This cylinder study grows from a magic ring through six, twelve and eighteen stitches, then works six additional even rounds at eighteen. There are nine worked rounds and 144 single-crochet outputs. The base is closed by the initial ring, while the final eighteen-stitch rim remains open. This distinguishes a usable open component from a sphere with its last reductions accidentally omitted or a tube that is open at both ends.
Separate base width from wall height
Growth rounds determine the eighteen-position circumference at the wall. Even rounds extend that wall without adding increase sectors. In the saved example, the widest growth round plus six even rounds give seven consecutive rounds at eighteen. Adding another wall round would add eighteen outputs while keeping the rim count unchanged. Increasing the number of growth rounds would instead change the base and every following wall round, requiring a newly generated budget.
Plan an attachment only after measuring the rim
Fasten off and weave the tail on the inside, preserving the opening. The project supplies no cap, lining or receiving-part seam. If the cylinder will become a sleeve, limb or container insert, compare the actual rim length and insertion count with that other component before sewing. A measured circumference in centimeters does not by itself establish one-to-one loop compatibility. Keep a second project for any added cap rather than claiming this file includes its stitches.
Questions and troubleshooting
Why does my tube close at the top?
Check that the cylinder study is selected and that no sphere decrease sequence has been added after the sixth even round.
Does eighteen stitches guarantee a straight wall?
It establishes a constant count. Physical drape and taper can still change with tension, yarn and stuffing.
Should I turn at the marker?
No. Continue in a spiral, moving the marker. Turning would introduce another construction and surface relationship.
Can this pattern be used as a pot holder?
The counted form is a component study. Its size, material and suitability for any functional object need separate testing rather than being inferred from the cylinder name.
Exact setup, stitch key and complete sequence
Open the Amigurumi Shape Planner, choose cylinder, set growth rounds to 3 and even rounds or shaft length to 6. Download the exact original project JSON before editing it. Use smooth compatible yarn, a hook giving firm fabric, removable markers, suitable filling and a tapestry needle. The swatches identify component yarn roles; they do not assign a different yarn to every round unless a row explicitly says so.
In US terms, sc means single crochet, an increase works two sc in one old base and sc2tog consumes two bases to make one stitch. In UK mode those become dc and dc2tog without changing source coordinates or counts. Mark the first stitch of each separate spiral and move the marker after every completed circuit; do not add joining slip stitches or turning chains. Follow each part's own start, final rim and closure. Make the stated number of copies, then execute any separate attachment rows. Read the amigurumi shaping guide and compare the actual fabric after filling. The diagram is a counted construction reference; physical size, bend angle and finished suitability need a real sample. Finish every tail securely before handling the completed form.
Every worked round and attachment step
Open cylinder (make 1), round 1, base yarn #678591: Magic ring: ch 1 (not counted), 6 sc. Tighten ring and mark first stitch. Continue in a spiral without joining or turning. [6 outputs per copy]
Open cylinder (make 1), round 2, base yarn #678591: Repeat [0 sc, 2 sc in next stitch] 6 times. Each increase makes two stitches in one old base. [12 outputs per copy]
Open cylinder (make 1), round 3, base yarn #678591: Repeat [1 sc, 2 sc in next stitch] 6 times. Each increase makes two stitches in one old base. [18 outputs per copy]
Open cylinder (make 1), round 4, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. [18 outputs per copy]
Open cylinder (make 1), round 5, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. [18 outputs per copy]
Open cylinder (make 1), round 6, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. [18 outputs per copy]
Open cylinder (make 1), round 7, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. [18 outputs per copy]
Open cylinder (make 1), round 8, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. [18 outputs per copy]
Open cylinder (make 1), round 9, base yarn #678591: Sc once in each old stitch; move the first-stitch marker. Fasten off and weave the tail on the inside. Leave the final rim open; no cap or decrease round is supplied. [18 outputs per copy]
