holes and the stitch looked not that nice and did not feel right to stitch suggesting that it was being stretched.

- lowered my tension down, initially all very structured, going all the way down to 1.5; found that the thread was definitely too loose at that setting as I could see it wobbling as it was laid down

- strangely enough, was also getting orange pokies on the back.

This is were my more structured approach left me and I started to play with the bobbin tension. Normally bobbin tension for the Bernina Q20 is set at 220 however I have found that this needs to be adjusted at times for different threads (and different colours of threads). I had read somewhere on the net that people dial down their bobbin tension for Invisafil so I started lowering my bobbin tension. This is when it all got a bit messy. Must say one should be really relaxed going through an intense tension exploration...it can really drive you crazy when you loose sight of what you are adjusting in what order. When I had the bobbin tension quite low ( approx. 160) my tension was completely out of whack. My upper thread was still too tight while at the same time producing orange pokies at the back. Spelled complete mismatch to me on both fronts (top and bobbin thread) and after I had gathered my thoughts, I went back to the top thread...this time going by feeling more than anything else. My thread felt good to stitch at 1.75. Anything lower than that and the machine arced up, i.e. stopping and giving me a tutorial about threading! So decided to run with that and adjust my bobbin tension to tackle the pokies in the back. This took a while as just minute changes on the bobbin tension can change how the top appears. 

Also should say that I tried different needles while I was at it, first a 70/10 and then even a 60/8 needle. Must say I did not observe all that much of a difference in how the thread behaved, so this was definitely an adjustment issue. Eventually arrived at a bobbin tension of 180 -190, top tension at 1.75 with a 70/10 Microtex needle:

- top thread felt good to stitch, i.e. was not stretched and buried into the fabric; while I could see the white dots coming up while stitching, this disappeared instantly as I went along; had no ugly little white knots coming up every 5 seconds when hesitating in my stitching

- the back looked half decent; every now and then the orange would show slightly but I decided that this was negligible and possibly had to do with my speed or movement.

This is what this looked like

Hard to believe but this took well over 2 hours of needle changes, bobbin and top thread adjustments, so definitely something you only want to do when you are in a bit of a Zen mood.

Went on to stitch out the section of the quilt that I had taken out

Tension was fine, i.e. felt good to go along which meant that I could solely concentrate on the stitching. May have one spot were I hesitated for way too long so the white shows a tiny bit, but that was ok as I knew that the tension was otherwise alright.

The back

Bit hard to see but almost no pokies except for the odd spot here and there. Now that can probably be attributed to how I stitched the shape but could also point to the quality of the fabric. While nice, the backing fabric is just that little bit more loosely woven than the solid front. 

So what am I taking away from this little tension exploration today...STICK WITH THE PLAN and systematically go through the variables. Even better still...take notes as you do it.

But seriously, with a bit of patience and thinking through of what is happening you can fine tune just about any thread.

Karin