Two ways to card fiber, two very different results
When you send fiber to a mill for carding, you will be asked: do you want roving or batts? Both start on the same drum carder, but they come off differently and behave differently in your hands. The choice affects your yarn structure, spinning speed, and what you can make with the finished product.
How roving is made
After the drum carder creates a thin web of aligned fibers, that web is condensed into a continuous rope. The fibers are roughly parallel – not perfectly aligned like combed top, but oriented in the same general direction. The result is a dense, smooth rope typically 1 to 2 inches in diameter, wound into bumps or braids.
Mill-produced roving (sometimes called “roving off the card” or R.O.C.) is different from hand-carded roving. The industrial drum carder processes fiber faster and more consistently, producing longer continuous lengths with fewer thin spots.
Some mills also offer pin-drafted roving (P.D.R.), which runs the carded roving through an additional drafting step. This further aligns the fibers and creates a lighter, airier preparation that is easier to spin. Pin-drafted roving costs slightly more but produces smoother yarn with less effort.
How batts are made
Batts come off the carder as flat sheets rather than being condensed into a rope. The web is peeled off the main drum in a wide, fluffy layer – typically 12 to 36 inches across and a few inches thick. The fibers are less aligned than in roving, oriented in multiple directions within the sheet.
Batts can be layered for thickness (multiple passes through the carder stacked together) or blended (different fibers or colors fed through together). This makes batts the better choice for custom color blending – a mill can card layers of dyed fiber into a single batt with beautiful color transitions that would be difficult to achieve in roving form.
How they spin differently
This is where the practical difference matters most:
Roving produces worsted-style yarn. Because the fibers are roughly parallel, drafting is easier and the resulting yarn is smoother, denser, and stronger. It shows stitch definition well, making it good for cables, colorwork, and structured patterns. Worsted-spun yarn is also more durable – better for socks, bags, and high-wear items.
Batts produce woolen-style yarn. The multidirectional fiber arrangement traps more air, creating yarn that is loftier, lighter, and warmer for its weight. Woolen-spun yarn has more halo and a softer hand, but less stitch definition. It is ideal for warm sweaters, shawls, blankets, and anything where insulation matters more than crisp stitch patterns.
| Roving | Batts | |
|---|---|---|
| Fiber alignment | Roughly parallel | Multidirectional |
| Yarn character | Smooth, dense, strong | Lofty, warm, soft |
| Best for spinning | Worsted draw | Long draw, woolen |
| Stitch definition | High | Low (more halo) |
| Durability | Higher | Lower |
| Warmth-to-weight | Lower | Higher |
| Color blending | Limited | Excellent |
| Felting projects | Possible but less common | Ideal |
Beyond spinning: other uses for batts
Batts are not just for spinners. They are the standard preparation for:
- Wet felting: Batts lay flat and felt evenly, making them perfect for felt fabric, vessels, and wearables.
- Needle felting: The multidirectional fibers lock together easily under a felting needle.
- Quilt batting: Wool batts make excellent natural quilt filling – breathable, temperature-regulating, and mold-resistant.
- Dryer balls: Tightly wound and felted wool batts replace dryer sheets.
Which to order from your mill
If you are a hand spinner making yarn, your intended project should drive the choice:
- Making socks, mittens, or anything that needs to hold up? Roving.
- Making a warm, cozy sweater or shawl? Batts.
- Want to blend colors or fiber types? Batts.
- New to spinning and want the easiest experience? Roving (or pin-drafted roving if the mill offers it).
- Planning to felt? Batts, always.
If you are not sure, ask your mill what they recommend for your fiber type. Some breeds card better into one form than the other – a long-staple fiber like Romney makes beautiful roving but can be tricky in batts, while a shorter fiber like Corriedale works well as either.
Pricing is usually the same for roving and batts from the same mill, though pin-drafted roving may cost slightly more due to the extra processing step.
Find a mill that offers what you need
Use our directory to filter mills by services. Look for “carding,” “roving,” or “batts” in the service listings. Many mills offer both preparations – but it is worth confirming before you send your fiber.