When a needle takes new yarn while keeping its old loop, which stitch forms?
A Tuck stitch
B Knit stitch
C Miss stitch
D Pillar stitch
Answer: A. Tuck stitch. The tuck loop and old loop stay on the needle until a later knitting action casts them off together.
Contrast a miss stitch with a tuck stitch. What happens to new yarn at the missing needle?
A It forms a tuck loop
B It enters the hook
C It splits the old loop
D It passes as a float
Answer: D. It passes as a float. The needle does not take new yarn, leaving a float behind that position.
During clearing on a latch needle, where does the old loop move?
A Below the open latch
B Above the needle head
C Onto the yarn feeder
D Into the hook tip
Answer: A. Below the open latch. Clearing moves the old loop down the stem below the open latch.
As the latch needle descends, what closes its latch during normal knitting?
A The feeder tip
B The cam track
C The old loop
D The yarn package
Answer: C. The old loop. The old loop rises relative to the descending needle and pushes the latch shut.
After the latch closes, the old loop passes over the needle head. Name the action.
A Yarn feeding
B Guide-bar shogging
C Clearing
D Knock-over
Answer: D. Knock-over. Knock-over casts the old loop over the closed hook while the new yarn stays inside it.
Which mechanism closes the flexible hook of a bearded needle?
A Yarn feeder
B Presser
C Warp beam
D Guide bar
Answer: B. Presser. A presser bends the beard into its groove to close the hook.
On a compound needle, which part controls the hook opening?
A Hinged latch spoon
B Flexible beard
C Sliding closing element
D Warp yarn guide
Answer: C. Sliding closing element. A separate sliding element opens and closes the hook.
For open lace and technical net structures, which warp knitting machine family is commonly used?
A Circular single jersey
B Raschel
C Flat V-bed
D Circular interlock
Answer: B. Raschel. Raschel machines can work with guide-bar arrangements suited to open net and lace structures.
Identify the cam that pulls a needle down to draw a stitch.
A Stitch cam
B Guard cam
C Transfer cam
D Raising cam
Answer: A. Stitch cam. The stitch cam controls the drawing depth as the needle pulls yarn into the new loop.
When the stitch cam draws the needle farther down, how does the loop length normally change?
A It increases
B It becomes zero
C It stays fixed
D It decreases
Answer: A. It increases. With yarn supply able to accommodate the draw, a deeper draw uses more yarn per stitch.
For fixed yarn tex, which loop length gives the highest tightness factor?
A 3.6 mm
B 2.8 mm
C 2.4 mm
D 3.2 mm
Answer: C. 2.4 mm. Tightness factor is inversely proportional to loop length at constant yarn tex.
Loop shape factor is calculated using which ratio?
A Course density × wale density
B Loop length ÷ yarn tex
C Wales per inch ÷ tex
D Course density ÷ wale density
Answer: D. Course density ÷ wale density. The conventional loop shape factor is the ratio of course density to wale density, with both densities in matching units.
Suppose 84 cm of yarn makes 280 stitches. Find the mean loop length.
A 4.2 mm
B 2.4 mm
C 0.3 mm
D 3.0 mm
Answer: D. 3.0 mm. Divide 840 mm by 280 stitches to obtain 3.0 mm per stitch.
Two fabrics have the same loop length. Which yarn gives higher tightness factor?
A 12 tex
B 9 tex
C 25 tex
D 16 tex
Answer: C. 25 tex. At fixed loop length, tightness factor rises with the square root of yarn tex.
At 24 rpm, 36 active single-jersey feeds each knit one course per revolution. Find the course rate.
A 60 courses/min
B 864 courses/min
C 1,200 courses/min
D 720 courses/min
Answer: B. 864 courses/min. Every revolution forms 36 courses, so the rate is 24 × 36.
If fabric forms at 600 courses/min and has 20 courses/cm at the take-down, what is the length rate?
A 120 cm/min
B 12 cm/min
C 30 cm/min
D 60 cm/min
Answer: C. 30 cm/min. Dividing courses per minute by courses per centimeter gives the fabric length per minute.
Describe shogging in a warp knitting machine.
A Vertical needle rise
B Needle hook closing
C Lateral guide-bar motion
D Fabric roll winding
Answer: C. Lateral guide-bar motion. Shogging shifts the guide bar sideways along the needle row.
During a warp knitting overlap, what does the guide place yarn around?
A A sinker butt
B A take-down roll
C Its warp beam
D A needle hook
Answer: D. A needle hook. The overlap places yarn around the needle so it can be drawn into a loop.
With no underlap and an overlap at the same needle in successive courses, which structure forms?
A Satin weave
B Pillar stitch
C Twill rib
D Interlock jersey
Answer: B. Pillar stitch. A pillar stitch repeatedly knits on the same needle and does not connect neighboring wales on its own.
To secure an inlay, which structure holds the laid-in yarn in place?
A Needle hook only
B Knitted ground
C Loose warp beam
D Woven selvage
Answer: B. Knitted ground. The ground loops bind the laid-in yarn even though the inlay itself does not form knitted loops.
When narrowing a knitted panel by loop transfer, where are edge loops moved?
A Beyond the active edge
B Onto the feeder
C Toward the panel center
D Onto the take-down roll
Answer: C. Toward the panel center. Moving edge loops inward reduces the number of active needles and narrows the fabric.
Identify the flat knitting bed arrangement that gives the V-bed machine its name.
A One circular needle bed
B Two angled needle beds
C One vertical guide bar
D Two horizontal warp beams
Answer: B. Two angled needle beds. The two needle beds are inclined toward each other, forming an inverted V in cross section.
Interlock requires what relative alignment of cylinder and dial needles?
A One bed only
B Alternating gaps only
C All needles removed
D Opposed needles
Answer: D. Opposed needles. Interlock needles are arranged opposite one another. Opposing needles must be selected at different times to avoid collision.
Just after knitting, which change can occur when the fabric is freed from machine tension?
A Loop shape redistributes
B Needle gauge decreases
C Yarn tex always doubles
D All courses disappear
Answer: A. Loop shape redistributes. Released loops can change shape and dimensions as the fabric relaxes.
Gauge is 20 needles/in. Estimate the nominal needle pitch.
A 1.27 mm
B 5.08 mm
C 0.50 mm
D 2.00 mm
Answer: A. 1.27 mm. Pitch is the needle spacing. Divide 25.4 mm by 20 to obtain 1.27 mm.