Working into the back bump of a starting chain leaves its two front loops visible along the bottom edge. That can give a scarf, strap or small flat project a more finished-looking foundation. The stitch itself stays the same; you are changing where the hook enters the chain.
Stitch terminology: This guide uses US names. US single crochet is UK double crochet; US half double is UK half treble; US double is UK treble. See the full US/UK reference.
Turn the chain over before inserting the hook
The front of a relaxed chain looks like a line of Vs. Turn it over and look for the small raised bars running along the back. Each bar belongs to one chain. Those bars are often called back bumps, back bars or the third loop of the chain.
Do not confuse them with the third loop of a half double crochet. The names describe different structures in different places. Here, you are still working in the starting chain.
Try a short single-crochet row
Chain thirteen. The loop on the hook is not one of those chains. Find the back bump of the second chain from the hook, insert under it and make a single crochet. Continue into one back bump of each remaining chain.
You should have twelve single crochets and an unworked pair of chain loops along the lower edge. Chain one, turn and work twelve ordinary single crochets through both top loops. The turning chain does not count for this sample.
Keep the chain loose enough to work into
A tight foundation makes the bumps difficult to lift. Rather than stabbing into the yarn, remake the chain with a more relaxed loop size. You can compare a chain made with a slightly larger hook, then return to the working hook for the first row.
That is an experiment, not a fixed rule that every foundation needs a larger hook. Check whether the finished starting edge actually matches the width of the rows above it.
Stop the chain twisting halfway through
Support the chain close to the next insertion point. If it rolls, pause and locate the next back bump instead of continuing through whichever loop happens to face you. Switching between bumps and front loops can give the foundation an uneven appearance.
For a long chain, add markers at regular intervals while counting. Move slowly for the first row; later rows are usually easier to read because the stitch tops are larger and more stable.
Decide whether the exposed edge is useful
The tidy lower Vs can help when seaming two edges together or adding a border. They also make a narrow bookmark or scarf look more consistent at its top and bottom. For a project whose foundation is completely enclosed, the visual difference may matter less.
If a pattern later works into the opposite side of the starting chain, inspect its instructions before changing the insertion method. It may expect particular free loops or a particular orientation around an oval.
Compare the result after finishing
Place two small samples side by side: one worked into the back bumps and one made using your usual chain insertion. Check edge width, ease of seaming and the appearance after washing according to the yarn label. Choose the method that improves the actual project, rather than assuming a neat-looking sample must suit every construction.
Continue learning
Review chain anatomy · Try a chainless foundation · Work around both sides of a chain
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