handi quilter HQ Stitch 710 Service Manual

handi quilter HQ Stitch 710 Service Manual

170 stitch variations
Table of Contents

Advertisement

HQ Stitch 710
Service Manual
05/29/18

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the HQ Stitch 710 and is the answer not in the manual?

Questions and answers

Summary of Contents for handi quilter HQ Stitch 710

  • Page 1 HQ Stitch 710 Service Manual 05/29/18...
  • Page 2: Table Of Contents

    Table of Contents Top Cover Removal (pages 2 and 3, HQ Stitch Technical Bulletin #0001) Machine Base Plate and Base Cover Removal Bed Cover Removal Belt Cover Removal Front Panel Removal 8-10 Free Arm Cover Removal 11-12 Lubrication 13-28 Feed Dog Height 29-31 Presser Bar Height and Radial Angle Needle Position (Front-to-Back)
  • Page 3 Table of Contents (cont.) Diagnostic Tests 01 -14: 75-88 •Test 01: Function of LCD, Buzzer, and LEDs • Test 02: Key (Button) • Test 03: BH (Button Hole Sensor) • Test 04: BO (Bobbin Winder Sensor) • Test 05: Presser Foot Lifter Switch •...
  • Page 4: Top Cover Removal (Pages 2 And 3, Hq Stitch Technical Bulletin #0001)

    It was set in the factory and should be correct unless someone has inadvertently changed it; e.g. tried to loosen it to remove the top cover. See HQ Stitch Technical Bulletin #0001: HQ Stitch 710 Pre-Tension Information, Preventing Bobbin Winding and Sewing Issues.
  • Page 5 Back Ground Information: The HQ Stitch 710 has two pre-tensions. Both are used for bobbin winding. Only the front pre-tension is used for sewing. If the machine is not threaded...
  • Page 6 The image below shows the bobbin winder pre- With the machine top cover removed one can see tension without the covers. Under the head of the the pre-tensioner screw lock nut. It should have screw there is a small spring, the two metal pre- about two metal threads showing above the nut as tensioner plates and an e-clip.
  • Page 7 Top Cover Removal (2 of 2) 3. Close the lid and lift up the handle. Remove the small Phillips screw on the left, needle end of the machine. 4. With the handle up, start to lift up on the left side of the top cover.
  • Page 8: Machine Base Plate And Base Cover Removal Bed Cover Removal

    Machine Base Plate and Base Cover Removal 1. Slide the accessory box off of the machine by pulling it to the left. 2. Gently lay the machine on its back. Locate the four screws on the base plate. Remove them completely and pull the plate off toward you.
  • Page 9: Belt Cover Removal

    Bed Cover Removal 1. Locate the two screws that hold the bed cover to the machine. Remove these two set screws. (Machine screws with fine threads) 2. First pull down on the end of the cover and second very gently start to slide the bed cover to the left.
  • Page 10 Belt Cover Removal 2. Carefully lift the machine back upright. Lift up on the handle and 1. Loosen the two washer screws a couple loosen the small washer screw a couple turns that hold the belt cover to the casting turns directly under the handle on the right side.
  • Page 11: Front Panel Removal

    Front Panel Removal (1 of 3) 1. Open the face plate on the left side of 2. Loosen a couple turns, but do the machine and locate the small not remove, the Phillips head washer Phillips head washer screw directly screw at the upper-right side of the behind the “Reverse”...
  • Page 12 Front Panel Removal (2 of 3) 4. Gently lay the machine down and 5. Using a flat head screwdriver, gently loosen the two Phillips washer screws push down on the open holes of the that hold the bottom of the panel to the casting directly behind the upper shaft.
  • Page 13: Front Panel Removal

    Front Panel Removal (3 of 3) Important: 4 conductor white plug with "blue", orange, red, brown; connects to middle center of "A" board Important: 4 conductor white plug with "yellow",orange, red, brown - connects to bottom center of "A" board 6.
  • Page 14: Free Arm Cover Removal

    Free Arm Cover Removal (1 of 2) 1. Remove the presser foot, shank, and 2. Gently lay the machine on its back. needle. Then, raise the presser bar to Locate the pin with a spring and c-clip its highest position. just to the left of the silver, feed cam fork on the bottom of the machine.
  • Page 15 Free Arm Cover Removal (2 of 2) Place machine back machine back upright on its feet. On the back side of the free arm locate and remove the silver, flat- head post on the inside of the free arm and the Phillips washer screw on the end of the free arm.
  • Page 16: Lubrication

    Lubrication Notes Factory Note: “Factory lubricated parts will provide years of household sewing without routine oiling. However, whenever the machine is being serviced, check to see if any parts need to be lubricated.”...
  • Page 17: Lubrication

    Appendix I: Lubrication Lubrication Notes 1. Oil: Put a drop of HQ Stitch oil on each point. 2. Grease: Put a small amount of HQ Stitch grease on each point. 3. Excessive lubrication can cause more harm than good. Use only a little lube in the right place.
  • Page 18 Oil – Put a drop of oil on the following: #1 The presser bar at the bottom bushing (inside the left hinged cover).
  • Page 19 Oil – Put a drop of oil on the following: #2 The top and bottom of the needle bar at the bushings (inside the left hinged cover).
  • Page 20 Oil – Put a drop of oil on the following: #3 The needle bar support top hinge pin oil orifice (seen after removing the top cover and the presser bar pressure adjusting knob).
  • Page 21 Oil – Put a drop of oil on the following: #4 The take up lever crank at the pitman, on both sides of the crank (seen through left hinged cover and after removing the top cover).
  • Page 22 Oil – Put a drop of oil on the following: #5 The take up lever connecting rod between the crank and the needle bar driver. Oil at both ends (inside the hinged cover).
  • Page 23 Oil – Put a drop of oil on the following: #6 Each side of the main shaft bearing, at the pitman side and the collar side, where play is taken out at the collar. (seen after removing the top cover). Note: The back bearing is a permanently sealed bearing.
  • Page 24 Oil – Put a drop of oil on the following: #7 The hook felt (under the needle plate and the bobbin case).
  • Page 25 Oil – Put a drop of oil on the following: #8 The bottom feed slider block and felt (seen from the top of the free arm after removing the two bottom covers and the free arm cover).
  • Page 26 Oil – Put a drop of oil on the following: #9 The upper feed shaft oil felt (found on the upper right rear of machine after removing the top cover).
  • Page 27 Oil – Put a drop of oil on the following: #10 The three oil felts near bushings on the lower timing shaft (seen after removing the two bottom covers and the bottom free arm cover).
  • Page 28 Oil – Put a drop of oil on the following: #11 The two pivot points on the bottom feed shaft (seen after removing the two bottom covers and the bottom free arm cover).
  • Page 29 Grease – Put a small amount of grease on the following: #12 The lower shaft hook timing gear, if needed. Make sure all lint is cleaned out of the gear first (seen after removing the left bottom cover of the bottom free arm cover).
  • Page 30 Grease – Put a small amount of grease on the following: #13 The feed fork and eccentric, center bottom of machine (seen after removing the left bottom cover and the bottom free arm cover).
  • Page 31 Grease – Put a small amount of grease on the following: #14 The white eccentric on the back of the pitman, clean first if dry, dirty or linty (seen after removing the top cover).
  • Page 32: Feed Dog Height

    Feed Dog Height (1 of 3) .8 - .9mm above the surface and level with the needle plate. 1. When the feed dogs are in their 2. Remove the foot, foot shank, and needle. highest position, they should be parallel The gauge with side A facing up at the rear with the needle plate and .8 - .9mm of the feed dogs.
  • Page 33 Feed Dog Height (2 of 3) This is a counter-threaded set screw. Turn it clockwise to loosen and counter clockwise to tighten – the opposite of normal! 5. Turn this small adjusting screw 6. To adjust the front section of the feed clockwise raise counter-...
  • Page 34: Feed Dog Height

    Feed Dog Height (3 of 3) This is a counter-threaded set screw. Turn it counter-clockwise to tighten. 9. Now, insert it into the empty-threaded Tighten counter-threaded 4mm hole. Turn it clockwise with a 2mm Phillips locking washer screw deep tool to raise and counter-clockwise to within the access hole;...
  • Page 35: Presser Bar Height And Radial Angle

    Presser Bar Height and Radial Angle (6mm when the presser bar is in its normal, up position with the standard zigzag foot attached) QM39401 1. Lower the feed dogs. Then, using the QM39401 step gauge, slide the 6mm gauge under the foot in the normal up position.
  • Page 36: Needle Position (Front-To-Back)

    Needle Position (Front-to-Back) 1. Remove the presser foot. Turn the hand wheel toward you to bring the needle within the needle plate hole. The needle should be directly in the middle of the hole. Important Note: If this adjustment is changed it will also change the relationship or distance between the needle and the hook point! That...
  • Page 37: Needle Position (Left-To-Right)

    Needle Position (Left-to-Right) 1. Turn the machine on and select straight- stitch, center needle position. Important note: When needle position is changed left to right it will also change the hook timing to the needle. When center needle position is changed it also changes needle positon of the zig zag.
  • Page 38 Needle-to-Feed Timing Theory and Check The following tests are best done with the machine powered on and with the stitch length set at the longest setting (5mm) Check #1 Turn the hand wheel in direction of motion. When the presser bar height is set correctly at 6mm and the presser foot is in the regular up position, the feed advance should be completed as...
  • Page 39: Needle-To-Feed Timing Theory , Check And Adjustment 35 And

    Needle to Feed Timing Adjustment (1 of 2) Note: The following procedure will 2. Slide the timing belt off of the lower affect machine hook timing – only do shaft gear. the following if necessary, when feed timing is not correct! Loosen the Phillip's screw that holds the idler which provides tension on the timing belt.
  • Page 40 Needle-to-Feed Timing Adjustment (2 of 2) 5. This picture shows the tip of the 6. While firmly holding the hand wheel needle flush with the top of the needle in place with one hand, slide the timing plate and the feed dogs flush with the belt onto the lower shaft with the other top of the needle plate when going in hand.
  • Page 41: Needle Bar Height

    Needle Bar Height (1 of 2) 1. Turn the machine on and select 2. Attach the needle bar height gauge straight-stitch, center needle with the black post sticking out toward position. Now remove the needle plate you. Be sure the gauge is all of the way and the presser foot with shank.
  • Page 42: Needle Bar Height

    Needle Bar Height (2 of 2) 5. As you continue to turn the hand wheel toward you, the needle bar height gauge should lightly skim the top of the gauge. There should not be a gap between the gauges and the needle bar height gauge should not hit the radial gauge enough to shift the needle bar sideways.
  • Page 43: Needle-To-Hook Clearance

    Needle-to-Hook Clearance (1 of 2) This is what we are looking for: 0 - 0.1mm clearance between the hook and the needle...
  • Page 44 Needle-to-Hook Clearance (2 of 2) Pivot point 1. With the machine off, push the 2. If an adjustment is needed, locate the needle bar to the left. Turn the hand three large Phillip's head screws on the wheel to bring the tip of the hook hook base plate.
  • Page 45: Hook Gear Backlash

    Hook Gear Backlash 1. Hold the hook race with your hand and wiggle it left and right. The hook race should have about .8mm of backlash, or ‘play’. Check it in three different spots by turning the hand wheel so the hook race turns 1/3 of the way each time.
  • Page 46: Needle-To-Hook Timing

    Needle-to-Hook Timing (1 of 2) 1. Remove the needle bar height gauge 2. Make sure the tip of the hook touches and install the needle-to-hook timing the bent down tab of the gauge. This is gauge. Make sure this timing needle necessary for both proper timing checks gauge is fully inserted.
  • Page 47: Needle-To-Hook Timing

    Needle-to-Hook Timing (2 of 2) 4. When the needle gauge is in its 5. Locate the two 2.5mm (tool size) lowest position, it should touch the hexagon screws holding the timing gear middle of the red line of the gauge. If to the lower shaft.
  • Page 48: Needle Threader Plate

    Needle Threader Plate 1. To remove the needle threader plate, 2. To replace it, place the new threader first remove the needle and then pull plate under the threader shaft. Push up down the threader. Push down on the on the threader plate until it snaps into threader plate close to the threader position.
  • Page 49 Upper Feed Dog Timing (1of 3) (Part 1) 2. Set the upper feed adjusting dial to 0. 1. Remove the needle and attach the If you have the belt cover removed, turn standard dual feed foot. Lower the presser the dial all way counter clockwise and foot with the lever on the end of the then three clicks clockwise.
  • Page 50 Upper Feed Dog Timing (2 of 3) (Part 1) 4. Using step gauge QM39401, check the clearance between the dual feed foot and the upper feed dog. The clearance should be 4mm. 5. To make an adjustment, locate and loosen the two hexagon set screws located near the hand wheel and bobbin winder assembly that...
  • Page 51 Upper Feed Dog Timing (3 of 3) (Part 1) 6. With the two hex screws loosened, you can now move the dual feed foot (the inside part of the foot) front-to- back freely. Move the moving part of the presser foot until it measures 4mm. 7.
  • Page 52: Upper Feed Dog Timing (Part 1)

    Upper Feed Dog Timing (Part 2) 1. With the upper feed dial set at "0" the gap between the two linkages should be 2.5mm. You could use the blade on the 2.5 mm tool as a gauge or the smallest step on the left of the step gauge is 2.7mm, so it should be a very tight fit inside the gap or just not fit into the gap.
  • Page 53: Needle Plate Microswitch

    Needle Plate Microswitch 11.5mm 1. Reattach the needle plate by hooking 2. The top of the surface of the silver, the metal tabs on the left of the needle micro switch bracket bottom plate under springs that surface of the needle plate should be attached to the thread cutter.
  • Page 54: Thread Tension Unit Adjustments

    Thread Tension Unit Adjustments 1. If there is no tension, check the thread tension release bracket. When the presser foot is down, the distance between the silver post and the black bracket that forces the discs open should be .8-1.0 mm. To make an adjustment, loosen the small Phillips screw directly behind the c-clip and pivot the silver post left or right accordingly.
  • Page 55: Automatic Thread Cutter Removal, Adjustments, And Installation

    Automatic Thread Cutter Removal, Adjustments, and Installation (1 of 4) 1. To remove the thread cutter unit from the machine, first remove the two large Phillips screws on the end of the cutter. As you remove the screws, the thread cutter will want to fall, so make sure you hold it in your hand.
  • Page 56 Automatic Thread Cutter Removal, Adjustments, and Installation (2 of 4) 4. Pull the long extending blade all the way out Setting plate and back in again, ensuring it slides smoothly. Clean the thread cutter of lint and debris on both the top and underside of the cutter. Put a small drop of oil on the underside of the long extending blade.
  • Page 57 Automatic Thread Cutter Removal, Adjustments, and Installation (3 of 4) 7. If you continue to have issues with the thread cutter, such as cutter errors, the thread cutter unit will need to be replaced. Remove the Phillips screw and wire clip. 8.
  • Page 58: Automatic Thread Cutter Removal, Adjustments, And Installation

    Automatic Thread Cutter Removal, Adjustments, and Installation (4 of 4) 10. Align the thread cutter with the step motor. 11. When reattaching, the black post of the The black post must fit into the hole of step motor must fit into the access hole of the the thread cutter thread cutter plate.
  • Page 59: Stretch Stitch Feed Balance

    Stretch Stitch Feed Balance (1 of 2) 1. While pressing the needle up/down 2. The LCD displays “--------”. Press the and lockstitch buttons, turn the machine “8” key. 3. Set the stretch stitch balance dial 4. Using the “F” satin stitch foot and straight up and down as shown .
  • Page 60 Stretch Stitch Feed Balance (2 of 2) 5. The correct distance between six of the 8s as shown should be 33 to 39mm. 35mm 33-39mm 6. If it isn’t, press the right arrow key to bring the adjusting screw into position. Locate the hex screw on the feed adjusting bracket.
  • Page 61: Parts Of The Front Panel

    Parts of the Front Panel See page 8 for wire colors and connectors removed earlier 1. Circuit Board ‘L2’ (Horizontal LED Light) 2. Slide Volume (Speed Control) 3. Circuit Board ‘L1’ (Horizontal LED Light) 4. Circuit Board ‘A’ 5. Circuit Board ‘F’: •...
  • Page 62: Printed Circuit Board A Removal

    Printed Circuit Board A Removal 1. Carefully hook your finger under the loop of the brown flexible cable and pull upward. Do not grab the cream-colored connector, as this is soldered to the board. 2. Unplug the four sets of wires on the upper-right side of the board.
  • Page 63: Printed 'A' Circuit Board Diagram

    PRINTED CIRCUIT BOARD ‘A’ DIAGRAM See page 8 for wire and connector colors PRINTED CIRCUIT BOARD L2 PRINTED CIRCUIT BOARD L1 BOBBIN WINDER SWITCH PRINTED CIRCUIT BOARD L2 (FACE PLATE LAMP) BH SENSOR NEEDLE PLATE MICRO SWITCH FOOT CONTROLLER PRESSER FOOT LIFTER MICRO SWITCH FEED DOG DROP STEP blue, orange, red, brown...
  • Page 64: Touch Panel Replacement

    Touch Panel Replacement (1 of 2) 1. If the touch panel does not respond 2. Very carefully work your way around to touch, screen calibration does not the edges of the touch panel sheet with hold, or the screen is scratched, remove your hand to release it from the panel.
  • Page 65: Touch Panel Replacement

    Touch Panel Replacement (2 of 2) 5. Place the touch panel cover into position and replace the six Phillips screws. 6. Lay the ‘A’ board back into position and replace the three Phillips screws. Next, plug the four connectors and the flexible cable back into the ‘A’...
  • Page 66: Dc Motor Removal And Installation

    DC Motor Removal and Installation 1. Slide the motor belt off of the hand 2. Unplug the DC motor wire from the wheel. back of the A board. It is the plug with the wires wrapped in clear tubing at the bottom of the ‘A’...
  • Page 67: Switching Power Supply Removal And Installation

    Switching Power Supply Removal and Installation (1 of 2) 1. Remove the three Phillips screws that hold this unit to the machine. Once removed, the unit will slide outward. Note you do not need to remove the rear cover to remove the power supply.
  • Page 68 Switching Power Supply Removal and Installation (2 of 2) 4. After installing the new power supply, 5. Set the guide into place. Before guide the wires behind the plastic wire tightening the washer screw, lightly pull guide. Be careful not to pinch the wires. on the wires verifying they are not pinched.
  • Page 69: Free Arm Cover Installation

    Free Arm Cover Installation 1. Remove the needle plate. Reattach ¼-inch gap the free arm cover by setting it into position about ¼ inch from the inside of the free arm. Important: Be sure to push down on the end of the cover while pushing in the cover.
  • Page 70: Front Panel Installation

    Front Panel Installation (1 of 2) 1. Align the front panel with the machine. Plug the 14 wires into the A board. It’s best to start from the bottom and work your way up. Then, attach the front panel ensuring there are no gaps between the covers.
  • Page 71 Front Panel Installation (2 of 2) 3. While lightly pushing in on the front 4. Looking through the right side of panel, tighten the set screw directly in the machine below the hand wheel front of the handle on the right side. and behind the timing belt;...
  • Page 72: Bed Cover Installation

    Bed Cover Installation 1. Guide the bed cover into position. Be careful how you pull it because there are wires underneath and you do not want to scratch or cut them. 2. Replace the two set screws that hold the cover to the machine.
  • Page 73: Belt Cover Installation

    Belt Cover Installation 2. Replace the long Phillip's head screw 1. Align the belt cover with the machine directly under the hand wheel. and fit it into position. 4. Gently lay the machine down on its 3. Lift the handle up and tighten the back.
  • Page 74: Machine Base Plate And Base Cover Installation

    Machine Base Plate and Base Cover Installation 1. To replace the machine base plate without scratching it, lift the end of the machine up slightly by grabbing the free arm and fit it into position. Replace the four self-tapping set screws.
  • Page 75: Top Cover Installation

    Top Cover Installation Important: Do the following so you only have to put the top cover on once! Presser Bar knob on first before the top cover, then cover with lid closed and handle up! 1. Lift the handle up, insert the top cover unit starting from the right side, and fit it into position.
  • Page 76: Touch Screen Calibration

    TOUCH SCREEN CALIBRATION (1 of 2) 1. While holding down the 2. Four dashes will appear needle up/down & lockstitch on the screen. Press the buttons, turn the machine on. lockstitch button. 4. Using a stylus press the 3. After pressing the lockstitch bottom left corner of the LCD.
  • Page 77: Touch Screen Calibration

    TOUCH SCREEN CALIBRATION (2 of 2) 5. Next press the middle of the #6 on 6. Next press the top right corner of the the LCD to get “t3”. LCD for “t4” 7. Next press the middle of the start over 8.
  • Page 78: Diagnostic Tests

    Diagnostic Test 01 / Function of LCD, Buzzer and Lamp 1. While holding down the needle 2. After “- - - - " appears on the screen, up/down and lockstitch buttons, turn the release the buttons. machine on. 3. Press the 1 key to proceed. 4.
  • Page 79: Test 02: Key (Button)

    Diagnostic Test 02 / Key (Button) Note on each step: if the test result is the correct condition, press the start/stop button to proceed to the next step. If the result is a defective condition, press the reverse stitch button to proceed to the next step. This will track the defective conditions on the screen when finished.
  • Page 80: Test 03: Bh (Button Hole Sensor)

    Diagnostic Test 03 / BH (Buttonhole Sensor) 1. When the buttonhole lever is all of 2. When the buttonhole lever is pulled the way up, the display should read all of the way down and moved in the “BH”. sensor, the buzzer sounds and LCD displays BH symbol.
  • Page 81: Test 04: Bo (Bobbin Winder Sensor)

    Diagnostic Test 04 / BO (Bobbin Winder Switch) 1. LCD displays “04 and “BO”. 2. When the bobbin winder is moved to the right, buzzer sounds and LCD displays the bobbin winder symbol. When the bobbin winder spindle is moved to the left, buzzer sounds and the bobbin winder symbol disappears.
  • Page 82: Test 05: Presser Foot Lifter Switch

    Diagnostic Test 05 / Presser Foot Lifter Switch 2. In the normal up position, one up 1. Move the presser foot up and down. arrow appears on the screen with the The ”05” will be displayed along with the foot symbol. When the foot is raised to foot icon.
  • Page 83: Test 06: Ph (Phase Or Lower Shaft Shield Positioning Sensor)

    Diagnostic Test 06 / PH (Phase or Lower Shaft Shield Positioning Sensor) 1. Turn the hand wheel toward you. Lower the needle bar from its highest to lowest position. A buzzer sounds and the LCD displays the stitch length symbol when the machine is at feed phase.
  • Page 84: Test 07: Stm (Zig Zag Step Motor And Feed Motor)

    Diagnostic Test 07 / STM (Zig Zag Step Motor and Feed Motor) 1, Raise the needle bar to its highest position. The stitch width symbol will be displayed. Press the needle up/down button. The zigzag motor will be initialized and get its default position. Buzzer sounds and motor initializes.
  • Page 85: Test 08: Fc (Foot Control)

    Diagnostic Test 08 / FC (Foot Control) 1. When test 08 is selected, the LCD displays “08” and “FC”. Attach the foot control to the machine. Depress the foot control as far as it goes and then release it. 2. The foot control symbol appears when the foot control is attached.
  • Page 86: Test 09: Slide Volume

    Diagnostic Test 09 / Slide Volume 1. LCD displays “09” and “Slide”. Shift the slide volume from right to left position. Buzzer will sound and arrow mark appears at the left-most positon. 2. Return the slide to the right. Buzzer will sound and the arrow mark will appear at the right-most position.
  • Page 87: Test 10: Dc (Motor)

    Diagnostic Test 10 / (DC) Motor 1. LCD displays “10” and “DC”. Note: the presser foot must be down. 2. Press the needle up/down button. Machine runs slow, then fast, and the needle bar stops at the highest position. 3. Fault note: The machine motor does not start.
  • Page 88: Test 11: So (Thread Tension Release Solenoid)

    Diagnostic Test 11 / SO (Thread Tension Release Solenoid) 1. LCD Displays “11”, “SO” and “off”. Lower the presser foot and press the needle up/down button. Note: The thread tension disk opens , and the LCD displays “ON” while the thread tension disk opens.
  • Page 89: Test 12: Cut (Thread Cutter Motor, Cutter Solenoid)

    Diagnostic Test 12 / Cut (Thread Cutter Motor, Thread Cutter Solenoid) 1. LCD displays “12” and “Cut”. Turn the hand wheel toward you to raise the needle bar to its highest position. Press the needle up/down button. 2. Press the needle up/down button. The thread cutter symbol will blink, and the thread cutter motor will be initialized.
  • Page 90: Test 13: Feed Dog

    Diagnostic Test 13 / Feed Dog 1. The LCD displays “13” and the feed dog symbol. When the drop lever is turned to the right, or to the rear of the machine, the feed dogs are up and the LCD displays down arrows under the feed dog symbol (indicating the way the feed dogs will go when the lever is activated).
  • Page 91: Test 14: Ps (Needle Plate Sensor)

    Diagnostic Test 14 / PS (Needle Plate Sensor) 1. LCD displays only “14” when it has no needle plate installed. 2. With the zigzag plate installed, the LCD displays 14 and PS Z and with the straight stitch needle plate installed, the LCD displays 14 and PS 3S.
  • Page 92: Appendix Ii: Diagnostic Tests

    Appendix II: Diagnostic Tests...
  • Page 93 HQ Stitch 710 Diagnostic Test Appendix NOTE: 1. Be sure that the power switch is turned off when replacing parts. 2. The language on the LCD is English only. Preparation 1. Shift the bobbin winder spindle to the right. 2. Turn the drop feed lever to the right (away from you) to raise the feed dog.
  • Page 94 STEP AND PROCEDURE CORRECT CONDITION DEFECTIVE CONDITION ITEMS T CHECk Turn on the power switch while Sewing lamp and LCD backlight lit. “1” button is not responding. LCD displays “----”. Sewing lamp does not lit. FUNCTION OF simultaneously pressing the LCD backlight does not lit.
  • Page 95 STEP AND PROCEDURE CORRECT CONDITION DEFECTIVE CONDITION ITEMS TO CHECk LCD displays “05” and presser foot Buzzer does not sound. Move the presser foot lifter up and Presser foot symbol does symbol. down. PRESSER not change. When the presser foot lifter is raised, FOOT If the result is correct condition, LIFTER...
  • Page 96 STEP AND PROCEDURE CORRECT CONDITION DEFECTIVE CONDITION ITEMS TO CHECk Attach the foot control to the LCD displays “08” and “FC”. The foot control symbol machine. does not appear. FOOT Depress the foot control as far as Buzzer does not sound. CONTROL it goes, then release it.
  • Page 97 STEP AND PROCEDURE CORRECT CONDITION DEFECTIVE CONDITION ITEMS TO CHECk Turn the handwheel toward you to LCD displays “12” and “Cut”. Thread cutter motor does raise the needle bar at its highest not work. The thread cutter symbol will blink, and THREAD position.
  • Page 98 Buzzer sounds after few seconds when the self-diagnostic test has been finished. The test result has been determined. CORRECT: Buzzer sounds and LCD displays “00” DEFECTIVE: Caution buzzer sounds and LCD displays the defective part number. Refer to page 36-39 and fix the defective part. The defective test number.
  • Page 99: Supplement: Mechanical Adjustments

    Supplement: Mechanical Adjustments This supplement covers the same information contained in this service manual. Use it as necessary for further clarification about making adjustments to the HQ Stitch 710.
  • Page 100 INDEX CHANGING EXTERNAL PARTS Face cover ............................1 Top cover .............................1 Belt cover ............................2 Machine base ............................3 Base cover ............................3 Bed cover ............................3 Free arm cover ............................4 Front cover ............................5 Rear cover ............................6 REPLACING ELECTRONIC COMPONENTS Printed circuit board A .........................7 Printed circuit board F .........................8 Switching power supply unit ........................9 Driving motor .............................10...
  • Page 101 Changing External Parts (1)   Face cover Face cover Setscrew A To remove: 1. Remove the setscrews A. Remove the face cover. To attach: 1. Follow the above procedure in reverse. Top cover Top cover Setscrew B Carrying handle To remove: 1.
  • Page 102 Changing External Parts (3) Setscrew A Machine base Setscrew A Machine base To remove: 1. Remove the setscrews A. 2. Remove the machne base. To attach: 1. Follow the above procedure in reverse. Setscrew A Setscrew A Base cover Setscrew B Base cover Setscrew B To remove:...
  • Page 103 Changing External Parts (4) Needle plate release lever Free arm cover Needle plate To remove: 1. Remove the machine base and base cover (see page 3). Press the needle plate release lever to remove the needle plate. Free arm cover Setscrew 2.
  • Page 104 Changing External Parts (5) Front cover Setscrew A Setscrew A To remove: 1. Remove the top cover, belt cover, base cover, machine base and free arm cover (see pages 1-4). 2. Loosen the setscrews A (inside of the machine base). Setscrew B 3.
  • Page 105 Changing External Parts (6) Setscrews A Rear cover Rear cover To remove: 1. Remove the top cover, mahine base, base cover and free-arm cover (see pages 1, 3 and 4.) 2. Remove the setscrew A. Setscrews B 3. Remove the setscrew B. Setscrews C Rear cover 4.
  • Page 106 Replacing electronic components Printed circuit board A Setscrew NOTE: Do not disconnect the connectors by pulling on cord. To disconnect the connectors, grasp the connector, not the cord. To remove: 1. Remove the front cover. 2. Grasp the connector directly with your fingers and pull. Do not pull the lead wire, as this may damage the contact sleeve inside the connector.
  • Page 107 Replacing electronic components Printed circuit board F o remove: 1. Remove the front cover (see page 5). 2. Disconnect the connectors from the circuit board A (see page 7). 3. Remove the CS rings. 4. Remove the setscrews, and the circuit board F. To attach: CS rings 1.
  • Page 108 Replacing electronic components Switching power Switching power supply unit supply connector Cord guide plate Setscrew A To remove: 1. Remove the belt cover, the top cover and the front cover (see page 1, 2 and 5). 2. Loosen the setscrew A. Remove the cord guide plate. 3.
  • Page 109 Replacing electronic components Driving motor To remove: 1. Remove the belt cover, the top cover and the front cover (see pages 1, 2 and 5). 2. Remove the motor belt. 3. Disconnect the driving motor connector from the printed circuit board A. 4.
  • Page 110 Replacing electronic components Setscrew A Thread tension unit To remove: 1. Remove the belt cover and the top cover (see pagesf 1 and 2). 2. Remove the front cover (see page 5). 3. Disconnect the Solenoid 1 thread tension release connector from the printed circuit board A (see page 7).
  • Page 111 Mechanical adjustment Feed dog height When the foot pressure dial is at “7” and the presser foot A is lowered, the highest position of the feed dog should be 0.80 to 0.90 mm from the surface of the needle plate. Adjustment 1: 1.
  • Page 112 Mechanical adjustment Needle drop position When the straight stitch is selected, the needle should be positioned in the center of the needle plate hole. When the needle drop position is set at "0.0" and "9.0", the clearance between the side of the needle and the needle hole should be 0.2 mm or more.
  • Page 113 Mechanical adjustment Presser bar height The clearance between the presser foot and the surface of the needle plate should be 6 mm when the presser foot is raised. The presser foot (zigzag foot A) should be pararell to the slot of the feed dog teeth when attached. To adjust: 1.
  • Page 114 Mechanical adjustment Hook timing The amount of ascending travel of the needle bar from its lowest position to the position (Needle drop position 0.0) where the tip of the rotary hook exactly meets the right side of the needle should be 3.70 to 4.00 mm (Needle drop position 0.0) To adjust: Needle #14...
  • Page 115 Mechanical adjustment Needle bar height The distance between the upper edge of the needle eye and the hook race should be in the range of 1.6 to 2.0 mm when the tip of the hook meets right side of the needle in the needle drop position "0.0" as the needle ascends from its lowest position.
  • Page 116 Mechanical adjustment Clearance between needle and tip of the rotary hook The clearance between the needle and the point of hook should be -0.1 to +0.05 mm. Adjustment 1 1. Remove the top cover (see page 2). Needle plate hole 2.
  • Page 117 Adjustment 2 1. Remove the bed cover (see page 3). 2. Turn the power switch ON, and select the zigzag stitch pattern 9. Setscrew C Setscrew A Adjust the stitch width at its maximum (9.0). 3. Remove the presser foot, needle plate and bobbin holder.
  • Page 118 Mechanical adjustment Presser bar lifter switch position adjustment To check: 1. While pressing the needle up/down and lock stitch Presser foot symbol buttons, turn the power switch on. The LCD displays "----". 2. Press "5" key to enter the sesor test mode. 3.
  • Page 119 Mechanical adjustment Backlash between hook drive gear and lower shaft gear The rotary play of the hook should be 0.8 mm or less when the tip of rotary hook is within the width of feed dog. 1. Remove the base cover and bed cover (see page 2 and 3). 2.
  • Page 120 Mechanical adjustment Upper shaft shield plate position When the machine is set for zigzag stitch, the needle should start to swing 7.2 to 8.2 mm above the surface of the needle plate. To check: 1. Attach the needle #14. 2. While pressing the needle up/down and lock stitch Needle #14 buttons, turn the power switch on.
  • Page 121 Mechanical adjustment Upper thread tension The standard upper thread tension should be 75 to 90 grams when pulling the thread (while polyester thread size 50) at the speed of 110 mm/sec with the tension at "AUTO" (Be sure the presser foot is lowered). 1 Set the thread tension dial to "AUTO".
  • Page 122 Mechanical adjustment Needle threader plate If the hook of the threader plate is damaged, change or adjust the part as follows: To remove: 1 Push down the needle threader knob and pull the needle threader plate (A) down to remove it (see Fig.
  • Page 123 Mechanical adjustment Thread drawing lever The standard height of the thread drawing lever from the surface of bobbin holder should be in the range of 5.5 – 6.0 1. Remove the presser foot, the needle plate and the Thread drawing lever bobbin holder.
  • Page 124 Mechanical adjustment Upper feed dog (1) The clearance between the upper feed link shaft and upper feed lower shaft should be 2.5 mm when the upper feed adjusting dial is set to "0". To check: 1 Remove the belt cover and base cover (see page 1 and 2).
  • Page 125 Mechanical adjustment Upper feed dog (2) The clearance between the dual feed foot and upper feed dog should be 4 mm when the stitch length is set at "0". * Check the upper feed dog (1) (see page 26) before this adjustment. To check: 1.
  • Page 126 Mechanical adjustment Upper feed dog (3) The tip of the needle height should be 0 to 1 mm above the surface of the needle plate when the toe of the dual feed foot touch the needle plate. To check: Fig. 2 1.
  • Page 127 To adjust: Setscrew select straigh stitch. 1. Turn the power switch on and (Be sure that the machine is not locked.) Turn the drop feed lever to drop the feed dog. Press the adjusting key and set the stitch length at "0". Turn the upper feed adjusting dial to set the dial at "0".
  • Page 128 Mechanical adjustment Buttonhole lever adjustment To prepare: 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on. The LCD display “----”. Press “5” key to enter the sesor test mode. 2. Attach the automatic buttonhole foot R. Place a piece of paper between the presser foot and the needle plate for easier adjustment.
  • Page 129 Mechanical adjustment Thread cutter The distance between the end of thread cutter plate slit and the edge of moving cutter should be in the range of 0.4 to 1.2 To check: 1. Remove the bed cover and free arm cover (see page 3, 4). 2.
  • Page 130 Mechanical adjustment Solenoid position adjustment When the tension disk is closed, the clearance between the plunger and the end of yoke should be 2.0 mm. TOP VIEW [To check] 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on. The LCD display “----”.
  • Page 131 MECHANICAL ADJUSTMENT Stretch stitch feed balance Adjust the stretch stitch balance dial C at the setting mark D. The measurement of five of test patterns should be in the range of 33 to 39 mm as shown. To adjust: 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on.
  • Page 132 Mechanical adjustment Needle plate switch Fig. 1 To check and adjustment: Needle plate sensor 1. Prepare the needle plate and the needle plate for straight stitch. 2. Insert the needle plate base plate under the fixed cutter ◎ spacer and the slide plate positioning plate. Press the mark to attach the needle plate.

Table of Contents