Kenmore 2142 sewing machine won't zigzag.

If your Bernina 930 record sewing machine is experiencing issues with zigzag stitches and straight stitches, here are some troubleshooting steps you can try:

1. Check the needle: Ensure that the needle is properly inserted and not bent or dull. Replace the needle if necessary, making sure to use the correct needle type and size for the fabric you are sewing.
2. Adjust the stitch width and length: Verify that the stitch width and length settings are properly adjusted for the desired zigzag stitch. Refer to your machine's user manual for instructions on how to adjust these settings correctly.
3. Clean and lubricate the machine: A build-up of lint or lack of lubrication can affect the machine's performance. Clean the bobbin area and other accessible parts of the machine using a soft brush or lint brush. Apply a drop of sewing machine oil to the recommended areas as specified in the user manual.
4. Check the tension: Improper tension can lead to skipped stitches. Ensure that the upper thread tension is properly adjusted for the fabric and thread you are using. Consult the user manual for guidance on adjusting the tension correctly.
5. Test with different fabrics and threads: Try sewing on different fabrics using different types of thread to determine if the issue is specific to certain materials. This will help identify whether the problem lies with the machine or the materials being used.
6. Have the machine serviced: If the above steps do not resolve the issue, it may be necessary to have your Bernina 930 record serviced by a professional. There could be underlying mechanical issues that require expert attention.

It's important to note that the Bernina 930 record is a vintage sewing machine, and finding a qualified technician with experience working on older models may be beneficial if further repairs or adjustments are needed.

This video will probably be handy, although not quite your model, it should be very close. Generally, your machine should be able to do straight & zig-zag stitch without cams. Cams were usually for decorative stitches.

Kenmore 158 17550 Sewing Machine Tutorial

Parts: https://www.sewingpartsonline.com/kenmore-158-17600-sewing-machine-parts.aspx?sort.ss_cat_sort=desc&index=64

Manual: Kenmore 158 manuals 3

Hmm, I'm wondering if it has been cleaned and oiled recently. Older mechanicals require frequent TLC. Consult your owner's manual for cleaning and maintenance instructions:

Is your sewing machine mechanical (ie, not computerized)??? CAUTION--if your machine is computerized, do NOT proceed with the following suggestions.

If it is mechanical, have you cleaned and oiled your machine recently? Most mechanical sewing machine failures are because they have not been adequately and routinely oiled, the old oil has solidified and frozen the mechanics. I recommend Bernina oil or liquid Tri-Flow Synthetic Lube (or similar good quality sewing machine oil) for mechanical machines--do NOT use 3-in-1, cooking oil, WD-40, or the sewing machine oil from your grandmother's sewing basket. (I am not associated with any Bernina dealer.)

If it is in fact frozen, pick up a bottle of liquid Tri-Flow Synthetic Oil at the hardware store. Oil one or two drops in every oil hole (see your manual) and also every place where metal rubs on metal. But DO NOT oil any plastic gears, rubber, or belts. If it is still stiff or frozen, direct a hot handheld hair dryer into the top and bottom mechanism of your machine. See if that loosens it up. You may have to repeat.

Once your machine is working again, place a drop or two of good sewing machine oil as directed above. Be sure to use a small brush to clean the lint and dirt out of your machine, especially around the feed dogs and bobbin area. (Caution: Compressed air will sometimes force the dirt and lint into areas that cannot be cleaned.) And continue to use good quality sewing machine oil to keep it running. Recommendation: every time you change a bobbin, after 8 hours of sewing, or every six months if it is not in regular use.

If you can grab the hand wheel and move it right and left, then it probably needs a plastic collar that goes next to the left upper shaft bushing.
If not then the cam timing needs to be adjusted.

Depends on what stitch you intend to use. I do a lot of mending with a three step zigzag set to maximum width and minimum length -- see: http://www.picturetrail.com/sfx/album/view/24395076 A wide, short zigzag stitch is another popular choice, as is a straight stitch worked back and forth over the area: http://www.running-w-scissors.com/2014/01/tutorial-patch-mend.html

If you're just mending a seam that's come unstitched, a straight stitch or zigzag stitch similar to what's already in the seam is what you're looking for.

if all the dial are set correctly for the zig zag, and the machine
still won't do the zig zag stitch then it's possible that there is a
gear or cam inside the machine that is worn or damaged.
a sewing machine shop can tell you for sure.

it sounds like the machine needs to be checked at a sewing
machine shop to see what's wrong with the cam's or gear
that makes the stitches

The dial at the top right hand of machine ,turn it fron 0 to 1-5 for zigzag