Wednesday, October 29, 2025

Four Needle Double Knitting in the THIRD DIMENSION
Part 1: Horizontal Baffles

 Double knitting three dimensional tubes (baffles) like on puffer jackets.

Horizontal baffles
The preview to this series on four-needle double knitting promised fabrics with tubes which could be stuffed, like a puffer jacket. Technically called "baffles," these come in two flavors: vertical and horizontal. Today's post, part 1, is about horizontal baffles. Part 2 (next post) features vertical baffles. 

"Picking" and horizontal baffles
Four-needle double knitting has two different techniques: "slide-by" for blocks of color, and "picking" for speckles. Today's horizontal baffles use only the"picking" method. Picking pinches together the front and back fabrics of double knitting along a horizontal "lock row," and this is what makes the baffle. 

Different looks
There are two different kinds of picking, which make two different looking lock rows. 
--lock rows via "picking" in an alternating stitch pattern--this is the speckled appearance of the original kind, shown in the previous post and this video.
--lock rows via a continuous-line variant of picking called ping-ponging, introduced today. 

Here's what these different lock rows look like in real life.
Horizontal baffle swatch
close-up lower right: alternate stitch picking lock row--single 
close-up left: alternate stitch picking lock row--triple
close-up upper right: continuous-line "ping-pong" lock row in contrasting color 

The video below is an overview, showing more about lock rows.


If the video does not load for you, here is a direct link

Lock rows in four needle double knitting, via alternate stitch picking (version 1 of lock rows)

This green and white horizontal baffle sampler was started by casting on some white stitches and working 11 rows. Green stitches were then picked up right through the white stitches, and 11 green rows were knit--this is the default method for casting on double knitting.

(Not mentioned in the video is how the top ends: that is via purl grafting).

Up until row 11, the fabrics are only attached at the bottom, but on row 12 of each fabric, the four needles (two circulars) are held together and both fabrics are worked into one by "picking" across row 12 in an alternating-stitch pattern. A green knit on the front needles is followed by a green purl on the back needles, then a white knit on the front needles is followed by a white purl on the back needles, and so on. "Picking" colors alternately in four-needle double knitting made the horizontal "lock row"   shown here in close up (the lighter green stitches).

In a more macro view and from the reverse side, single alternating-stitch lock rows are shown by the black arrows in the photo below.

Above this lock row of double knitting, another 11 independent rows of each color were worked (meaning, 11 rows worked on one set of needles for the green fabric and 11 rows on the other set of needles for the white fabric) followed by another lock row and so on. With picking, the stitches stay on the individual needles for the independent layers AND for the locking row, per photo.

You can choose to have single color stripes with a contrast color locking row, such as the two green stripes separated by a white locking row, lower part of photo, or the layers can change color above the locking row, giving alternating color stripes like white above green, upper part of photo. Both versions lock equally well, it just depends on what look you're going for. 

Blue arrow  back layer.  Green arrow  front layer.
Brown arrows 
 baffles (tubes) formed when the layers are locked shut via double knitting the "lock row" along the long edge.
Black arrows
 lock rows: the stitches are worked on alternating needles, joining the layers into a single double-thick fabric for one row. The top black arrow (curved) shows a lock row in progress.

Combining individual layers with lock rows is a very fast kind of double knitting: makes a double thick fabric in double time. And, to fancy things up a bit, you can work designs into the stripes. This close up shows a name and date worked in ordinary stranded color-work in a darker green into a white stripe--on this swatch, I messed around with different-width letters and numbers. The corresponding stripe on reverse is plain. 

SAM-ple of stranded writing: "Sam" short for "Sample." 

As for picking lock rows, these need not be every-other-stitch. Alternating stitch lock rows can be any pattern which frequently crosses yarns from one fabric face to another. Here's the little checkerboard from above. These alternating picked stitches, three rows high, are also a "lock row."

Triple lock rows

This little WIP, a child's vest (back view) also features triple lock rows, some in pink, some in maroon. The alternating stitches within each triple lock row are arranged in more random, experimental patterns. 

The hearts in the second baffle from bottom were worked in stranded knitting,  just like the "SAM" and "2025" above. 


Continuous line lock rows via ping-ponging (version 2 of lock rows)

On the SAM swatch, the continuous line contrast color lock row looked like this in close-up.

Continuous-line lock row worked via "ping-ponging."

Here's the project from the opening photo. It has this same kind of lock row. Specifically, on this seat pad, the green and blue stripes are worked shut by a continuous third color: the rose color yarn. The vertical baffle up the side is worked by always keeping the edge stitches in their original color, (more about side edges below). 


Here is a close-up of the fabric, shown after being stuffed (more about stuffing below). 

In this side-view, the 3-D pop of the baffles really shows

The green and the blue fabrics are worked as independent fabrics for four rows each. Then on the fifth row, they are locked together with rose. This is done by picking EVERY stitch, front and back alternately, in the rose yarn.

In this WIP shot, a rose-colored lock row is being worked. The rose appears on both sides as an unbroken (continuous) line: a different look from speckled alternating-stitch lock rows.

The green and blue were used to work the 4 edge stitches (borders). Once past the edge stitches, the rose colored yarn took over. The green and blue yarns, not in use at this time, strand very loosely along in the ditch between front & back needles. They remain in the tube being sealed shut by the rose-colored lock row in progress, and won't emerge again until it's time to knit the border: the last 4 stitches.

Working the rose-colored lock row is simple: 

  • The green and blue yarns are called the "yarn(s) not in use." They are simply held in the ditch between the two needles. 
  • Then, the rose colored yarn, called the "yarn in use" is simply worked all the way down the entire row, alternating front and back needles, meaning: using only rose, a front stitch is knitted, followed by a back stitch purled, then another stitch knitted, another purled and so on. In this way, the rose is alternately "picked" front and back down the row.

Alternately picking the same yarn all the way down a row bounces the yarn in use (rose) back and forth between the front and back needles. As it bounces back and forth, it travels over the blue and green "yarns not in use,"just as a ball bounces back and forth over the net in ping-pong. That's why this style of picking is called "ping-ponging."

The yarn in use ping-pongs back and forth from one fabric face to the other, always passing over the "yarn not in use," like a ping-pong ball over a net. The yarn not in use, the green and the blue, are stranded in the "ditch" between the front and back needles.

Here is a close up of the ping-pong path of the rose colored yarn as it travels from needle to needle, sealing shut the two layers and fusing them into one double sided-fabric along the lock row. This  continuous rose-colored row, worked front and back, locks together the top of each green and blue stripe.

Path of the rose-colored yarn as it "ping-pongs" between front and back needles

Three things about the chair pad project


--Edge stitches. On this cushion, the edges were held in their original colors whether on a lock-row or otherwise. This makes an edge of continuous color as explained here. This means the rose colored lock-row doesn't go all the way across. Blue and green knit their 4 respective edge stitches, then they dive into the ditch and the rose starts. At the other end, the rose stops short. When 4 stitches remain to knit, the green and blue climb back out of the ditch and again knit their 4 edge stitches, front and back. In sum, the green and blue strand along "in the ditch" between the front and back fabrics along the rose-colored lock row, but dive to the surface for the 4 edge stitches, left and right, front and back.
 (In this project, I used 4 edge stitches: the minimum is 3, maximum, 5.)

--LOOSE in the ditch or cut? For a stretchy end result, keep the not-in-use yarns LOOSE in the ditch. Test for tightness: stretch while still on the needles. Stranding takes more yarn than you think. 

As for cutting: on one hand, it might seem a waste to strand all that yarn in the ditch. It might seem that cutting the strands would save yarn. On the other hand, for shorter rows, the length of the tails is going to approach the length of the strand, so, not a big yarn savings. Also, if there is any unraveling to do, uncut yarn is much easier to re-knit. And cutting makes more tails to work around. 

However, bottom line: there's no structural reason all that yarn has to be stranded in the ditch. If knitting with precious yarn, or with long rows, then cut if inclined. This means leaving tails a couple of inches long at both ends of the baffle, rather than running long strands in the ditch. 

--Contrast / no contrast. There's no reason a ping-ponged (continuous) lock row has to be a third contrast color. On the chair pad, the lock row could have been worked in green or blue leaving rose out entirely.

Couple more things about horizontal baffles in general

 --Good intro. Working horizontal baffles via lock rows would be a good first intro to four needle double knitting "picking." The first time trying, the tension is going to be pretty terrible, but it's all still going to work out OK. Re-watch the picking video from the last post, and re-read the note about adjusting tension after the fact. Even if your tension is comically loose as you work the locking row, the important thing is that the stitches have been interlocked to bring the fabrics together. By stopping every few inches to adjust the tension before knitting further, the finished product will come out fine. Each subsequent lock-row gets better, too. 

--Straight pin helper. Stockinette rolls. So, on the lock row, each layer wants to roll strongly away from the other. Use a straight pin to fasten the layers, then move the pin along as you work down the row--one less thing to fight against. 

Stuffing baffles 
--Wide baffles. The green and white "SAMple" has wide baffles, stuffed with a doubled-over loop of jumbo yarn per overview video. The even wider baffles of the baby vest WIP are stuffed the same way. The kind of yarn used on both is Bernat  big blanket yarn, a fluffy kind of chenille.

Geek note: "Big blanket" is for sale at this time, but for how much longer? Novelty yarns are often discontinued (remember pom-pom and ruffle?) If stuffed baffles might be in your future, maybe stash a few balls now. 

Another trick for wide baffles: use double sided fusible batting, cut in strips. This makes a fabric not at all stretchy: good for chair pads or potholders, but not clothing or blankets. (I made a baby blanket this way once, but it was not popular: too stiff. Oh well! I make mistakes so you don't have to.) With fusible batting, once the strips are threaded into the baffle, the item is steam-ironed through a pressing cloth to activate the fusing.

--Narrow baffles. The blue/green/rose chair pad features narrower baffles. These are stuffed with a double strand of bulky yarn. The process is the same: a loop of bulky yarn drawn through the baffle with a hook (a longer Afghan hook for the chair pad). 

Stuffing yarn: bulky, left, for smaller tubes & baffles, jumbo "big blanket" chenille for larger

When doubling yarn, pull through so both strands lay flat (next to one another, not twisted over one another). Un-twisted stuffing lays nicer: worth the trouble. 

Finishing side edges: preview.  
With four-needle double knitting, the edges are never connected to one another during the knitting process. In fact, the default edge is to leave the edges loose, where the powerful force of stockinette curl means they will curl together forever. However, for stuffed horizontal baffles, a loose edge won't work: the stuffing shows. 

...the stuffing shows

Therefore, the sample swatch and the chair pad, the edges were connected, but after the work was finished. 

preview
chain edge (left) --- zig zag edge (right)

Coming up: a whole post on side treatments, featuring these edges and more. Stay tuned! 

--Washing. Yarn-stuffed baffles are hand-wash. Even the gentlest machine spin can dislodge the stuffing. However,  if left unstuffed, baffled double knit fabric can be washed like any other hand knit. 

Final thought 
Horizontal baffles are actually a sub-set of independent layers combined with double knitting. More on that subject at this link. 

--TK

Questions? Feedback? Contact me at 
Blue Sky  @techknitter.bsky.social or  talk to me about this post on Ravelry TECHknitter forum


This is one in a series on Double Knitting. The series so far: