Sewing machine help

[dikman]

My first thought was that the top tension is way too high (assuming there is a little tension on the bobbin). Is that top pre-tensioner necessary? looks like the lower slot in its guide will let you bypass it and just go straight down to the lower tensioner. Might be worth a try. Either that or back of the top tensioner so it's not doing much.

[Bugstruck]

2 hours ago, dikman said:

My first thought was that the top tension is way too high (assuming there is a little tension on the bobbin). Is that top pre-tensioner necessary? looks like the lower slot in its guide will let you bypass it and just go straight down to the lower tensioner. Might be worth a try. Either that or back of the top tensioner so it's not doing much.

Exactly what I thought when looking at that top stitch and I still am guessing as nearly everyone is saying, that is likely high. When I looked at how loose the bottom stitch was it got me thinking he probably has very, very low bobbin tension, regardless. I've messed mine up with that flat-line top stitch once or twice but not with that loose a bottom. A miss-directed bobbin won't get my bottoms that loose. Lint/dirt behind the bobbin spring?  Curious to find out but I think he's fighting it on both sides.  

Hey Tearghost, you probably know who I'm responding to but if not, you have an AAA-team member on machinery  on your issue now. I'd take advantage of Dikman if you are still fighting it. I'll to back to the bleachers and spectate for a while.

[dikman]

Bugstruck, thanks for the compliment but I'm a rank amateur, compared to others on here, when it comes to sewing machines!

On the other hand, I just bought a min-lathe (Chinese, of course) and spent the last three days stripping it and re-building it so it works properly.

[tearghost]

Thank you to all for your help, I got it running the way it should. The problem was all in the bobbin tension it was way to loose.

[Mark842]

You are threaded incorrectly on your top thread. I found this video for you

(skip in to about 20 seconds) . It shows very clear how to thread it and it will make a big difference in your tension. If you have adjusted the tension to get it stitching better how you have it now you will probably have to adjust it again after threading it correctly.

Things I've learned in years of sewing...always try to correctly adjust your tension by adjusting the top thread tension. You should seldom if ever have to adjust the bottom tension. I have machines I've been sewing on since the 70's that I have never touched the bottom tension on.

Think of the tension as a tug of war that you want no one to win. In your photo the top thread is winning the tug of war pulling your bottom thread to the top. Reducing top tension should resolve the problem. The incorrect way you are threaded is probably the cause of too much top tension. In a perfect stitch the knot for the lockstitch is in the middle of your project where it can not be seen.

Things that are important...the right needle size and thread size for what you are sewing.  If your needle is too big you will have trouble hiding the knot. If it is too small you will have flagging (what you are sewing will be lifted off the plate when the needle comes up) issues and thread fraying.

If your still having issues it would be helpful to know what size needle, thread, and how thick the leather you are sewing is.

 

[Bugstruck]

Actually Tearghost threaded it right and the video is technically incorrect. Either way would work fine and nothing a very minor top tension tweak would not cure between those two paths. I route my top threads differently sometimes depending what I am doing. Fully intentionally with the results I want. Don't do it often and not where I'd baseline a machine or recommend a newbie start though. Once one has a good grip on tensions you can play around a little and sometimes  a combo the machine likes is found. My 4500 for example doesn't get the 360 degree lower tension wrap on 138 or 92. Needs it on 207 and up. If I drop that wrap to 180 I often don't have to adjust upper tension much. Bobbin tension maybe, that needs some snugging when the thread gets light. 207 and up I leave it alone. Most of my machines don't need bobbin adjustment across the thread weights they handle but those that are wider spectrum sometimes do and sometimes the sewn material asks for a loose or tight stitch upper adjustment alone can't achieve without unbalancing the stitch. Rare but occurs. Usually at the extremes of material.

Great find on that video. one of the best threading videos I have seen. You did better than I did. I told him his correct path looked wrong right out of the gate and had to correct that comment. Glad he got it sorted out.