Sailrite Ultrafeed LS-1 Manual

ULTRAFEED®LS-1 & LSZ-1
GUIDEBOOK
SET-UP • USE • MAINTENANCE • TROUBLESHOOTING • SCHEMATICS

Table of Contents
Ultrafeed®Safety 1
Ultrafeed®Set-Up 2
Thread 2
Needles 3
Winding Bobbins 5
Threading the Machine 7
Removing & Installing Bobbin Case 9
Installing Bobbin in Bobbin Case 10
Picking Up Bobbin Thread 11
Using the Ultrafeed®12
Starting to Sew 12
Regulating Stitch Length 13
Sewing in Reverse 13
Turning Corners 13
Switching from Straight to Zigzag Stitch
(LSZ-1 Only) 14
Straight Stitch Needle Positioning
(LSZ-1 Only) 14
Thread Tension Adjustment 15
Adjusting Pressure Foot Tension 17
Removing Material from Under
the Presser Foot 17
Home Sewing 18
Welting & Cording Application 19
Ultrafeed®Maintenance 21
Lubrication 21
Marine Use & Potential for Rust 21
LS-1 Lubrication Points 22
LSZ-1 Lubrication Points 25
Troubleshooting the Ultrafeed®28
Thread Tension Doesn't Release 28
Inconsistent Stitch Tension 29
Clutch Will Not Disengage 30
Removing the Hook to Clean the Shuttle
Race Guide and Free Thread Jams 30
Skipped Stitches 31
Thread Issues 33
Needle Issues 37
Bobbin Winding Issues 38
Belt Issues 39
Ultrafeed®Timing 40
Hook/Driver Gap 48
Schematics 49
Specifications 63
Warranty 64
Welcome to Your
Ultrafeed®Sewing Machine!
You are now the proud owner of one of the toughest, most
versatile portable sewing machines around.
With the Ultrafeed, you can go from your home to the dock and sew up projects from
sails and boat covers to upholstery. This guidebook will give you an in-depth look
at your machine, all its power and features, as well as teach you proper use and
maintenance and give helpful troubleshooting advice.

Ultrafeed®Safety
Please observe the following when using your Sailrite sewing machine:
1. Do not operate if you or the machine are
wet or may become wet.
2. Operate the machine on a rm, level
surface with adequate room for safe
operation.
3. Observe caution when placing your hands,
other body parts, or clothing near any
moving parts including but not limited to
the walking foot, needle, balance wheel,
and belts.
4. Do not run the machine without its covers
in place.
5. Do not stop the movement of the balance
wheel with your hands.
6. Always use the proper voltage required for
the motor.
7. Do not drop the machine.
8. Wear protective eye wear when sewing.
9. Wear shoes when operating the foot
pedal.
10. Provide supervision when allowing
children or those unfamiliar with the
Ultrafeed®operations to use the machine.
11. Do not use the machine around ammable
materials.
12. Do not use a plug adapter or extension
cord that bypasses the ground pin.
13. When plugging the foot control wiring
into the machine, be cautious to connect
the receptacles correctly to avoid electric
shock.
WARNING: Some products may be fabricated from materials which may contain
chemicals known to the State of California to cause cancer, birth defects or other
reproductive harm.
THREAD
SIZE
G O V.
SIZE
TEXTILE
SIZE
TENSILE
STRENGTH
NEEDLE
SIZE
FABRIC WEIGHT
RECOMMENDED
Gen. Purpose N/A N/A N/A #10 or 12 < 6 oz.
V-30 AA 30 4.5 lb. #12 or 14 < 1.5 oz.
V-46 B45 7.1 lb. #14 or 16 < 3 oz.
V-69 E70 10.6 lb. #16 or 18 3–6 oz. & Sunbrella
V-92 F90 14.2 lb. #18 or 20 6–10 oz. & Sunbrella
Prolen N/A N/A 6.7 lb. #14 or 16 3–20 oz. & Sunbrella
Ultrafeed®Set-Up
Thread
Ultrafeed® sewing machines can handle any polyester, nylon, cotton, Prolen
or monolament thread from general purpose to heavy-duty V-92.
Recommended needle sizes are roughly one size
larger than those recommended for household machines.
This chart offers needle and thread size recommendations for sewing standard, woven fabrics. Needle and thread recommendations for sewing
speciality fabrics are available online in our Thread & Needle Recommendation Guide, downloadable from every fabric detail page.
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1

Needles
Ultrafeed®sewing machines require 135x17 needles sizes #12 to 22 or
135x16 leather needles, all available at Sailrite. A size #20 needle is used for
most medium to heavy sewing.
Needle Installation
Ultrafeed®needles are round on top, unlike
home sewing machine needles. As a result,
proper installation must be exercised carefully.
Improperly installed needles are the main
reason users call for help. Please be sure
that the needle eye is not twisted.
The needles have two distinct sides (1& 2).
One side has a long channel or groove (B)
(locate this groove with your ngernail if you
cannot see it), and the other side has a scarf
(D) i.e., a carved out area, just above the
needle eye (C).
When installed, the side with the needle eye
and groove should be facing outward i.e. to the
left as you face the machine.
CAUTION: If the needle is inserted the wrong
way, the machine will skip stitches and break
thread.
To make sure your needle is inserted far
enough, you can look through the sighting hole
(3, E) near the bottom of the needle bar. The
top of the needle should be fully visible in the
sighting hole and pushed all the way to the top.
ANeedle bar thread guide hole
BNeedle groove
CNeedle eye
D3/16 inch (5mm) ~ height of scarf
ESighting Hole
Ball Point
DI Leather
Round Point
SD1
Needle Types
Round point needles are used for most
standard sewing. Serv7 needles are modied
round point needles that have a humped
scarf for optimal loop formation and prevent
skipped stitches.
Ball point needles are specically designed
for use with knit or stretchy materials.
SD1 needles are optimized for sewing heavy,
dense assemblies.
DI needles are ideal for working with leather.
2
D
A
B
C
1 3
E
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Disengage the Clutch i.e.
Posi-Pin Clutch System:
To prepare your machine to wind bobbins,
rst disengage the Posi-Pin Clutch System, to
allow for bobbin winding without running the
machine (4).
Simply pull the pin out of the balance wheel
and place it in the center hole as shown to
store (5).
To continue sewing, re-engage the clutch:
1. Push the Posi-Pin gently into any of the
three Posi-Pin holes in the balance wheel.
2. Rotate the balance wheel while lightly
pushing on the Posi-Pin until you feel it
connect with any of the 4 bushing holes.
3. Push the pin all the way in and release.
Winding Bobbins
A partially wound V-92 bobbin is already
loaded in the machine. Skip this step if you
wish to test sew with the pre-loaded bobbin.
>Posi-Pin clutch
DISENGAGED
>Posi-Pin clutch
ENGAGED
Thread the Bobbin
On the machine:
1. Thread comes off top of cone to thread
stand arm (A).
2. Pass through thread post (B).
3. Wrap around bobbin tensioner (C).
4. Run under and up through a hole in top
of bobbin (D). Place bobbin on post and
push to the right. Hold onto thread tail
briey and power machine with the clutch
disengaged to wind bobbin. Stop after
several rotations and cut the thread tail off
ush with the bobbin side.
5. Continue winding until the bobbin is full.
Then remove the bobbin from the winder
post by pushing the post to the left and
pulling the bobbin off. Cut the thread.
A
B
C
D
It's faster to wind while you sew!
Run thread to the bobbin winder from an extra
cone of thread. Simply place the second cone
beside the primary cone and lead the thread up
through the same guides. Follow normal bobbin
winding instructions but do not disengage the
clutch.
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Threading the Machine
1. Thread comes off top of cone to thread
stand arm (A).
2. Pass the thread through one hole in the
thread post (most direct route to bobbin
tensioner) (B). For home sewing, use the
post to hold the thread spool.
3. Pass through pig tail of bobbin tensioner
(C).
4. Loop through ear holes (D).
5. Thread through upper tension (shown
without cover knob) (E). Make sure lift
lever (F) is raised up to release tension
plates so thread can pass through.
6. Pass through take-up arm (right to left)
(G) and then under end cover.
7. Pass through the needle bar thread guide
hole (H) and then down through the
needle eye from left to right (I).
A
B
C
D
E
F
G
H
I
6
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Installing Bobbin
in Bobbin Case
1. Insert a threaded bobbin (A) into the
bobbin case (B) with thread coming off the
left side in a clockwise rotation.
2. Hold the tail of the thread while pushing
the bobbin into the bobbin case.
3. Pull the thread through the slit (C) in the
edge of the bobbin case.
4. Continue pulling the thread under the
tension plate (D).
5. Snap thread into position under tension
plate and pull out about a 6 inch tail of
thread.
ABobbin
BBobbin Case
CSlit
DTension Plate
ESpring-loaded Lever
FFinger
GRetaining Ring
Removing & Installing
the Bobbin Case
The bobbin case (B) is located
on the underside of the machine
beneath the presser foot (7).
Removing — Lift the spring loaded lever (E)
and pull the bobbin case out. With the lever
held open the bobbin is captive in the bobbin
case. Release the lever and the bobbin will
fall out.
Installing — Pull and hold the spring-loaded
lever outward (to keep the bobbin from falling
out) and push the case onto the axle of the
gib hook. The nger of the bobbin case (F)
should point upward.
If the lever (E) is held up until the bobbin
case is completely installed, the lever, when
released, will lock onto the axle and there will
be no clicking sound. If the lever is released
before the bobbin case is pushed completely
in place, there is a clicking sound when the
case is pushed all the way on. The nger of
the bobbin case will drop into the notch in the
hook’s retaining ring (G).
B
F
7
E
G
A
8
B
C
D
E
F
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Using the Ultrafeed®
Ultrafeed®Sewing Machines arrive tuned and optimized for sewing heavy
materials like sailcloth and marine canvas. If you want to sew lighter, home
fabrics you will need to make adjustments to the machine, which are outlined
in the Home Sewing section (p. 18).
Starting to Sew
1. Plug the machine into an outlet.
2. Use the lift lever (13) to raise and lower the
presser foot onto the material.
3. The thread from the needle and the bobbin
should be behind the foot as you start to
sew. Hold them down with your nger.
4. To mark your starting position, you may
want to rotate the balance wheel towards
you until the needle is buried in the fabric.
5. Press the foot control pedal to begin
sewing and release the trapped threads
after the rst few stitches. If the thread
ends are not held down for the rst few
stitches, a rats nest at the beginning of
sewing may occur.
Picking Up Bobbin Thread
After the machine is threaded and the bobbin case (with bobbin) is installed,
pick up the bobbin thread as follows:
1. Hold the needle thread loosely to the side
(9) and rotate the balance wheel toward
you until the needle moves down and then
back up.
2. As the needle nears its highest point,
pull the needle thread gently. The bobbin
thread should come up through the needle
hole, with the needle thread, in the form of
a loop (10).
3. Pass a screwdriver under the presser
foot from right to left to pull the thread out
away from the machine (11).
NOTE: If the bobbin thread does not
appear when the needle is lowered and
raised, check to make sure 5 to 6 inches
of bobbin thread is hanging loosely from
the bobbin case and repeat steps 1-3
again.
4. Completed set-up should look similar to
(12). Now you’re ready to sew!
ARaise
BLower
CPressure Regulating Thumb Screw
DO NOT operate the machine when threaded without material under the presser foot (and foot
lowered). The machine will most likely “lock up” and be inoperable until the thread jam is cleared.
910 11 12
13
A B
C
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Switching from
Straight to Zigzag Stitch 
The stitch width adjustment lever controls
the stitch type as well as the width of your
zigzag stitch (15). When the lever is on “0” the
machine is in straight stitch. Moving the lever
to “1” produces a 1mm zigzag stitch and so
on through “5”.
DO NOT change the position of the stitch
width lever when the needle is in the fabric or
the needle may bend.
Straight Stitch
Needle Positioning 
In straight stitch mode (stitch width
adjustment lever at “0”), the needle can be
moved left, right, or center (16). This is very
helpful when installing zippers where it is best
to have the needle as close to the zipper teeth
as possible. Gently push down on the lever
before moving it left, right or center. It may
also be helpful to move the balance wheel a
little while moving the lever.
DO NOT change the needle positioning when
the needle is in the fabric or the needle may
bend.
Sewing in Reverse
Position the needle fully up or fully down and
push the stitch length lever all the way down.
Hold the lever down until the reverse sewing
is completed. The lever is spring loaded and
will return to its forward position when you
release it. When the machine is operating at
1/4-speed or faster, reverse can be engaged
on the y.
DO NOT rotate the balance wheel in the
wrong direction. Always turn it towards you
(from the top) to avoid thread jams in the
lower mechanism.
Turning Corners
First turn the balance wheel toward you until
the needle is at its lowest point. Then lift the
presser foot, turn the material to the new
direction (the needle acts as an axis), drop
the foot and start sewing in the new direction.
DO NOT attempt to change sewing directions
when the machine is at rest with the needle
positioned mid-stroke. This will cause a
skipped stitch or needle deection.
Rotating the fabric while the machine is at
rest with the presser foot down may bend the
needle.
Applies to LSZ-1 Model Only
Forward Feed
Reverse Feed
0 mm
Regulating Stitch Length
The EZ Set Stitch Length Plate (14) sets both
forward and reverse stitch length. To set the
stitch length, loosen the two thumb screws
(A), slide the posts up or down and tighten
the screws. The thumb screw stops (B)
restrict the movement of the Feed Regulator
Lever (C), which is spring loaded to always
rest against the upper stop.
B
C
A
15
16
+6 mm
Longest
Forward
+6 mm
Longest
Reverse
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Thread Tension
Adjustment
Tension adjustment refers to the
combination of tension on both the
upper thread and the bobbin thread.
The correct combination of thread tension (17)
results in a stitch that looks identical on both
sides of the material (i.e., the knots of the
stitches are pulled into the fabric and are no
more visible on the top than on the bottom).
The primary problem when using a heavy
thread is incorrect upper thread tension.
When stitch tension is a problem, it is usually
a consequence of too much or too little
tension on the upper thread.
Tension changes to the bobbin thread should
only be made when upper tension changes
alone do not solve stitch tension. In general,
bobbin tension requires just about a two
ounce drag on the thread (similar to what you
feel when pulling dental oss off a spool).
The Ultrafeed®has a thread
tensioning knob on the front that the
upper thread runs through (18).
The upper tension knob can be turned up
to ve revolutions to compress a spring that
squeezes two disks together.
When the presser foot is lifted the upper
tension disks are pushed apart. This releases
the top thread tension so fabric can be
removed from under the machine foot without
ghting thread tension.
DO NOT lift the presser foot when the upper
tension knob is less than a 1/2 turn from
maximum (turned snugly clockwise).
If upper tension is tightened all the way down,
raising the presser foot may bend the lever
inside the machine that separates the disks,
preventing the disks from opening correctly.
Knots pulled to top:
1. Decrease upper tension
2. Increase bobbin case tension
Knots visible on bottom:
1. Increase upper tension
2. Decrease bobbin case tension
Knots centered — PERFECT STITCH
17
18
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Removing Material from
Under the Presser Foot
1. Stop the machine with the needle at its
upward most position (21).
2. Raise the lift lever.
3. Pull the material straight back to remove it
from under the foot (22). It may be helpful
to rock the balance wheel forward and
back to free the thread from the tension
assembly.
4. Cut the two threads to free the material,
leaving at least a three inch length of
thread coming out of the machine.
Use this simple checklist before sewing light to moderate weight fabrics:
1. Use an appropriate thread.
Home sewing machine thread should be
used in clothing or general home sewing.
Nylon thread is often preferred for interior
upholstery.
2. Select an appropriately sized needle.
Match the fabric and thread weight to the
needle size (p. 2).
3. Decrease pressure on the foot.
Too much pressure, if sewing lighter
fabrics, can scuff the material.
Adjust the foot pressure by loosening the
pressure regulating thumb screw (p. 12,
13). If it comes out, just screw it back in
a few turns. See "Adjusting Presser Foot
Tension" (p. 17).
Decrease the upper thread tension
and, if necessary, increase the bobbin
tension (p. 15, 17).
Too much upper thread tension will cause
the fabric to pucker. When using light
weight thread it may also be necessary to
increase the bobbin tension if the spring is
not clamping down like it does on heavier
thread.
4. Check for clockwise
rotation of the thread spool.
When placing home sewing machine
spools on the thread post, be sure the
thread spool is turning in a clockwise
manner to ensure the post it rides on is
tightened, not loosened.
Home Sewing
The Ultrafeed®is a great sewing machine for those who enjoy crafting;
quilting; home, auto & RV upholstery; and general sewing.
Several of the same characteristics that make this machine great for sail and canvas work also
make the machine suitable for upholstery fabrics and most home fabrics. However, as a heavy-
duty machine, the Ultrafeed®is not ideal for sewing very light and delicate fabrics like silk, light
sheers or chiffon.
21 2219 20
Adjusting Presser Foot Tension
The amount of downward pressure put on the
fabric by the presser foot is controlled by the
Pressure Regulating Thumb Screw (A). This
screw compresses a long coil spring above
the presser foot. Turn the screw clockwise to
increase the downward foot pressure. Turn
the screw counterclockwise to decrease the
foot pressure.
1. For sewing heavy, hard-to-feed materials,
it is best to have very high pressure on
the foot for optimum feeding. For these
materials, tighten the screw until only 1/2" of
the screw’s threads are showing (19). When
sewing delicate or spongy materials, reduce
the foot pressure. Turn the thumb screw
until it comes free of the machine and then
rethread it about 3 complete rotations for the
lightest spring setting (20).
A
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> LS-1 welting tunnel in
presser foot (back view)
> LSZ-1 welting tunnel in
presser foot (back view)
Welting & Cording Application
The standard presser foot on Ultrafeed®sewing machines includes a 1/4"
welting tunnel that makes installing 5/32" foam piping quick, easy, and more
accurate.
If looking from the back at the upper presser foot, there is a groove (tunnel) under the foot just to
the right of the needle (23 & 24).
 If using the LSZ-1, rst put the machine in
straight stitch and center the needle bar.
Put the welting assembly under the groove
so the cord is accommodated by the groove
(25). The groove under the foot works to keep
the bulk of the material outside the arm of the
machine.
When sewing welting on an assembly, work
clockwise to ensure the bulk of the assembly
stays clear of the machine, i.e. out from under
the sewing machine arm (26).
Make Your Own Welting,
Cording and Piping
For how-to instructions, tips and advice
on making and sewing with welting,
cording and piping visit www.sailrite.com
23 24
25
26
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LS-1 Lubrication Points
Top side lubrication points
Ultrafeed®Maintenance
Lubrication
The machine was thoroughly oiled prior to shipment.
Oil all metal to metal working parts frequently!
Use only sewing machine oil.
After oiling, briey sew with scrap material to prevent soiling your work.
For good maintenance of your machine, you should oil it at least: twice yearly,
before it is put in storage, or anytime the machine sounds like it is running
roughly.
Marine Use & Potential for Rust
If the machine will be used or stored in a harsh environment, lubricate the working parts
of the machine with regular sewing machine oil prior to storage and before each use.
We also recommend using Boeshield’s T-9, a parafn based protectant, to protect
metal surfaces and control knobs. Use even on the painted surfaces, metal parts,
needle plates, and presser feet.
T-9 leaves a thin protective layer of wax. Use sparingly as a lubricant as wax buildup
can create gumming friction over time.
Right end lubrication points >
27
28
22
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Left end and back side lubrication points Underside lubrication points29 30
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LSZ-1 Lubrication Points
Left end and back side lubrication points
Top side lubrication points
Right end lubrication points >
31
32
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Underside lubrication points
Troubleshooting the Ultrafeed®
The more we understand our machines, the better they work for us. Ultrafeed®Sewing
machines are actually rather simple, and adjustments can be easy if you take a little
time to get to know your machine. Use this next section as a guide to better understand
your Ultrafeed® and to help ne tune and resolve common sewing machine problems.
Thread Tension Doesn’t Release
If your thread won’t pull out of the top of the machine, even after you’ve raised the presser foot,
the core (I) of your upper tension assembly (35) might have pulled away from the machine. To x
the tension, you will need to move the core closer to the machine.
1. Remove the left end cover (p. 49, 13) of
the machine, exposing the internal parts.
2. Using an Allen wrench, loosen the set
screw located directly behind the tension
assembly (p. 49, 12).
3. With the presser foot up, push the upper
tension assembly in until you feel the rst
signs of resistance.
4. Check to make sure the tension disks
(E& F) are open and that the thread
moves smoothly.
5. Tighten the set screw.
6. Put the presser foot down to check that
the tension disks properly tighten. The
thread should not easily pull through.
7. Replace the cover.
34
35 J I H G F E D C B A
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Clutch Will Not Disengage
If the clutch will not disengage, rst remove the reverse threaded Posi-Pin nut (p. 61, 2) from the
balance wheel (6). Remove the balance wheel. Polish and lubricate the Posi-Pin bushing shaft (4).
Slide the balance wheel back on and screw the Posi-Pin nut (2) down.
Removing the Hook to Clean the Shuttle Race
Guide Shaft and Free Thread Jams
Perform these steps with care:
1. Move the needle to its highest point by
turning the balance wheel toward you.
2. Remove the bobbin case/bobbin.
3. Turn each lever (36 A) one half turn away
from the retaining ring (B).
4. Pull the axle of the hook to remove
retaining ring (B) and hook (C).
5. Gently remove the accumulated lint and
thread from the retaining ring (B), hook
(C), and driver (D). Use a small brush to
clean the parts or blow out the debris.
6. Replace hook (C) opposite driver (D). The
hook just rests in place. Be sure the axle
is facing out.
7. Replace retaining ring (B) so that both
pins are under the black levers (A) when
turned. The polished side of the retaining
ring should be facing out.
8. Replace the bobbin and bobbin case
before beginning to sew.
Inconsistent Stitch Tension
If you notice that you are getting inconsistent stitch tension or if your thread looks loose and
sloppy near the tension assembly under operation, check your take up spring (p. 28, 35 H). If
the wire hook has broken off, you’ll need to replace the take-up spring. To do this, you’ll need to
disassemble the upper tension assembly. Keep track of how the parts are removed as they will
be replaced in the same manner (p. 28, 35).
1. Pull the cover knob (A) straight off (wiggle
a bit if needed).
2. Unscrew and remove the threaded
knob (B).
3. Remove the big spring (C), the spring
holder (D), the two tension disks (E& F),
and the keyway washer with pip (G).
4. Remove the old take-up spring (H) by
pulling it straight out.
5. Slide the new take-up spring over the
core post (I) so that the pip on the back
faces in towards the machine and the
straight arm of the spring faces down
(approximately at a 6 o’clock position).
Push the spring in all the way.
6. Spin the arm of the spring clockwise past
the slot in the core.
7. While holding the spring arm in place,
slide the keyway washer (G) back onto the
core with the pip facing in, so the take-up
spring arm rests on the metal pip of the
washer.
8. Replace the rst tension disk (F) with the
convex side facing out. Add the second
tension disk (E) with the concave side
facing out.
9. Replace the spring holder (D) with the
concave side facing out and the spring
(C). Screw the threaded knob (B) back on
the post and add the cover knob (A).
36
B
C
D
A
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Skipped Stitches
If your machine is skipping stitches, zigzag stitches will look like a straight stitch on
either the right or left side with proper zigzag stitches being formed only occasionally.
Straight stitches will have stitch lengths that look exceptionally long at times.
A skipped stitch means the gib hook is not catching the thread consistently.
There are a number of causes for skipped stitches.
Start with Step 1 and stop as soon as the problem is resolved.
1. Incorrectly Installed, Bent, or Dirty Needle
A bent needle will cause skipped stitches because the loop is not where the gib hook
(p. 55, 16) “expects” it to be. Adhesive residue on the needle will cause the thread to stick
to the needle instead of moving through the eye to form a loop.
Make sure your needle is installed correctly (p. 4), is not bent or damaged, and is free of any
residue from sewing adhesive material. Fouled needles may be cleaned with rubbing alcohol.
Bent or damaged needles must be replaced.
2. Not Enough Foot Pressure
Heavy, closely-woven materials like sailcloth and canvas can make the withdrawal of the
needle from the fabric difcult.
If the presser foot is being lifted as the needle comes out of the cloth the loop that the needle
forms will be too small.
Increase the downward pressure on the presser foot by tightening the pressure regulating
thumb screw (p. 12, 13).
3. Burred Gib Hook or Retaining Ring Cap Spring (37)
A needle strike to the gib hook (A) or the edge of the retaining ring cap spring’s “triangular”
opening (B) may result in a burr which can cause the thread to snag as it pulls through.
Remove any burrs by polishing them with emery paper or a ne le. If badly damaged,
replace with a new retaining ring cap spring (#1603).
4. Machine Has Gone Out of Timing
If skipped stitches continue, the machine has probably gone out of timing. The timing is
checked by determining the relationship of the needle to the gib hook point.
To reset the timing on your Ultrafeed®, follow the steps outlined on p. 40 "Ultrafeed®Timing".
Burred Area
Burred Area
>Retaining Ring Cap Spring>Gib Hook
37
A
B
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There are thread loops on the underside of the fabric:
A tangle on the bottom side of the fabric means there is not enough upper tension.
More than likely, the thread is not being pulled snugly between the tension disks
(p. 28, 35 E& F) on the upper tension assembly or is not between them at all.
1. Lift the presser foot (to push the two tension disks apart) (p. 12, 13)
2. Firmly pull the thread against the center shaft between the disks.
3. Drop the presser foot. The disks should close on the thread creating plenty of tension.
Gently pull on the thread to feel the tension.
4. If this did not solve the problem, pull the cover knob off the upper tension assembly and turn
the knob found underneath to the point where its outer surface is ush with the end of the
tension post. Then repeat steps 1–3.
Thread loops could also be caused by a burr on the retaining ring cap spring
(p. 32, 37 B). Remove any burrs by polishing them with emery paper or a ne le. If badly
damaged, replace with a new retaining ring cap spring (#1603).
Thread pulls out of the needle eye when starting to sew:
Conrm that the needle eye is threaded from left to right (p. 7, 6H& I). Then pull out a longer
thread tail and trap it with your nger. Release the thread tail after the rst few stitches.
A rat’s nest forms in the rst few inches of sewing and then clears up:
Eliminate this formation by trapping the thread tails from the needle and the bobbin as you start
to sew.
Thread Issues
Thread is shredding, balling or breaking:
There are a number of causes for breaking thread. Start with Step 1 and stop as soon
as the problem is resolved.
1. Incorrectly Installed or Damaged Needle
Make sure your needle is installed correctly (p. 4, 1& 2). Carefully inspect the needle for
burrs, warping or damage to the point that may be causing needle deection and shredding
the thread. Bent or damaged needles must be replaced.
2. Burred Gib Hook or Retaining Ring Cap Spring
A needle strike to the gib hook or the edge of the retaining ring cap spring’s “triangular”
opening may result in a burr which can cause the thread to snag as it pulls through
(p. 32, 37 A& B). Remove any burrs by polishing them with emery paper or a ne le.
If badly damaged, replace with a new retaining ring cap spring (#1603).
3. Incompatible Needle Size & Thread Weight
If the thread is too thick for the needle it will not pass through the needle eye and form a
loop and will instead ball at the needle. Check the compatibility of the needle size and thread
weight (p. 2).
4. Machine Has Gone Out of Timing
If the machine is out of timing it may cause the gib hook point to cut or shred the thread.
To reset the timing on your Ultrafeed®, follow the steps outlined on p. 40 "Ultrafeed®Timing".
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When stopping to turn a corner, the machine skips a stitch even with the
needle buried:
Bury only the needle tip in the cloth. This allows the machine to create the appropriately sized
loop for the gib hook to pickup. See p. 13 for helpful advice on turning corners.
When removing fabric from under the machine it pulls hard and three
strands of thread come up through the throat plate:
Typically this happens when fabric is being removed during the middle of a stitch. The hook
under the machine still has a loop of thread around it.
Before removing fabric from under the machine, manually turn the machine forward until the take-
up arm has just passed the top of its travel. This allows the hook to release the thread loop and
proper upper tension to be applied to nish the stitch (see p. 17).
Using Prolen Thread (PFTE)
Sewing with a lifetime (PFTE) thread can be difcult and frustrating at times. Try making a few
easy adjustments to your Ultrafeed® to improve the stitch quality when using Prolen. These are
general guidelines, feel free to experiment with these adjustments to ne tune your Ultrafeed®.
Stitches are skipped in straight or zigzag operation:
1. Mount the thread spool horizontally. Every time the thread pulls off the top of the cone,
a twist is put in the thread. Eventually, these twists add up and an erratic loop forms at the
hook. When the hook misses catching the thread loop, the machine skips a stitch. Make a
roller out of a dowel rod or an old coat hanger that will support the spool horizontally and
mount the spool on it. Pulling the thread off this way will reduce twists and kinks.
2. Further reduce the chance of twists and kinks in your thread by running it through all three
holes in the three hole thread guide (p. 50, 21) when threading the machine.
3. Use a #14 or #16 needle. PTFE thread is very slippery and often requires the use of a
smaller needle. If you are using a needle that is too large, the needle shaft cannot hold the
slippery thread rmly enough against the fabric to form a proper loop. This prevents the hook
from catching the thread loop and forming a stitch.
4. Lower the needle by 1/16". Lowering the needle has a tendency to increase the size of the
thread loop. Adjust the needle only if a smaller needle does not help.
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