Knitted Companion Cube (from Portal)




About: Hi, I'm a mother of four (and yes there is a set of twins in there) and grandmother to two. I enjoy making dollhouse miniatures. I think I like that hobby because it is a bit of everything, one day you are a...

The cake may have been a lie, but the cube is real. Do you miss your cube and can't wait for Portal 2? If so, then why not make your very own companion. And there's no need to throw this one in the incinerator.


An intermediate knowledge of knitting, you will need to be able to increase, decrease, cast on at the beginning of a row, pick up stitches and to knit intarsia or embroider over stitches to look like intarsia. A basic knowledge of how cubes are constructed is also useful.


Dark Grey –about 300g 12ply acrylic (I had to buy 2 x 200g balls, but I didn't use a lot from the second ball)

Light Grey – about 400g

Pink – small amount (I didn't actually have pink in 12 ply, so I used 2 strands of 8ply for the pink)

Stuffing material, I used a bit over 1kg of polyfill.

Finished Size

Using 12 ply yarn and 5mm needles, the finished cube is about 45cm across. You could use 8ply yarn and smaller needles (3mm maybe) and the result will be smaller and will probably use less yarn, but I haven’t had a chance to see the results yet.
At the time of writing this, I have a smaller cube close to being finished. Using 8 ply yarn and 3.25mm needles, the cube looks like it will be about 25cm across and has used 1 x 100g ball of dark grey.

Abbreviations etc.

St st – Stocking stitch

k1 –knit 1

sl 1 – slip 1 stitch

psso – pass slipped stitch over

k2tog – knit 2 together

p2tog – purl 2 together

All instructions to increase and decrease mean increase or decrease 1 stitch in either first stitch (beginning of row) or last stitch (end of row)

All pieces are worked in stocking stitch throughout.

Numbers in brackets at the end of instructions refer to the number of stitches you should have after finishing that row.

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Step 1: Sides

Sides (make 6)

*worked in st st throughout

Using 5mm needles and dark grey yarn, cast on 16 stitches.

Work 7 rows  st st beginning with a knit row

Next 2 rows: Increase both ends (20)

Next 2 rows: Cast on 2 stitches at beginning of row and increase at end. (26)

Row 12: Increase at end of row (27)

Row 13: Increase at both ends of row (29)

Row 14: Increase at beginning of row (30)

Row 15: Increase at both ends (32)

Next 4 rows: Increase at end (36)

Row 20: Purl

Next 2 rows: Increase at beginning of row (38)

Cast on 5 stitches at the beginning of the next 2 rows (48)

Work 20 rows

Cast off 5 stitches at the beginning of the next 2 rows (38)

Row 47: Decrease at both ends (36)

Row 48: Purl

Repeat rows 47 and 48 two more times (32)

Decrease at both ends of next 2 rows (28)

Row 55: Knit

Row 56: Cast of 2 stitches at beginning of row and decrease at end (25)

Next 2 rows: Decrease both ends (21)

Row 59: Cast of 2 stitches at beginning of row and decrease at end (18)

Row 60: Decrease both ends (16)

Work 6 rows

Cast off all stitches.

Using pink yarn, embroider a chain from top to bottom between the middle two stitches.

Mark the centre line across from one side to the other and embroider a chain across this line.

Step 2: Heart Circle

Heart Circle (make 6)

Using light grey yarn and 5mm needles, cast on 4 stitches

Row 1: Purl

Next 2 rows: Continuing in st st, cast on 2 stitches at beginning of row and increase at end (10)

Increase at both ends of next 3 rows (16)

Increase at end of next 3 rows (19)

Row 10:  Begin placement of heart. Knit 9 grey, 2 pink, then continue in grey, increasing at end of row (20)

Continue following graph for heart appliqué while continuing with the following shaping.

Row 11: purl

Row 12: increase both ends (22)

Work 6 rows st st

Row 19: decrease both ends (20)

Row 20: knit

Row 21: purl

Row 22: Decrease both ends (18)

Row 23: purl

Repeat rows 22 and 23 two more times (14)

Row 28: Decrease both ends (12)

Next 2 rows: Cast off 2 stitches at beginning and decrease at end (6)

Cast off.

Step 3: Edge Pieces

Edge pieces (make 12)

Using light grey yarn and 5mm needles, cast on 12 stitches

Beginning with a knit row, work 10 rows st st

Next 2 rows: decrease at both ends (8)

Next 2 rows: Increase at both ends (12)

Work 10 rows st st.

Cast off.

With right sides together, fold in half so cast on edge meets cast off edge. Stitch the v shaped tuck (one or two stitches will be enough) so that the piece sits naturally at an angle.

Step 4: Making Up and Corners

Making up and corners

Sew side pieces together as in diagram, then using corner instructions pick up stitches for corners between tabs A&B, E&F, C7D and G&H (along the yellow lines in the diagram)


With right side facing and using light grey yarn and 5mm needles, pick up 96 stitches evenly between tabs (32 stitches on each side piece)

Row 1: purl

Row 2: *(increase in first stitch, knit 30, increase in next stitch) repeat from * twice (102)

Next and every alternate row: purl

Row 4: k1, sl 1, k1, psso, k 29, k2tog, sl 1, k1, psso, k30, k2tog, sl 1, k1, psso, k29, k2tog, k1 (96)

Row 6: k1, sl 1, k1, psso, k 27, k2tog, sl 1, k1, psso, k28, k2tog, sl 1, k1, psso, k27, k2tog, k1 (90)

Row 8: k1, sl 1, k1, psso, k 25, k2tog, sl 1, k1, psso, k26, k2tog, sl 1, k1, psso, k25, k2tog, k1 (84)

Continue in this manner till the last row worked is k1, sl 1, k1, psso, k 1, k2tog, sl 1, k1, psso, k2, k2tog, sl 1, k1, psso, k1, k2tog, k1 (12)

Next row: P2tog til end (6)

Break off yarn (leaving a long enough piece to sew the corner piece together) and thread the end through the stitches remaining on the needle. Pull tightly to gather stitches and fasten off. Use remaining thread to sew row ends of corner piece together.

**Note, when knitting the 7th corner, just fasten off. Do not sew row ends together until after the 8th corner has been knitted.

Step 5: Continue Making Up

Continue making up

When the first four corners are knitted and sewn up, edges A&B will be at a right angle to each other, as will edges C&D, E&F and G&H. Sew these edges together – A to B, C to D, E to F and G to H.

When this is done, you can then pick up and work the corners between edge Q&R and U&V.

When these two corners are complete, sew edge Q to R and U to V.

You should now have an almost complete cube. Pick up and work a corner between the remaining two edges, but only fasten off when finished DO NOT sew edges of corner together.

Work final corner and sew up.

At this point, I found it easier to almost completely stuff the pillow then sew up the last corner (you should still have edges S & T not sewn up. Use this hole to add the last stuffing – You may need to push handfuls into the corners. When full, sew the last two edges together.

Adding details

Pin a circle heart piece to the centre of each side and stitch in place, leaving a small gap. Add a small amount of stuffing and close gap.

Pin edge pieces to the side edges and sew in place, again leaving a small gap to add some stuffing. Close gap and finish off.

Hug squeeze and enjoy the companionship of your cube as you like.. but don’t throw it in the incinerator!! challenge

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    15 Discussions


    8 years ago on Introduction

    This is honestly the coolest thing I have ever seen. You may be the best knitter in the entire world. I LOVE IT!!!!!!!!!

    1 reply

    3 years ago

    Oh wow, That came out Great! Love portal!


    7 years ago on Introduction

    I am a fan of Portal! When I saw this I was just shocked. Thank you so much!


    7 years ago on Introduction

    How did you do the heart in the middle? I'm an amateur and I don't have much experience with patterns like that. I know slip stitch, but that's about it.

    1 reply

    Reply 7 years ago on Introduction

    The heart is done using intarsia. Basically, you have bobbins with the different coloured yarn on them. You knit using the graph and when you get to the beginning of the heart, you join in the pink but don't break off the grey. Then you would have another bobbin of grey yarn, so each section of colour is worked from a separate bobbin or ball of yarn.
    There is a simple intarsia instructable here


    Reply 8 years ago on Introduction

    I don't crochet, so I really couldn't say. I've seen things that were crocheted in different shapes, so I guess it's possible. Maybe someone who does crochet might be able to help.


    hi there, check this site for a crochet version, its slightly different but still looks ace :) enjoy


    8 years ago on Introduction

    Awww, so plush looking! And you'll never have toeuthanize it :D


    Reply 8 years ago on Introduction

    Thank you.
    mmm, a voice chip. Now why didn't I think of that in the two weeks I was madly knitting lol. My daughter likes it anyway.. it makes her happy!