Problem with reverse stitch tightness on Singer industrial

[AlainaZ]

Hey folks,

I'm having a problem, hoping someone can help. In forward stitching the tension is perfectly balanced, but when I reverse it the upper thread is very tight. Any ideas why this happens, and what I can do about it? The forward/reverse stitch length balance is perfect, so I've eliminated that as a reason. This is on a Singer 591, but if you know about this issue on any machine I'll be interested, since it's a problem I encounter a lot in the machines I work on (this case is just particularly bad).

A video of the issue is here: https://youtube.com/shorts/jY-ETcKG2AM?feature=share

I used a lightweight cotton so that the issue would be obvious, but it bunches with lightweight leather too. 
Machine: Singer 591 D300AD

Thanks,
Alaina
 

[kgg]

12 hours ago, AlainaZ said:

In forward stitching the tension is perfectly balanced, but when I reverse it the upper thread is very tight. Any ideas why this happens,

My take on what is happening. I watch your video and the pressor foot is not applying any tension to the material to hold it in place. When sewing in reverse you are basically sewing a second thread into the same hole that was previously created. Without the presser foot holding the material in place the material can lift up between the fingers of the presser foot which creates bunching as well as a bad stitches, etc. The pressor foot needs to be adjusted down farther to the bed or by adding more pressure at the presser foot adjustment knob to hold the material in place.

kgg 

[trash treasure]

I think we're going to need a little more info - Can you take another video, of the upper thread path as you sew.  It might be that the take up spring is way out of adjustment, or something . Are your tensions balanced to begin with - Upper tension too tight vs. bobbin, etc?  Foot pressure too light, it looks pretty minimal?

Could be any number of things.

I see Kgg has just answered - Check the foot pressure, as that might be it - Often something very basic.

Edited May 31, 2022 by trash treasure

[sandmanred]

Please post a photo of the bottom of your presser foot, I'll explain why.  Here's my story and theory about what may be happening.

I had a similar presser foot to the one in your video.  I could get nice balanced stitches.  But then when I'd change to another foot like a roller foot or zipper foot I had to back way off on the top  tension.  And then take the tension back up when I switched the foot back into the machine.

I determined that with the foot like yours and going forward as the stitches get pinched between the presser and the needle plate and thus requiring higher tension than say a roller foot or zipper foot.  In your case when you go in reverse the stitch just made is not under the presser foot so the tension set for going forward is now way to high for going in reverse.

Here's a picture of what I did to resolve my problem.  I filed a small relief in the bottom of the the foot like yours so that the stitch being formed doesn't get pinned to the needle plate by the foot.  Now I can switch feet with no tension adjustments.  I think this same relief could solve your problem.

[Constabulary]

I would check the foot bar height, make sure it has full contact with the needle plate when lowered. I would also check the height of the feed dog (maybe set too low?) and the condition of the under side of the presser foot as mentioned before. My 2 cents

Edited June 1, 2022 by Constabulary