Made and counted by Wren —

Blanket yarn modification guide for the Mathilda sea turtle

7.0mm hook, super bulky blanket yarn: modify Mathilda Sea Turtle shell plates for a flat, plush 17-inch turtle.

IntermediateLevel

4-6 hoursTime

6.5 mmHook

Super BulkyYarn

Jump to the pattern

About this pattern

This guide converts the Mathilda Sea Turtle from chenille to super bulky (category 6) blanket yarn. Shell plates A, C, D, and E start with a magic ring, skip round 2, and jump to round 3 of the original pattern to avoid a pointed shape. Hook A ranges 6.5mm to 7.0mm, Hook B 7.0mm to 8.0mm, chosen by tension. Finished size is approximately 17 by 9 inches.

This guide adapts the Mathilda Sea Turtle amigurumi pattern for super bulky blanket yarn instead of the chenille the original calls for. Shell plates A, C, D, and E are rebuilt from a magic ring, with round 2 skipped and round 3 picked up early to remove the pointed peak blanket yarn's extra height creates. Hook A runs 6.5mm to 7.0mm and Hook B runs 7.0mm to 8.0mm, sized to natural tension. Finished turtles measure approximately 17 inches long and 9 inches wide.

Chenille yarn compresses easily and adjusts readily to shaping, creating smooth, rounded curves, while blanket yarn is stiffer and holds its shape more rigidly once stuffed, often producing sharper angles instead of soft curves. Magic rings with fewer than 8 stitches compress flat in chenille but tend to cone into a protruding point in blanket yarn, which is why the shell plate and head starting rounds are rebuilt in this guide.

The pattern

Written out round by round

Materials

You’ll need super bulky blanket yarn (category 6, approximately 300g per 200m):

Main color

150-200 grams

Contrasting color

100-150 grams

Your natural tension plays a crucial role in determining the right hook size:

For loose tension crocheters

Hook A: 6.5 mm
Hook B: 7.0 mm

For tight tension crocheters

Hook A: 7.0 mm
Hook B: 8.0 mm

Abbreviations

ch = chain
st = stitch
sl st = slip stitch
sc = single crochet
hdc = half double crochet
dc = double crochet
inc = increase
dec = decrease
mr = magic ring
fo = finish off

Plates A, C, and D Modification

Using Hook A with tight or regular tension and your contrasting color:

Round 1Work 10 single crochet stitches in a magic ring (10 stitches total) After completing Round 1, skip Round 2 entirely and jump directly to Round 3 from the original pattern. This adjustment prevents the excess height that creates pointy plates.

Plate E Modification

These larger plates need slightly different handling:

Round 1Work 12 single crochet stitches in a magic ring (12 stitches total) Again, skip Round 2 and continue to Round 3 from the original pattern.

For Right-Handed Crocheters

Begin with your main color and Hook A, maintaining tight or regular tension:

Round 1Work 7 single crochet stitches in a magic ring (7 stitches total)(7)

Round 2Work 3 increases, followed by 4 single crochet stitches (10 stitches total) Then continue to Round 3 from the original pattern.

For Left-Handed Crocheters

Using the same materials and tension:

Round 1Work 7 single crochet stitches in a magic ring (7 stitches total)(7)

Round 2Work 4 single crochet stitches, followed by 3 increases (10 stitches total) Continue to Round 3 from the original pattern.

These adjustments prevent the pointed nose effect and create a more rounded, natural turtle head shape.

Tester's notes

These modifications apply only to the first two rounds of the specified pieces.

After completing the modified rounds, return to the original pattern to finish each component.

These adjustments work well for other super bulky yarns or if you naturally crochet with looser tension and prefer larger hooks.

Maintain consistent tension throughout your work for the best results.

Creating magic rings with 10-12 stitches in blanket yarn requires patience: make the ring slightly loose initially, then tighten and adjust after completing the first 2-3 rounds when you have more structure to work with.

tight magic rings containing 10-12 stitches, try using cotton or DK weight yarn for the base ring; once round 1 is complete, tighten it and secure it with a knot for a snug, secure finish.

Work in progress

Blanket yarn modification guide for the Mathilda sea turtle — photo 2

Blanket yarn modification guide for the Mathilda sea turtle — photo 3

Blanket yarn modification guide for the Mathilda sea turtle — photo 4

At a glance

Rounds	6
Parts	4
Level	Intermediate
Time	4-6 hours
Hook	6.5 mm
Yarn	Super Bulky

Gauge check

After round 1 of any shell plate, check that the magic ring circle lies flat rather than cupping upward; a flat disc confirms the hook and tension pairing suits the yarn's bulk.

If the circle domes under Hook A, move up to Hook B and recount stitches to confirm the round 1 total (10 for Plates A, C, and D; 12 for Plate E) before continuing to round 3.

Stitch-count checkpoints

For Right-Handed Crocheters · Round 1: 7 sts
For Left-Handed Crocheters · Round 1: 7 sts

If something looks wrong

The shell plate comes out pointed instead of rounded.: Round 2 was worked instead of skipped. On Plates A, C, D, and E, round 1 should jump straight to round 3 of the original pattern; rip back to the round 1 stitch count (10, or 12 for Plate E) and skip round 2 again.
The finished turtle is noticeably: Hook size doesn't match natural tension. Hook A covers 6.5mm-7.0mm and Hook B covers 7.0mm-8.0mm; swap to the paired hook and rework the piece.
The plate feels stiff instead of soft and relaxed.: The hook is sized too close to a chenille hook. Blanket yarn needs a hook 2 to 3 sizes larger to keep the fabric from tightening; move up within the given Hook A/Hook B range.
The stitch count is off going into round 3.: Plates A, C, and D should total 10 stitches after round 1; Plate E should total 12. Count stitches before continuing, since skipping round 2 leaves no later round to catch the error.

Yarn substitutions

Category 6 super bulky cotton-blend	Produces a firmer plate with less give than acrylic blanket yarn. Hold Hook A at the lower end (6.5mm) to keep the fabric from stiffening further.
Category 5 bulky polyester	Gives a smaller finished turtle than the 17 by 9 inch target, since it's a step down from category 6. Drop to a smaller hook than the 6.5mm-8.0mm range given here and expect to use less than the 150-200 gram amount.
Category 6 chenille (the original fiber)	Returns to the original pattern's rounds with no skip needed. Use a hook roughly 2 to 3 sizes smaller than the 6.5mm-8.0mm range given for blanket yarn.

Original pattern: https://amigurumicorner.com/mastering-the-mathilda-sea-turtle-blanket-yarn-modification-guide/

FAQs

Questions

Why skip round 2 on these shell plates?

Round 2 adds height that, combined with blanket yarn's bulk, creates a pointed peak instead of a rounded plate. Skipping from round 1 straight to round 3 of the original pattern removes that extra height on Plates A, C, D, and E.

How is Hook A different from Hook B?

Hook A covers tight to regular tension at 6.5mm-7.0mm; Hook B covers looser tension at 7.0mm-8.0mm. Pick based on how yarn naturally sits in the hand, not on which plate is being worked.

Does this modification apply to every part of the turtle?

No. It's limited to the first two rounds of Plates A, C, D, and E, plus the right-handed and left-handed opening rounds; every other round follows the original pattern as written.