Cannot sew through heavier fabric - Sewing Machines

The size of the needle is determined by the fabric and thread you are stitching. Heavier fabrics and threads will require larger needles. Finer fabrics and threads will use smaller needles. Silk would probably take a 70/10 or smaller. Regular woven cotton would probably use an 80/12 or 9-/14. Heavier fabric like light-weight denim would probably take a 100/16 or a denim/jeans needle.

SCHMETZ Household Needle Chart SCHMETZ Needles

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Depends how thick the material is. Most mechanical machines will sew thicker fabrics, however, if the needle is unable to penetrate the fabric, it could damage the machine. Be sure to use a heavier, sharp needle.

Needle size really depends on the fabric you're sewing. Fine needles are used for light, fine fabric. Heavier needles are used for stiffer, coarser fabric. Very heavy needles are used for things like denim, leather and other very thick, coarse fabrics.

The actual size needle depends on what fabric you are sewing. Lower numbers for light fabrics and higher numbers for heavier fabrics. I use mainly 10, 12 and 14 for normal cottons.

buy Singer brand. Use size 9 for lightweight silky-type fabrics, 11 for ordinary cottons, 14 or 16 for heavier fabrics like denim. Use 'ball point' for knit fabrics, 'sharp' for woven fabrics but 'universal' will work on both. You can always ask the fabric shop ladies, especially if you bring a bit of the fabric that you will be sewing on.

a heavier drapery fabric is going to require a needle & thread for that specfic fabric

yes, & the thread may not be the right kind for the fabric, also the tension would have to be adjusted to meet the needs of the thread & fabric

Not sure if I can help, but it may have to do with the heavy thread as well as the fabric and needle combination. If the fabric is thick or tightly woven, be sure to use a brand new sharp needle. (If the fabric is tightly woven (like Batik), a thicker thread may present a problem.) In your case, if using a heavier thread, perhaps a top-stitch needle would be beneficial since it has a bigger scarf to protect the thread. With the heavier thread in the top, the top tension will need to loosened. BUT, if you loaded the heavier thread in the bobbin, the bobbin tension will need to be adjusted to accommodate the thread thickness. However, remember that if you adjust the bobbin tension for this project, you will most likely need to readjust it for the next project using different materials.

FWIW, if the machine still works fine with regular fabric and thread, then you'll know that the issues revolve around the current project.

Understanding Thread Tension Threads

How to Achieve Ideal Sewing Machine Thread Tension Threads

Sewing Lesson 10 How to Fix Tension on Your Sewing Machine

Most domestic sewing machines will not handle heavier thread than the standard 50 weight. I'd suggest you go back to regular polyester sewing thread and use a 110 or 120 size needle to cope with the heavier fabric. Sew slowly and give it some help on the flywheel when crossing a seam allowance. Maybe stitch each seam twice, with a 1mm gap between to give it strength.

If you need to use the heavier thread to do the job then you will probably need an industrial sewing machine that can handle that grade of fabric and thread. Something like a Singer 20U machine in a table with seperate motor drive.

Fabrics like Canvas, ticking and PVC for exterior items are generally going to be beyond the functionality of a domestic machine and you can damage the machine, particularly the timing by trying.

needle size depends on the fabric you are sewing. #11 is a fine needle, for lightweight fabrics and is basic. Heavier weight fabrics, like denim, require heavier needles#14