Singer 635D-M

• Exact OEM application category; no unrestricted fabric weight or material capability inferred.

High-speed buttonholing for ordinary cloth and knit materials.

• Whip shows needle thread on top and bobbin thread below; purl pulls bobbin thread from both sides to the center. This does not establish other stitch types.

The manual distinguishes whip stitch and purl stitch, with different needle/bobbin thread formation and tension settings.

• Maximum specification only; actual fabric/thread, safe setup and installed drive may require lower speeds.

3600

• Exact model column, not width-scale value or universal plate/attachment clearance.

2.5–5mm

• Exact model column; wider exchanging-parts inventory does not expand this maximum.

6.4–25.4mm

• Switch off before unplugging. Running controls below are distinct from power-isolated setup and maintenance.

Turn off or unplug before threading, changing bobbin/needle/clamp or plate components, maintenance and when not operating.

• Electrical work requires qualified personnel. Stop for electrical damage; no motor wiring-box access or guard bypass.

Use trained operators, required safety devices and goggles, proper cable/connectors and grounding; repair, fitting and maintenance require trained personnel.

• Quiet servomotor warning is conditional; it does not prove this machine has a servomotor. Use complete head-handling instructions.

Keep belt cover and required safety devices installed, keep hands/clothes clear of rotating parts and isolate power before head handling or bobbin replacement.

• Power-isolated filling/access; guarded low-speed circulation observation is distinct. Read complete Figure12; no unstated oil grade substituted.

Fill with Singer oil toHigh; replenish below the oil-gauge bottom line and observe circulation through the sight-window pipe.

• Trained power-isolated work using full Figures12–14. Do not apply those intervals/doses to all components or invent a universal oiling recipe.

Clockwise hook-oil adjusting screws reduce supplied oil. Apply1–2drops to indicated other points weekly or every other week, and2–3drops atA for new or long-unused setup.

• Power-isolated maintenance; retain the original illustrated lubrication instructions.

Clean periodically with a dry soft cloth and no solvent material; after long disuse lubricate according to section3.9.

• Trained inspection; damaged electrical equipment is stopped and serviced by qualified personnel.

Check safety devices, head fixing screws, belt wear/tension, motor overheating and cable/connector damage.

• One combined OEM PDF, not separate instruction and parts originals or a service manual. Unknown distribution rights remain private.

Retained65-page English OEM Instruction Manual and Parts List,P/N364345-001 Rev1 October2011.

• Recommended setup only; actual installed motor, voltage, frequency and electrical configuration are not established.

The manual recommends a single- or three-phase400W(1/2HP) low-speed induction motor and requires M-type V-belts.

• Source-local original parts occurrences only; not a standardized presser-foot mount or retail fitment assertion.

Original source lists work-clamp check804270 and stitch plate804300.

• That table does not expand the exact S/M/L maximum buttonhole lengths. Geometry/row groups and applicable complete assemblies must be reviewed before a model-specific fitment claim.

The exchanging-parts table includes knife sizes6.3–38.1mm and associated clamp/plate/guide sets.

• Power-isolated trained installation using full Figures3–6; dimensions are setup references, not universal drive fit.

The head sits on the illustrated hinge/base; high- and low-speed belts use their separate pulley paths, approximately10mm slack and aligned motor pulley.

• Power-isolated setup. Keep the belt cover in place during operation.

Align cover guide pin with its hole and push until the cover snaps into place.

• Possible causes, not a diagnosis. Cam/drive adjustments require trained service and full instructions; do not reach running machinery.

For speed/stop/oil problems the table lists crank position, belt shifting/tension, cam setting, lubrication and reservoir/circulation as possible causes.

• Possible causes only. Timing, buffing or part replacement require trained service; no unrestricted thicker-needle or substitute-hook recommendation.

Thread breakage or loose stitches may relate to tension, spring stroke, threading, needle condition/size, burrs or hook timing.

• Match model/attachment conditions. The source’s0.5mm(1/2-inch) timing/needle-bar text is internally inconsistent and is not promoted as a repair dimension.

Skipped stitches may relate to a work-clamp check too large for the buttonhole or light-weight cloth.

• Power off, full illustrated route required; this summary does not replace the diagram.

Thread the needle thread in the order shown in Figure15.

• Operating control with required guards; distinguish emergency stop from electrical isolation before maintenance.

Hand-stop crank down toA reduces speed; the further motion toB stops the machine. The source notes pushing it down if it does not return.

• Confirm the needle is clear of fabric before turning the handle; retain the full operating sequence and power-isolated repair boundary.

Use the manual feed handle after emergency stop or thread breakage to position the cloth feed.

• Operating control only. Do not handle the knife or clear a jam while running.

Lightly hold the knife-stop lever until the machine stops when fabric should not be cut after sewing, such as following thread breakage.

• Power-isolated trained gear change with full cam-clearance table and figures. Do not infer that every listed gear is supplied or that an accessory expands model limits.

Pair spur gears with the same alphabetical mark; the rear gear’s engraved numeral gives stitch count. Circled source table marks identify included gears; others are optional.

• Trained power-isolated adjustment under complete section3.18. These are source setup targets, not universal settings for every thread/material.

For purl, the source gives approximately15–20g bobbin tension; for whip40–50g, with the specified exchange of tension-controller springs and separate controller adjustments.

• Trained power-isolated setup with the stated screw conditions. Keep separate from bobbin and controller tensions.

Purl take-up spring reference:6–8mm stroke and20–50g starting tension; source post rotation clockwise increases tension.

• Use exact model specification limits and full Figure25. Adjustment/attachment work requires power isolation; trial sewing is a separate guarded step.

Set the length pointer, retighten its nut and trial-sew so bar tacks are not cut; choose the work-clamp check approximately matching buttonhole length.

• Source control geometry under full Figures26–27; not model maximum width or alternate-part clearance. Do not cut the seam with the knife.

Actual overedging stitch width is half the scale value; source bar-tack width is twice stitch width. Keep the reference line clear of the knife and fine-adjust by trial sewing.