Orient's In-House Movements Explained

“In-house” is one of the most stretched phrases in watchmaking. It can mean a movement designed and built from raw material by the brand, or it can mean a bought-in base with a new rotor and a new name. Orient sits near the first end of that range, and the story of how it got there runs through a town in northern Japan.

From Hino to Akita

Orient’s modern history begins in Hino, Tokyo, where a prewar watch factory that had shut down after the war was re-founded as Tama Keiki Co. in July 1950. It was renamed Orient Watch Co. in 1951, and the same year it launched Orient Star, the line that was meant to deliver its best mechanical watches at moderate prices.

The movements that matter today come from further north. Orient established a subsidiary in Akita Prefecture called Akita Orient Precision Instruments, which now belongs to Seiko Epson under the name Akita Epson. It sits in Yuzawa, and it also makes inkjet print heads. Epson says Orient Star skeleton models are hand assembled in Akita.

What in-house means here

For Orient, in-house means the calibers belong to its own Cal. 46 family, developed by Orient and now by Epson, and are manufactured by Epson’s own subsidiary before being cased in watches sold under Epson’s Orient brand. They are not modified versions of a Swiss or third-party base.

It does not necessarily mean every last component is made under one roof. Epson’s technical pages and Orient’s materials describe design, the silicon escape wheel and assembly. We have not found a source that lists which smaller parts are made by Akita Epson and which come from elsewhere in the Epson group, so we will not claim more than that.

An Orient Star automatic photographed in black and white — An Orient Star automatic, photographed in black and white. Photo: Oka / Unsplash

The old guard: 46943 and 48743

Epson dates the Cal. 46 family to 1971. It was designed to be smaller and thinner than Orient’s earlier L-type movements and used a Magic Lever in its self-winding system, and the family went on to power much of the catalog for decades.

The best known member is the 46943, which Orient Watch USA says powered the first Mako, the EM65, in 2004. It was a 21-jewel automatic at 21,600 vph with about 40 hours of reserve, and it neither hacked nor hand-wound. Worn & Wound noted that setting the day needed a separate pusher at 2 o’clock, the second crown in what Orient Watch USA calls the Mako’s signature dual-crown setup.

The 48743 inside the early Bambino was in the same mold. Worn & Wound’s 2012 review describes it as a 21-jewel automatic at 21,600 vph with 40 hours of reserve, with a date but without hacking or hand-winding. These were simple, reliable movements, but they did not give the wearer much control.

The F6 generation: F6922 and F6724

Epson says engineers began developing the 46-F6 generation around 2012, with the aim of standardizing base plates and bridges across the range. The F6922 appeared in 2016, in the Mako II and Ray II, and it fixed the two things the 46943 lacked.

The F6922 has 22 jewels, beats at 21,600 vph and runs for about 40 hours. It hacks and hand-winds, and it shows the day and date. Orient Watch USA notes that the upgrade also removed the Mako’s second crown. Today the F6922 is in the Kamasu, the Mako-3 and the AA02 Diver.

The F6724 is its date-only counterpart, with the same 22 jewels, beat rate, reserve, hacking and hand-winding. It went into the second-generation Bambino around 2016 and remains there, in the 38.4mm Version 7 and the 40.5mm models. Orient rates both calibers at +25/−15 seconds a day. For 2026 Orient has also introduced the F6524, in the new Bambino No Date.

Orient Star: F6F44, F7F44, F6R42 and F6N47

Orient Star’s movements build on the same family with more functions and more reserve. A power reserve indicator, which Epson says it developed in the 1990s, is now a standard Orient Star feature.

F6F44. 24 jewels, 21,600 vph, 50 hours, with a power reserve indicator and small seconds. As an F6 caliber, it falls under the +25/−15 seconds a day that Epson gives for that generation.
F6R42. 22 jewels and 50 hours, with a power reserve indicator plus an open-heart aperture over the balance. It powers the Orient Star Classic Semi Skeleton, $450 at Orient Watch USA.
F6N47. The 50-hour caliber in Orient Star’s M42 Diver line. The Orient Star Sports Diver RE-AU0301B00B uses it, and is a 200m diver rated to ISO 6425.
F7F44. Epson dates the 46-F7 generation to 2017, and its headline change was accuracy, with the rating tightened to +15/−5 seconds a day. The F7F44 keeps a 50-hour reserve and a power reserve indicator.

That last figure is worth pausing on. A 20-second window, skewed toward gaining time, is a meaningful step up from the 40-second window of the F6 calibers, and it is a rating Orient publishes rather than a hope.

The F8 calibers and the silicon escape wheel

The 46-F8 generation is where Orient’s engineering gets genuinely interesting. Its escape wheel, the part that releases the mainspring’s energy to the balance in steady steps, is made of silicon rather than metal.

Epson says it used MEMS processing from its semiconductor work to make the part, raising machining accuracy from a hundredth of a millimeter in metal to a thousandth in silicon, and that the switch cut the wheel’s weight by about a third. SJX, analyzing Seiko Epson’s patents in February 2026, put the saving against a nickel silver wheel at about 65 percent and reported that it increases the energy reaching the balance by about 30 percent. The sources differ on the weight figure, but agree on the direction. SJX also notes the wheel is held to its pinion by flexible arms rather than adhesive.

The first F8 calibers were the hand-wound F8B62 and F8B63, launched in 2021 for Orient Star’s 70th anniversary skeleton. They are rated at +15/−5 seconds a day with a 70-hour reserve, 20 hours more than the F7. The silicon wheel is blue, and it is visible in the skeletonized movement.

In February 2024 the F8N64 followed in the M34 F8 Date, also with a silicon escape wheel, rated at +15/−5 seconds a day with 60 hours of reserve.

The F8 calibers show what Orient’s in-house capability is really for. Not prestige, but the ability to change a part and gain 20 hours.

What this means for the person buying the watch

On the cheapest Orients, in-house ownership shows up as the basics done properly. Hacking, hand-winding and a +25/−15 rating come standard under $300, a price where none of those can be taken for granted.

At Orient Star prices it shows up as features normally found higher up the market, among them power reserve indicators, a +15/−5 rating and now silicon. The finishing is functional rather than decorative, and nobody will confuse these movements with Swiss haute horlogerie. That is not their job.