50 weight thread is a versatile, medium-fine thread ideal for piecing quilt tops, detailed machine quilting, appliqué, and general garment sewing, creating flat, crisp seams and subtle stitch definition without adding bulk, though it's also strong enough for machine embroidery and binding. Its versatility comes from being thin enough for delicate work but strong enough for construction, making it a quilter's staple.
Medium Weight Threads
These are the types of threads that you will most frequently find, most often 40 or 50wt. They can be used for most construction, quilting, machine embroidery, sergers, and general purpose sewing.
When discussing weight of thread, the smaller the number, the thicker the thread. The weight is determined by how many meters of thread it takes for a skein to weigh one kilogram. In this case, the 40 wt thread is slightly thicker (heavier) than the 50 wt thread.
A higher number like 50wt indicates a thinner, lighter thread. This means 30wt thread will be more visible, and create a bolder stitch. 50wt thread will be less noticeable and create a more delicate stitch. An easy way to remember which is thicker is “thirty is thicker” and “fifty is finer”.
50wt Thread
This weight thread is the most popular weight used for piecing quilt tops as it is thin enough to not add bulk to your seams and strong enough to hold them together. It is also used by many for all kinds of quilting including stitch-in-the ditch, straight-line and free motion.
When using a 40 weight thread, use a size 80/12 needle. If using a thread finer than a 40 weight, such as a 50 weight, use a smaller needle size such as 70/10. Micro threads use needle size 65/9 or 60/8.
The Golden Ratio (approximately 1.618) is used in quilting to create visually harmonious designs, guiding decisions on proportions for borders, sashing, and block layouts, often linked to the Fibonacci sequence (e.g., 3, 5, 8, 13-inch strips) to achieve natural balance and aesthetic appeal that feels inherently pleasing to the eye, making quilts look more balanced and intentional. Quilters apply it by multiplying a measurement by 1.618 (or 0.618) to get the next size for elements like borders, or by using Fibonacci numbers for strip widths.
Gutermann Cotton Sewing Thread is a fine 50 weight cotton thread but strong with a silky finish for users who prefer to sew with cotton. Suitable for hand or machine sewing, Gutermann Cotton Thread is a 100% longstaple mercerized cotton sewing thread.
Picking a hue that has chameleon ability seems to work best for scrappy quilts or quilts with clear light, medium and dark fabric. I like rust, off reds, warm browns, mustard, smoke gray and taupe best. From my experience, these thread colors change as they pass over the quilt to blend rather than distract.
Uses: Needle Turn Applique, English Paper Piecing, Hand Piecing, Bobbin and Machine Lace, Machine Applique (Straight Stitch, Zig Zag, Blind Hem, and Blanket Stitch), Machine Embroidery, Dense Machine Quilting, Subtle Machine and Longarm Quilting, Basting, Whole Cloth and Micro Quilting, Dense Background Designs.
Polyester threads are ideal for quilting as they have almost no lint, don't shrink, come in an array of colors, can be cleaned by any method, and are colorfast. To choose a color of thread for quilting, audition several on top of your project.
The first number follows the Gunze Count standard and indicates the thread size. The larger the number, the finer the thread (a 50/2 will be thinner than a 30/2). The second number indicates the number of strands, or plies, twisted together.
Here's Why You Shouldn't. Quilting thread is often thicker than regular sewing thread - typically 30 or 40 weight, compared to the standard 50 weight of piecing/normal sewing thread. This extra thickness can impact the accuracy of your seams, especially in intricate piecing, where precision is crucial.
But we also want to touch on one of the most common questions we get asked: will polyester thread cut into the fabric? The short answer is no, polyester thread is safe to quilt with and won't damage your fabric.
Kevlar Thread. Kevlar(TM) thread is one of the strongest and most fire retardant commercially available threads. It is about 2.5 times stronger than nylon or polyester, has almost no stretch, does not melt, and decomposes at 800F.
The general rule is that if you are using lightweight fabric, use a lightweight thread. If you are using cotton, a middle weight like 40 or 50 wt thread, works very well. Thicker fabrics like denim, may require an even thicker thread.
Best Thread Weight for Hand Quilting
For traditional hand quilting, try using 50 wt cotton. It is strong, visible, and glides nicely through the layers. Many modern quilters prefer big stitch quilting for a more decorative look.
It is designed to blend seamlessly into the fabric, making it ideal for creating strong, invisible seams. On the other hand, quilting thread often features a higher sheen and is available in both cotton and polyester, making it suitable for visible stitching that adds to the quilt's design.
40 wt.: The "Show Me" Weight
thread. It's thick enough to create visible, dimensional stitches without being so heavy that it overwhelms your fabric or quilt pattern. This is also the traditional weight for hand quilting and a favorite for machine quilting when you want your stitches to be part of the design.
70/10 – 100 weight threads. 80/12 – 50 weight threads. 90/14 – 40 weight threads. 100/16 – 30 weight threads and thicker.
Project Purpose: For projects requiring flexibility, choose polyester. For projects focused on tradition and appearance, go for cotton. Durability Needs: Polyester's strength and resistance make it better for high-stress seams or items that will be frequently laundered.
Gutermann Machine Quilting Thread is strong but fine with a silky luster. Ideal for machine quilting and machine and hand sewing.
Dirty quilting refers to a fast, fun, and forgiving style of quilting that intentionally ignores traditional precision, focusing on using up fabric scraps quickly without worrying about points matching or perfect seams, often using techniques like "stitch and flip," layering flannel with clips, or creating "ugly" fabric quilts for a unique, scrappy look. It prioritizes speed, creativity, and a relaxed attitude over perfect technical execution, making it great for beginners or quick projects like lap quilts.
The hardest things to sew involve challenging fabrics (like leather, slick synthetics, sheer silks, or heavily beaded materials), complex garments (tailored suits, wedding dresses, corsets), or intricate techniques (fitting, curves, buttonholes, zippers) that demand precision, patience, and specialized tools, often combining these elements for peak difficulty.
The three traditional quilts a woman should make before marriage, as popularized by Margaret Atwood's novel Alias Grace, are the Tree of Paradise, the Flower Basket, and the Pandora's Box (sometimes a Double Wedding Ring), each teaching essential skills for homemaking, storytelling, and household management through their intricate patterns.