Assemble Watches
What Parts Do I Need for a Seiko Mod?
A complete Seiko mod build requires: a case, movement (typically NH35 or NH36), dial, hands, bezel ring, bezel insert, crystal, caseback, and bracelet or strap. Each part has specific compatibility requirements with the others. Assemble Watches checks all of these as you plan your build.
- What is the minimum parts list for a Seiko mod?
- At minimum: case, movement (NH35 or NH36), dial, hands, bezel ring, bezel insert, crystal, and bracelet or strap. A caseback is typically included with the case. Tools needed separately: case back wrench, hand setting tool, Rodico putty.
- What movement should I use for a Seiko mod?
- The NH35 is the standard choice: it hacks, hand-winds, and has no date complication, making it compatible with a wider range of dials. The NH36 adds a day display alongside date — choose it if you want the day/date function and your dial supports it. Both share the same case footprint.
- What dial should I choose for an NH35 build?
- Choose a dial explicitly listed as NH35-compatible or SKX007-compatible. The dial feet positions must match the movement. Beyond compatibility, check the dial's date window alignment: NH35 has date at 3 o'clock, NH36 has day/date. Dial diameter is typically 28.5mm for SKX007/SRPD-based builds.
- What tools do I need for a Seiko mod?
- Essential tools: spring bar tool (strap and bracelet changes), case back wrench (screw-down casebacks), hand setting and removal tools (for dial and hand work), Rodico putty (dust and fingerprint removal). A crystal press is needed only for crystal swaps.
- Where can I check all my Seiko mod parts are compatible before buying?
- Use the Assemble Watches builder at assemble.watch/build. Select your case, movement, dial, hands, bezel, and bracelet — compatibility is checked automatically as you go, and you get a parts list with vendor links at the end.