TMI/Hattori SEIKO VD78 Movement Small Second Wheel

Product Description

The TMI/Seiko VD78 Movement Small Second Wheel is a genuine Japanese-made component for the popular VD78 quartz movement. The VD78 is a 10½ ligne (approx. 22.6mm) caliber with a slim 3.45mm height, featuring a small seconds subdial at the 6 o’clock position . As part of the gear train, the small second wheel drives the subdial seconds hand for accurate timekeeping . This genuine TMI/Seiko part is essential for watchmakers restoring proper small seconds function when the original component becomes worn or damaged.

Features & Function

• Genuine TMI/Seiko part – authentic Japanese-made component for the VD78 movement

• Small seconds drive – drives the 6 o’clock subdial seconds hand for accurate timekeeping

• Compact design – designed for slim 3.45mm quartz movements

• Essential for service – commonly replaced when small seconds hand operation becomes irregular

Specifications

• Compatible Movement: TMI/Seiko VD78

• Movement Size: 10½ ligne (approx. 22.6mm) 

• Movement Height: 3.45mm 

• Subdial Position: Small seconds at 6 o’clock 

• Hand Sizes: Hour: 1.20mm / Minute: 0.70mm / Small seconds: 0.20-0.21mm 

• Battery: 377 / SR626SW 

• Origin: Japan

Applications

• Service and repair – replacing worn or damaged small second wheels in VD78 movements

• Gear train restoration – ensuring smooth subdial seconds hand operation

• Suitable for professional watchmakers and experienced repair technicians

FAQs

1. Is this a genuine TMI/Seiko part?

Yes, this is a genuine Seiko (TMI) factory part made in Japan. The VD78 is a quartz movement manufactured by Time Module Inc. (TMI) and is widely used in Invicta, Ingersoll, and other watch brands .

2. What are the signs that the small second wheel needs replacement?

Common signs include small seconds hand not moving smoothly, stopping, or moving irregularly, or visible wear/damage during movement inspection. A qualified watchmaker can diagnose these issues.

3. Is professional installation required?

Yes, small second wheel replacement requires movement disassembly and specialized tools. We strongly recommend installation by a qualified watchmaker.

Why Choose SOFLY Watch Parts?

• Fast worldwide shipping within 3 business days.

• Competitive pricing on Seiko/Hattori calibers.

• 3,000+ watch movements and parts in stock.

• Trusted by watchmakers worldwide.

• Personalized sourcing support via [email protected] or WhatsApp +86 18620212114.