The stitch finger needs to be switched from N (normal stitching) to R (rolled hem) before a rolled hem will form correctly. This is the most common cause of a rolled hem not forming - check this before anything else.

• Locate the stitch finger lever or dial - it's usually found in the looper area and marked N and R
• Make sure it's switched to R before attempting a rolled hem
• Check your manual if you can't locate it on your specific model
• A small number of machines have a separate rolled hem lever or selector in addition to this - check your manual to confirm what your machine requires

Tension settings for a rolled hem are very different from standard overlocking. Getting the tension right is the key to a clean, tight roll.

• The lower looper tension typically needs to be significantly tightened to pull the fabric edge into a roll
• Start with the lower looper tension set high, test on scrap and adjust gradually until the edge rolls cleanly
• The upper looper tension may also need adjusting - refer to your manual for recommended starting settings for rolled hem on your machine
• Make small adjustments one dial at a time and test after each change

Stitch length has a significant effect on the finished appearance of a rolled hem.

• A shorter stitch length gives a tighter, neater rolled hem - try setting to around 1-1.5mm as a starting point
• Adjust from there and test on scrap until you're happy with the result

Thread choice makes a noticeable difference to the quality of a rolled hem.

• Fine thread works best - woolly nylon or fine polyester in the upper looper gives a beautifully smooth, full finish
• Thread that's too thick can prevent the edge from rolling cleanly and make the hem look bulky

Not all fabrics are suitable for a rolled hem - the technique works best on certain fabric types.

• Rolled hem works best on lightweight woven fabrics such as chiffon, organza, fine cotton and silk
• Very thick, stiff or heavily structured fabrics won't roll cleanly - rolled hem is not suitable for all fabric types
• If the fabric isn't rolling despite correct settings, it may simply not be suitable for this technique

Always test on a piece of scrap of the same fabric before working on your actual project. A rolled hem often needs a little fine tuning to get right - don't be discouraged if it takes a few test runs to dial in the settings.