How to Mod a Seiko Watch: Complete Step-by-Step Tutorial (2025)

How to Mod a Seiko Watch: Professional Tutorial for Custom Builds

Building your own custom Seiko mod watch is one of the most rewarding experiences in watchmaking. Whether you want to create a unique dive watch, build a vintage-inspired timepiece, or simply learn the inner workings of mechanical watches, modding a Seiko watch offers an accessible entry point into horological craftsmanship.

In this comprehensive tutorial, you'll learn exactly how to mod a Seiko watch from start to finish—including which tools you'll need, where to source quality parts, detailed step-by-step assembly instructions, and professional tips to avoid common mistakes.

By the end of this guide, you'll have the knowledge to build your first custom Seiko mod watch with confidence.

What You'll Learn:

· Essential tools and parts needed for Seiko modding

· Step-by-step assembly process (with detailed instructions for each component)

· Professional techniques for hand alignment, crystal installation, and pressure testing

· Common mistakes and how to avoid them

· When to DIY vs. hiring a professional modder

Time Required: 3-6 hours for your first build, 1-2 hours with experience

Skill Level: Beginner-friendly with patience; no prior watchmaking experience required

Estimated Cost: $200-$600 depending on parts quality

What You'll Need: Tools & Parts Checklist

Essential Tools (One-Time Investment: $50-$150)

Before you start modding Seiko watches, you'll need these fundamental tools:

Basic Tool Kit:

1. Case Opening Knife or Case Back Opener ($8-$15)

· Jaxa-style knife for snap-back cases

· Adjustable wrench-style for screw-down case backs

· Recommendation: Get both types for versatility

2. Hand Removal Tool ($5-$10)

· Prong-style hand puller

· Essential for removing hour, minute, and second hands without damage

· Pro Tip: Plastic versions reduce risk of dial scratches

3. Hand Setting Tools ($8-$12)

· Hand press or hand setting levers

· Used to install hands onto movement without applying uneven pressure

· Critical: Proper hand setting prevents misalignment and hand collision

4. Rodico or Blu-Tack ($5-$8)

· Reusable adhesive putty for handling small parts

· Picks up dust, fingerprints, and debris from dials

· Essential for keeping your build clean

5. Precision Tweezers ($10-$20)

· Anti-magnetic, non-serrated tips

· Sizes: 3, 5, and 7 (different tip shapes)

· Used for handling small parts like dial feet, springs

6. Movement Holder ($12-$18)

· Keeps movement stable during assembly

· Prevents rolling and damage

· Various sizes available (get one compatible with NH35/NH38)

7. Crystal Press ($25-$80)

· For installing crystals without cracking

· Hand-press style (budget) or bench-mounted (premium)

· Includes multiple dies for different crystal sizes

8. Spring Bar Tool ($6-$12)

· For strap/bracelet installation

· Forked and pointed ends

· Essential for final assembly

Optional But Recommended Tools:

9. Bench Vise or Repair Stand ($20-$40)

· Holds case steady during assembly

· Rubber jaw covers prevent scratching

10. Loupe or Magnification ($10-$30)

· 10x magnification minimum

· Essential for inspecting dial feet, hand alignment

· LED-lit versions recommended

11. Dust Blower ($8-$12)

· Removes dust from dial and crystal before assembly

· Compressed air can work but hand blowers are safer

12. Waterproof Testing Tools ($15-$50)

· Vacuum tester or pressure tester

· Critical if you plan to swim/dive with your mod

· Alternative: Pay for professional testing ($20-$30)

Total Tool Investment: $150-$350 for complete setup (tools last for many builds)

Parts Needed for Your Seiko Mod Build

Here's what you'll need to complete a standard Seiko mod watch:

Core Components:

1. Movement ($40-$80)

· NH35A (with date) - Most popular, $40-$50

· NH36 (identical to NH35, just different manufacturer designation)

· NH38 (no date) - For cleaner dial designs, $45-$55

· Source: eBay, AliExpress, Namoki Mods, Crystaltimes

· Pro Tip: Buy genuine Seiko movements, not clones

2. Case ($30-$120)

· Determines overall style (Submariner, Explorer, Seamaster, etc.)

· Sizes: 38mm-44mm (40-42mm most versatile)

· Material: Stainless steel 316L (standard), titanium (premium)

· Water resistance capability: 100m-200m typical

· Quality Check: Look for well-finished edges, smooth threads

3. Dial ($15-$80)

· Must match case diameter and movement feet position

· NH35/36 dials need 3 o'clock date window

· NH38 dials have no date window

· Finishes: Sunburst, matte, textured, meteorite

· Compatibility: Verify dial feet at 3:00 and 9:00 for NH movements

4. Hands Set ($10-$35)

· Must be compatible with NH35/NH38 stem height

· Typical measurements:

· Hour hand: 1.50mm opening

· Minute hand: 0.90mm opening

· Second hand: 0.20mm opening

· Styles: Mercedes, Sword, Snowflake, Dauphine

· Critical: Ensure hands don't touch each other or dial

5. Chapter Ring (Optional, $8-$15)

· Fits between dial and crystal

· Provides minute track markings

· Must match case diameter

6. Bezel Insert ($12-$45)

· Aluminum (budget, vintage look) - $12-$20

· Ceramic (premium, scratch-resistant) - $25-$45

· Sapphire (ultra-premium) - $60-$100

· Popular styles: Pepsi, Batman, basic black

7. Crystal ($15-$50)

· Mineral crystal (budget) - $10-$15

· Sapphire crystal (recommended) - $25-$50

· Options: Flat, domed, AR-coated (anti-reflective)

· Size: Must match case specifications exactly

8. Gaskets ($5-$12 for set)

· Case back gasket

· Crystal gasket

· Crown gasket

· Critical for water resistance - Always replace with fresh gaskets

9. Crown ($8-$25)

· Screw-down (better water resistance) or push-pull

· Size must match case crown tube

· Signed (with logo) or unsigned (sterile)

10. Case Back ($10-$30)

· Typically included with case

· Styles: Display (exhibition) or solid

· Screw-down or snap-back

Parts Sources:

· USA: Namoki Mods, Crystaltimes, DLW Watches, Lucius Atelier

· International: AliExpress (budget), eBay, Tokeilab (Japan)

· Premium: DLW Watches, Yobokies (limited availability)

Total Parts Cost: $200-$600+ depending on quality tier

Step-by-Step: How to Mod a Seiko Watch

Before You Begin: Workspace Preparation

Create a Clean Workspace:

1. Cover work surface with white microfiber cloth (shows dropped parts easily)

2. Work in well-lit area (natural daylight or LED lamp)

3. Wash hands thoroughly, allow to dry completely

4. Remove any jewelry that could scratch parts

5. Organize parts in small compartments or tray

6. Have all tools within reach

Pro Tip: Work on one section at a time. Don't open all packaging simultaneously—this increases dust contamination risk.

Step 1: Install Dial Onto Movement (15-20 minutes)

This is your first and most critical step, as the dial is the foundation for the rest of your build.

Detailed Instructions:

1.1 - Prepare the Movement

· Remove NH35/NH38 movement from packaging using tweezers

· Place movement in movement holder with dial side facing up

· Inspect movement for any shipping damage (bent stem, debris)

1.2 - Identify Dial Feet Position

· Examine dial back—you'll see 2 small posts (dial feet) at 3:00 and 9:00 positions

· NH35/NH36 dials: Verify date window is at 3 o'clock

· NH38 dials: No date window needed

1.3 - Align Dial Feet with Movement Holes

· Locate the two dial feet holes on the movement (small brass-colored openings)

· Using tweezers, carefully position dial so feet align with holes

· Critical: Do NOT force—dial should seat naturally with minimal pressure

1.4 - Seat the Dial

· Once aligned, gently press dial down using finger or soft tool

· Dial should sit flush against movement

· Verify dial doesn't rock or have gaps

1.5 - Secure with Dial Dots (If Feet Don't Fit)

· If dial feet don't match your movement (rare), use adhesive dial dots

· Place 2 small dial dots at 12:00 and 6:00 positions on movement

· Press dial onto dots gently but firmly

· Warning: This is a permanent bond—ensure alignment before pressing

Common Mistakes at This Step:

· ❌ Bending dial feet during installation (leads to dial wobble)

· ❌ Leaving fingerprints on dial face

· ❌ Misaligning date window with movement date wheel

Verification:

· Dial sits completely flat against movement ✅

· No gaps or rocking motion ✅

· Date window aligned (for NH35/36) ✅

· No dust or fingerprints on dial surface ✅

Step 2: Install Hands (20-30 minutes)

Hand installation is the most delicate step. Improper installation causes 80% of DIY mod failures.

Detailed Instructions:

2.1 - Set Date to "15" Position

· Turn crown to advance date to "15"

· Reason: This position prevents accidental hand/date wheel contact during installation

2.2 - Install Hour Hand

· Using tweezers, pick up hour hand by the edges (never touch center hole)

· Align hour hand hole with hour wheel post (shortest, thickest post in center)

· Lower hand vertically onto post

· Using hand press or setting tool, apply gentle downward pressure

· Critical: Press straight down—angled pressure bends the hand

· Hand should sit flat against dial with no gaps

Verify Clearance:

· Hour hand should clear dial markers by 0.2-0.5mm

· Should not touch date window frame

2.3 - Install Minute Hand

· Pick up minute hand with tweezers

· Align with minute wheel post (middle-length post)

· Lower vertically onto post

· Apply even pressure with hand setting tool

· Goal: Minute hand sits above hour hand with minimal clearance (but no touching)

Verify Clearance:

· Minute hand clears hour hand by ~0.2mm minimum

· Can rotate freely without touching hour hand or dial

2.4 - Install Second Hand

· Second hand is the most delicate (very thin tube)

· Use tweezzer with extreme care—tube collapses easily

· Align with seconds post (tallest, thinnest post)

· Press gently until seated

Critical Check:

· Second hand clears minute hand by ~0.3mm

· Tip of second hand doesn't touch chapter ring or crystal

2.5 - Test Hand Movement

· Gently turn crown to advance time

· Observe all hands moving smoothly without touching

· Check at 12:00, 3:00, 6:00, 9:00 positions

· Advance date through several days—verify hour hand doesn't interfere with date wheel

Common Hand Installation Mistakes:

· ❌ Hands touching each other (ticking stops intermittently)

· ❌ Bent hands (from uneven pressing)

· ❌ Second hand dragging on dial (pressed too low)

· ❌ Minute hand rubbing on hour hand

Professional Trick:

If hands are touching: Remove and reinstall. Never "bend to fit"—this creates permanent problems.

Verification:

· All three hands rotate freely without contact ✅

· Hands align properly at 12:00:00 position ✅

· Date changes cleanly between 11:45 PM - 12:15 AM ✅

· Second hand tip doesn't touch dial or markers ✅

Step 3: Install Movement into Case (15-20 minutes)

Detailed Instructions:

3.1 - Prepare Case

· Remove any protective plastic films from case interior

· Inspect case for debris, metal shavings, dust

· Use dust blower to clean interior

3.2 - Install Movement Spacer Ring (if required)

· Some cases require a plastic or metal spacer ring around movement

· Ring sits in case, movement drops into ring

· Verify ring is seated evenly

3.3 - Position Movement

· Hold case with dial side down

· Lower movement+dial assembly into case

· Align crown/stem with case crown tube opening

· Critical: Stem must slide smoothly into crown tube—don't force

3.4 - Verify Stem Alignment

· Movement should drop into case naturally

· Stem exits case at proper angle

· Movement sits level in case (not tilted)

3.5 - Secure Movement (Case-Dependent Method)

Method A: Movement Ring

· Install movement ring around dial edge

· Ring compresses against dial and case, holding movement secure

Method B: Case Clamps

· Some cases have small clamps/tabs that fold over movement edge

· Gently bend tabs to secure movement

3.6 - Test Crown Functions

· Attach crown temporarily (don't screw fully)

· Test pull positions:

· Position 0 (pushed in): Normal wearing position

· Position 1 (first click): Date change

· Position 2 (fully pulled): Time setting

· Verify smooth operation in all positions

Common Mistakes:

· ❌ Bent stem from forcing into crown tube

· ❌ Movement sitting crooked in case

· ❌ Debris trapped between movement and case

Verification:

· Movement sits level and secure ✅

· Crown operates smoothly in all positions ✅

· Dial is centered in case (view from front) ✅

Step 4: Install Chapter Ring (If Using) (5-10 minutes)

Detailed Instructions:

4.1 - Clean Chapter Ring

· Use Rodico to remove any fingerprints or dust

· Verify minute markings align properly with indices

4.2 - Align Chapter Ring

· Position ring so 12:00 marker aligns with dial 12:00

· Ring should sit flat on dial without gaps

· Verify minute markers align with dial hour markers

4.3 - Secure (Usually Friction-Fit)

· Most chapter rings are held by crystal pressure

· Some have adhesive backing—remove protective layer and press down

· Ensure ring doesn't shift during installation

Verification:

· Markers align perfectly at 12, 3, 6, 9 positions ✅

· Ring sits flat with no tilting ✅

Step 5: Install Crystal (15-25 minutes)

Crystal installation requires precision—cracking a sapphire crystal ruins a $30-50 part.

Detailed Instructions:

5.1 - Prepare Crystal

· Remove protective stickers/films

· Clean both sides with microfiber cloth

· Inspect for scratches or defects

· Apply dust blower to both sides

5.2 - Install Crystal Gasket

· Place gasket in case crystal groove

· Verify gasket is seated evenly (not twisted or bunched)

· Critical: Gasket provides water resistance—must be perfect

5.3 - Position Crystal

· Identify top of crystal (AR coating side goes outside)

· Place crystal on top of case, centered

· Dome crystals: Dome side faces outward

· Flat crystals: AR coating side faces outward

5.4 - Use Crystal Press

· Select die size matching crystal diameter

· Place case on crystal press base (dial side down)

· Position upper die centered on crystal

· Apply slow, steady pressure

· Listen for: Soft "pop" sound indicates crystal seated in gasket

5.5 - Verify Installation

· Crystal should be flush with case bezel

· No gaps between crystal edge and case

· Rotate case and inspect from all angles

· Look through crystal—verify no dust entered during installation

Alternative Method (No Crystal Press):

· Use flat, soft surface (folded towel on hard table)

· Place case dial-up

· Put crystal on top

· Cover with thin cloth

· Apply even pressure with flat object (wooden block)

· Press firmly until crystal seats

Warning: Hand-press method has higher dust contamination risk.

Common Mistakes:

· ❌ Cracked crystal from uneven pressure

· ❌ Dust trapped under crystal

· ❌ Gasket pinched or twisted (causes leaks)

· ❌ AR coating installed facing inward (reduces effectiveness)

Verification:

· Crystal flush with case ✅

· No gaps or tilting ✅

· No dust visible under crystal ✅

· AR coating on exterior (test: reflects less light) ✅

Step 6: Install Bezel and Insert (10-15 minutes)

Detailed Instructions:

6.1 - Clean Bezel and Insert

· Remove protective films

· Clean with microfiber cloth

· Use Rodico to pick up any dust from insert

6.2 - Install Insert into Bezel

· Apply small amount of adhesive (if insert isn't pre-glued)

· Use watch crystal cement or G-S Hypo Cement (thin layer)

· Press insert into bezel evenly

· Align 12:00 triangle with bezel 12:00 position

· Wipe away excess glue with cotton swab

6.3 - Install Bezel Assembly onto Case

Friction-Fit Bezels:

· Align bezel with case

· Press down evenly around entire circumference

· Bezel should snap into place

· Test rotation—should click smoothly (120 clicks for standard unidirectional)

Glued Bezels:

· Some bezels are secured with case back pressure

· Install after case back assembly

6.4 - Verify Alignment

· 12:00 bezel marker should align perfectly with dial 12:00

· Rotate bezel through full rotation—verify smooth action

· Check for wobble or misalignment

Common Mistakes:

· ❌ Misaligned insert (12 o'clock doesn't match dial)

· ❌ Too much glue (oozes out, looks unprofessional)

· ❌ Bezel not fully seated (wobbles)

Verification:

· Insert aligned with dial ✅

· Bezel rotates smoothly (unidirectional only rotates counter-clockwise) ✅

· No wobble or gaps ✅

Step 7: Install Crown and Test (10-15 minutes)

Detailed Instructions:

7.1 - Prepare Crown

· Verify crown gasket is installed inside crown

· Crown tube should be clean and free of debris

7.2 - Thread Crown onto Stem

· Align crown with stem

· For screw-down crowns: Thread clockwise gently

· Critical: Do not cross-thread—should turn smoothly

7.3 - Tighten Crown

· Screw down until snug (screw-down style)

· Don't over-tighten (damages gasket and threads)

7.4 - Test Crown Functions

· Position 0: Hand-wind movement (turn clockwise 20-30 times)

· Position 1: Change date (turn counter-clockwise)

· Position 2: Set time

· Verify all positions work smoothly

7.5 - Set Correct Time

· Pull crown to position 2

· Set time to current time

· Push crown back to position 0 (screw down if applicable)

Verification:

· Crown operates smoothly in all positions ✅

· No resistance or grinding ✅

· Crown flush with case (when screwed down) ✅

Step 8: Install Case Back and Pressure Test (15-20 minutes)

Detailed Instructions:

8.1 - Install Case Back Gasket

· Place fresh gasket in case back groove

· Verify gasket is seated evenly (critical for water resistance)

· Lightly lubricate gasket with silicone grease (optional, improves seal)

8.2 - Align Case Back

· Position case back over case opening

· For screw-down: Align threads

· For snap-back: Align any orientation notches

8.3 - Secure Case Back

Screw-Down Case Backs:

· Use case back wrench or friction ball

· Turn clockwise until snug

· Don't over-tighten: Damages threads and gasket

· Should be firm but not requiring excessive force

Snap-Back Case Backs:

· Position case back on case

· Use case press or flat surface method

· Apply even pressure around edges

· Listen for "click" when fully seated

8.4 - Verify Seal

· Case back should be flush with case

· No gaps visible

· For screw-down: Should be tight but not stripped

8.5 - Pressure Testing (Highly Recommended)

Professional Testing:

· Take to watchmaker with pressure tester ($20-30)

· Request test to rated depth (100m, 200m, etc.)

DIY Vacuum Test:

· Use vacuum tester ($15-50)

· Place watch in tester

· Create vacuum

· Monitor for pressure loss (indicates leak)

Water Test (Not Recommended for First Build):

· Submerge in water only if professionally pressure tested

· Water damage is irreversible if seals fail

Common Mistakes:

· ❌ Over-tightening case back (cracks case or strips threads)

· ❌ Missing or twisted gasket (instant water damage)

· ❌ Debris on gasket surface (breaks seal)

· ❌ Skipping pressure test (discover leaks the hard way)

Verification:

· Case back flush and secure ✅

· No gaps or misalignment ✅

· Passed pressure test (if tested) ✅

Post-Assembly: Final Steps

1. Install Strap or Bracelet

· Use spring bar tool to install spring bars

· Attach strap/bracelet of choice

· Verify spring bars are fully seated in case lugs

2. Wind and Set Your Watch

· Hand-wind 30-40 full rotations (clockwise)

· Set accurate time

· Wear for 8-10 hours to fully wind automatic movement

3. Timing Test

· Note time accuracy over 24 hours

· NH35/NH38 rated ±20 seconds/day

· Can be regulated by watchmaker if significantly off

4. Enjoy Your Custom Creation!

· Take photos of your build

· Share in modding communities (Reddit r/SeikoMods, WatchUSeek)

· Log your build specs for future reference

Common Mistakes & How to Avoid Them

Mistake #1: Hands Touching Each Other or Dial

Symptoms:

· Watch stops intermittently

· Second hand catches on minute hand

· Hands don't move smoothly

Causes:

· Hands pressed too low

· Hands not aligned properly during installation

· Wrong hand sizes for movement

Fix:

· Remove hands and reinstall with proper clearance

· Use hand setting tool for even pressure

· Verify hand specifications before purchase

Prevention:

· Test hand movement at all positions before installing crystal

· Press hands straight down (not at angle)

Mistake #2: Crystal Cracked During Installation

Symptoms:

· Visible crack in crystal

· Crystal shatters during pressing

Causes:

· Uneven pressure during installation

· Wrong die size on crystal press

· Forcing crystal into undersized case

Fix:

· Replace crystal (no repair possible)

· Verify case/crystal size compatibility

Prevention:

· Use correct die size

· Apply slow, steady pressure

· Double-check crystal diameter matches case specs

Mistake #3: Water Damage (Failed Seals)

Symptoms:

· Condensation under crystal

· Movement corrosion

· Dial water stains

Causes:

· Missing or damaged gaskets

· Case back not properly tightened

· Crown not screwed down

Fix:

· Immediately open case and dry all components

· Replace movement if corrosion present

· Replace all gaskets

· Professional pressure test before wearing

Prevention:

· Always use fresh gaskets

· Pressure test before water exposure

· Verify crown is screwed down before swimming

Mistake #4: Misaligned Date Window

Symptoms:

· Date appears half-hidden

· Date window shows parts of two numbers

Causes:

· Dial feet not properly seated

· Wrong dial for movement type

· Movement loose in case

Fix:

· Remove dial and reinstall

· Verify dial feet position matches movement

· Secure movement properly in case

Prevention:

· Confirm dial compatibility before purchase (NH35 vs NH38)

· Verify dial feet position (3:00 and 9:00)

Mistake #5: Dial or Hand Dust Contamination

Symptoms:

· Visible dust specs on dial

· Debris under crystal

· Lint on hands

Causes:

· Dirty workspace

· Not using dust blower

· Touching parts with bare hands

Fix:

· Disassemble and clean dial/hands with Rodico

· Use dust blower before reassembly

· Work in cleaner environment

Prevention:

· Work on clean microfiber cloth

· Use Rodico frequently

· Don't open all parts simultaneously

· Blow dust before installing crystal

DIY vs. Professional Modding Service: Which Is Right for You?

Choose DIY If You:

✅ Want to learn watchmaking skills

· Hands-on experience with mechanical movements

· Understanding of watch anatomy

· Problem-solving and fine motor skill development

✅ Enjoy the building process

· Satisfaction of creating something yourself

· Personal connection to finished piece

· Ability to modify/upgrade later

✅ Have time and patience

· First build: 3-6 hours

· Learning curve for techniques

· Possible mistakes requiring part replacement

✅ Plan to build multiple watches

· Tool investment spreads across projects

· Skills improve with each build

· Community engagement (sharing builds, learning from others)

DIY Budget:

· Tools (one-time): $150-$350

· Parts per build: $200-$600

· Total first build: $350-$950

· Subsequent builds: $200-$600 (tools already owned)

Choose Professional Modding Service If You:

✅ Want guaranteed quality

· Professional assembly techniques

· Pressure tested water resistance

· Warranty coverage

✅ Don't have time to learn

· Receive finished watch in 2-4 weeks

· No learning curve required

· Skip potential mistakes

✅ Only want one custom watch

· Tool investment not worthwhile for single build

· Professional finishes included

✅ Need water resistance guarantee

· Professional pressure testing equipment

· Proper gasket installation

· Tested to rated depth (100m, 200m)

Professional Service Budget:

· Basic builds: $400-$800

· Premium builds: $800-$1,500

· Includes all parts, labor, testing, warranty

Hybrid Approach: Best of Both Worlds

Many enthusiasts use a combination:

· DIY: Dial, hands, bezel, insert installation (lower risk)

· Professional: Pressure testing, regulation, water resistance work

This approach lets you enjoy the creative process while ensuring professional quality for critical functions.

Professional Seiko Mod Builds: SKYRIM WRIST

If you prefer professionally built custom Seiko mods with guaranteed quality and water resistance, SKYRIM WRIST offers expert modding services from our Nashua, New Hampshire studio.

What We Offer:

· ✅ Custom builds to your exact specifications

· ✅ Professional pressure testing (100m-200m certified)

· ✅ Genuine NH35/NH38 movements

· ✅ Premium parts (sapphire crystals, ceramic bezels)

· ✅ Quality control and warranty

· ✅ In-person consultations available

Whether you're building your first mod or your tenth, we're here to help with parts sourcing, technical advice, or complete custom builds.

Conclusion: Start Your Seiko Modding Journey

Learning how to mod a Seiko watch opens up a world of customization possibilities. While the process requires patience and attention to detail, the reward of wearing a truly unique timepiece that you built yourself is unmatched.

Key Takeaways:

· ✅ Start with quality tools—they last for many builds

· ✅ Take your time with hand installation (most critical step)

· ✅ Always pressure test before water exposure

· ✅ Don't be afraid of mistakes—they're part of learning

· ✅ Join modding communities for support and inspiration

Your Next Steps:

7. Gather your tools – Invest in quality basics

8. Source your parts – Plan your build design

9. Follow this tutorial step-by-step – Take your time

10. Test thoroughly – Verify all functions work

11. Share your build – Join the modding community

Happy modding!

Frequently Asked Questions

How long does it take to mod a Seiko watch?

First build: 3-6 hours (includes learning curve, careful checking)

Experienced modders: 1-2 hours for standard builds

Complex builds (GMT, chronograph): 4-8 hours even with experience

Can I mod any Seiko watch?

Technically yes, but Seiko 5 and SKX models are easiest due to standardized dimensions and abundant aftermarket parts. Modding Grand Seiko or Presage models is possible but requires custom parts.

Will modding void my Seiko warranty?

Yes. Any modification to a watch voids manufacturer warranty. However, most modders use new movements, not donor watches, so warranty isn't a factor.

How much does it cost to mod a Seiko watch?

DIY (first build): $350-$950 (includes tools)

DIY (subsequent builds): $200-$600 (parts only)

Professional service: $400-$1,500 depending on parts quality

Is it hard to mod a Seiko watch?

Difficulty level: Intermediate. The process requires patience and steady hands but no prior watchmaking experience. Hand installation is the most challenging step. With careful attention to this tutorial, beginners can successfully complete builds.

Where can I buy Seiko mod parts?

USA Sources:

· Namoki Mods

· Crystaltimes

· DLW Watches

· Lucius Atelier

International:

· AliExpress (budget)

· Tokeilab (Japan premium)

Full custom builds: SKYRIM WRIST 

What's the best Seiko movement for modding?

NH35A – Most popular, includes date function, widely compatible

NH38 – Best for no-date builds (cleaner dial aesthetic)

NH36 – Identical to NH35 (different designation)

All three offer same reliability, accuracy (±20 sec/day), and 41-hour power reserve.