Help with sewing tension

[piesoup]

Hi all, this is my first post here.
Been reading all the threads for the past few months and that's prompted me to dig out the sewing machine and have a go!

I have a Frister + Rossmann Cub 5 Super Stitch which is a sturdy beast. With a 100 needle, it'll pierce through anything! I'm using Coats Epic 80 thread and P5 PU Coated Nylons with P18 Heavyweight P.U. coated texturised nylon from Pennine Outdoor. Just some cheap fabrics to practice on. Hopefully they are close enough to VX21 and proper Cordura 500.

I'm stitching the thin P5 to the heavier P18, the thin P5 is on the top. Stitch length is about 2mm. I presume the lower thread tension is correct. If I jerk the thread, the bobbin falls about an inch to inch and a half...

My issue is, the upper tension seems to be too loose. The lower thread doesn't pull up into the layers which leaves the lower thread looking loose. I can increase the upper tension and all looks good for a while. Then balance between the upper and lower stitches becomes inconsistent.

I will post some pics tonight but I'm using the same colour thread for both so it isnt easy to see!

Any tips from you gurus will be much appreciated!

Thanks

[jeremy11]

First, check the manual for the machine and make sure you're threading it correctly - top and bottom.
Then, put the machine on zig zag (if it can do that) as its easier to see where the stitch is off balanced.
If the thread loops pull through to the bottom, the bottom is too tight (or the top is too loose).
If the thread loops pull through to the top, the top is too tight (or the bottom is too loose).

It usually takes a bit of fussing around with scrap fabrics to get used to all this.

[piesoup]

Thanks, I like the zig zag tip, will try that tonight. I have ordered some more colours so that will help too!

[ocary]

Check that the thread routing is smooth and that everything is clean.   I ran into two seemingly bizarre thread tension problems.  One was solved by cleaning the lint from between the plates behind the tension adjuster on my old Singer.  The other was that the thread spool holder I'd fashioned from a coat hanger for the same Singer had gotten out of place and the thread was jerking from the spool.

If you continue to have issues after checking the thread is routed correctly and cleanly, swap the needle for a new one - making sure you are using one that is appropriately sized for the material.   When I'm having issues, after a quick check of the thread routing and cursor, I swap the needle for a brand new one - on a setup that "used to work", usually my issues are from a dinged up needle.   If you continue to have issues getting setup, try a different thread.  My Consew heavy duty cylinder arm flat out hates the V92 thread I have and gives me nothing but problems.  Switching to a different thread solved the issues there.

And, yes, adjusting while using a zig-zag stitch tends to be a lot easier.

[piesoup]

I checked the routing was smooth, as far as I could see it is. I will strip down the tension plates and give them a proper clean out.
My needle is brand new, but I will change it for a new one just to be sure, who knows, I may have bent it slightly!

I've ordered two colours of a different brand thread too.

One question, speed shouldn't be an issue should it? I need to put a wedge under the pedal as its too easy to go max chat all the time, I need to be able to go slow!

Thanks again, I will follow up when I have done some more playing.

[dream4est]

Also check the following:
1. Bobbin case tension adjustment. A small screw on the bobbin case. Adjusts lower thread tension.
2. Bobbin wound correctly. Incorrect can cause problems too. Edit- Even the direction of how thread leaves bobbin and enters the case tensioner is important. On one of my machines it has to be clockwise or problems occur.
3. Presser foot pressure adjustment located on top of presser foot assembly.
4. Bobbin case assembly. Clean area free of lint and thread.

It sounds to me like you have too much disparity between upper and lower thread tension. They are averaging out to work somewhat, but inconsistent. Change the bobbin tension a bit first before trying the upper adjustment. Actually compare by pulling on the lower thread to feel the tension from adjuster. It should somewhat match the feel of the upper thread being pulled through the machine with presser foot up. The bobbin case having very light or very strong tension makes it hard to fine tune the top as they must match.

I was just having a similar issue on my straight stitch machine. I had it working only when upper tension setting was at zero. So after talking with Greg from Bolder Bikepack Gear, I decided to turn up the tension on my bobbin case. Now I have a nice even sewing tension with the upper knob set at about 3.5.

Also clean and oil your machine. It helps.

[piesoup]

Guys, thank you so much for the info, it will all help in my journey into the sewing world! Going through the points raised above, I found my issue...

My bobbin wasn't threaded correctly. In the manual, all the pictures are hand drawn and it wasn't clear. I didn't have the thread exiting in the centre of the tension plate, it was to the side under the little hook on the side of the plate. Which is how it looked in the picture.This worked fine for normal fabrics so I assumed it was OK. The tension still needs setting up but at least I've found it to be consistent. I will compare the tensions like you said dream4est, having a cat that wants to climb the Christmas tree means I can't devote ALL my attention to the machine!