Uneven Stitches Singer 15-91-Help
 

Hi, first off let me say I am a Intermidiate/Advanced beginner on sewing machines.

Next I have noticed uneven stitches when I sewd on thick wool with Coats and Clarks Mercerized Cotton thread (I think it is old thread) and a Schemetz denim needle.

Furthermore, I noticed uneven stitches when I sewd on thin poly/cotton(?) fabric with the same thread and a Schemetz 70/10 needle.

The last instance I want to mention is uneven by turning into little stiches going over a thick seam (which may be normal, idk).

Also I should mention as I'm still a beginner my speed isn't consistent. As an example, sometimes I speed up, then slow down quickly.

Smaller stitches over a bumpy seam is normal, a more even feed needs to be sorted out to get correct stitch length; there are small plastic even-out tools, and some brands (my Bernina has at least) have a longer foot to deal with sewing over flat felled seams on jeans. You can use an empty needle package too. Speed should not affect stitch length, unless you use a darning foot or free motion.

Size 70/10 needles is for fine fabrics and thread has to be accordingly, so double check that the needle hole is large enough for the thread to run through it easily.

These are factors which are very basic, but even though I know them all very well, I need a reminder now and then and go through the full check list.

Needle in the correct way; clean bobbin / feed dog area; a thread might be caught some where; check tension spring in the bobbin case; check for correct bobbin type and evenly wound bobbin; check that the top tensioner releases and grips the thread as it should. Check behind the face plate too, just in case. Also check for burrs in the needle / needle hole even if it's brand new, it can happen with the best brands even if it's a rare thing.

If the old thread is very sticky and dirty it might act up, but the general advice for throwing out old thread is mostly because it can become weak as the decades go by (not always the case, but if so it will snap). The second is old cotton thread is often thicker than todays standard sew-it-all polyester; which means some machines needs to have bobbin tension adjusted and it can be a bit cumbersome. I need to use a varying range if thread thickness from lighter than sew-it-all to top-stitch and I just have to live with adjusting the bobbin tension now and then.

Stitch length can be affected if some of the parts from the stitch length lever / knob to the feed dogs are gummed up. It might need tentative oiling the next few days to have it sorted out.

I can't think of anything else at the moment.

Mickey, thank you!! I will try at least some of those. One thing I've noticed it's my top thread gets tangled with my bobbin thread every once in awhile and the top thread breaks off, even though the tension is correct. Maybe this is part of the uneven stitch problem? I hope I didn't end up with lemon of a Singer. But at least it sews MUCH better than my Pfaff Expression 2.0. :D

I don't own a model 15 my self, but I have test driven one or two. I have a 99, a 66 and a 201 and the bobbin mechanism is a bit different on thes. Even so, I dare say it's only a question of fine tuning and getting to know your machine better, it should sort out any stitching issues. Model 15 has a reputation of being very forgiving when it comes to thread and tension, but they often need a bit of tending to when they are taken out of years of storage and no use. The feed on these old machines is usually excellent.

Mickey2 gave you very good information. I have a 15-91 that in finally got sewing well just last month. The first two things I would highly recommend you do are 1)make sure the needle is in correctly (flat side to the left) and 2)bobbin case is threaded correctly (thread should come off the top of the bobbin in a counter clock wise direction).

For thick seams you will need something behind the foot to help keep it level like Mickey2 mentioned. I use a thing called...a Jean a ma Jig (or something like that).

I had so much trouble w/my machine for more than a year and it was ALL because my needle was in wrong. Maybe yours will be an easy fix too. I am now having so much fun sewing again because my machine works properly.

Here's a link for how to use a seam jack, jean-a-ma-jig, jeans jack. http://shesasewingmachinemechanic.bl...re-sewing.html

Another thought... It may feed better with tighter presser foot tension -- the round post on the top/left of your machine.

Make sure it isn't set for free motion/darning. There are two settings, the pressure at the top and the feed dogs position underneath. Some have some kind of pop up at the top and some just have an adjustment nut. The feed dogs may or may not have a screw under the machine depending on the machine. If it is a non Singer it may have a lever or buttons near the post. Check a manual to be sure how to adjust them. In any case, CHECK YOUR MANUAL BEFORE YOU FOOL WITH iT.

If I am reading your post correctly, the problem happened with different needles and fabrics but the same thread. Have you tried different thread? My 15-91 sews like a champ with many different types of thread but throws a fit when I use Isacord thread. Let us know what you figure out!

When mine does that it generally needs a new needle. It isn't usually the tension for me. Also on a 15, the flat side of the needle goes to the left, just like a Featherweight. The 15 is a very good machine. Get out the manual and DON"T GIVE UP. Rest between, if needed, but your machine just needs a little help. Also, be sure you are using a good 15 bobbin, not a 66. There is a difference and your machine can tell. The 15 is totally flat on top and the 66 has a slightly rounded top. It happens.

Yes, you are correct. Sorrowfully, a lot of the thread I'd use is 500 miles away from me (since we are moving). Thanks for the advice though. I may have some more spools thread here though, I'll look. :)

Donna,
I believe I did use new needles. At least I hope they were, as they were in a needle package. I'm not too good about throwing away needles like I probably should, lol. But I think these were new. Donna, thanks for the great encouragement I will continue working on it. :) I do think I have an incorrect bobbin, I'm trying to get a vintage one that matches a picture in the 1950's 15-91 manual. Perhaps this is the problem. Oh, there are so many possibilities! Lol.

I used to throw away all needles I hadn't bought my self, maybe unless they looked brand new in a packages. I discovered some sell needles individually from a large package, they just pin them in a piece of fabric and into a paper bag. Either way, I relalized I probably had threwn out brand new needles because they weren't in what looked to me original packaging. I found this neat advice to run the needle over the tip of your nail, if it catches it's worn and if it's smooth it's still fine. Running it over a nylon stocking or similar will catch the slightest of wear too.

In hard times when new needles were hard to come by, they ran the tip of the needle over a fine honing stone to take the burr out of the metal, and they could stitch away with the same needle. I'm not that frugal, but I try not to throw out perfectly good needles, just because I didn't buy them my self. I haven't seen them in a while, but I used to buy a type of needle with a ceramic tip, or some kind of extra hard metal, they were made to last much longer than regular needles. It would be such a waste to throw them out just in case. Does anyone find checking the needle tip for burrs and wear reliable? So far it has worked for me.

Ladies, I am excited! Today I am getting new needles. Schemetz sharps size 14 and Singer titanium needles size 14, 16, and 18. I am also getting new thread to try. Aurafill, and Mettler. Later I might try Masterpiece quilting thread.

I solved the problem! After hours of adjusting the tension and pressure foot pressure, my stitches are now even! I loosened the bobbin tension, tightened the upper tension, and loosened the pressure on the fabric.

Uneven Stitches on 15-91
 

I hope someone has a suggestion that will help. I am using a 15-91 in good condition to sew vinyl for boat seats. At a slow speed I get the 6 stitches per inch I want (and the machine it set for). However, the faster I sew a seam the shorter the stitches get. Is there an adjustment somewhere that I am missing?

Haven't had that problem myself even at full speed so i'd try adjusting your feed rate :thumbup:

Hooligan
Thanks for the reply....By "feed Rate" do you mean how I pull material though the machine or something else?

Yes DVM, i meant how the fabric is fed through the machine. Don't pull the fabric, just merely guide it through and should be good. :thumbup:

The only adjustment, that I can think of, would be to change the pressure regulating thumb screw. I always forget which way, so would practice on some scraps.

Since you are sewing vinyl, you didn't say what needle you are using, or what foot, or if you have tried sewing with thin paper against the feed dogs and the presser foot. Years ago, I made some things with fabric backed vinyl. I read that a roller foot was good or a teflon foot. I was able to get a roller foot at that time, but not a teflon one. Also, to put scotch tape on the bottom of a regular foot. Another suggestion was to use a leather needle. Putting tissue paper (the thin type for wrapping presents) over and under what you are sewing, was also suggested.

There are several places on the internet for tips for sewing with vinyl.
Janey - Neat people never make the exciting discoveries I do.

I have been sewing quite much vinyl with my Singer 201, and the feed system is similar to the Singer 15-91.

I should look for the following:
1) Reduce thread tension (both bobbin and needle thread tension).
2) Increase needle size in order to reduce thread tension.
3) Increase presser foot down force.

This was still not sufficient for me in all cases, and then I discovered, that a changed presser foot could help you a lot. You can find information about that in this video: https://youtu.be/rBIulDuhDDs

You may also be able to change the feed dog timing, because it can help you when sewing heavier fabrics on domestic sewing machines: https://youtu.be/rBIulDuhDDs