Which watch oil goes where?

Each lubricant in a watch goes where its thickness matches the speed and the load of the part it sits on, and the movement maker's technical document says which is which. For the ETA 2824-2, the answer is 9010 for the fast end of the train and the balance, HP-1300 for the slow, heavily loaded end, 9415 on the pallet stones, and 9504 grease in the keyless works. The rest of this page shows where ETA puts each one, what the data sheets say about them, and the two substitutions that cause most of the confusion.

Two answers circulate. One says 9010 does the whole escapement, and a large US supplier's listing calls 9010 "ideal for pallet jewels, escapements, and balance staffs". ETA's current document says otherwise for the pallet stones: it names a separate "special oil for pallet stones", 9415. The listing is not wrong about pivots. It is wrong for the one place where the escape wheel teeth slide across the stones, and that is where the escape wheel delivers the impulse that keeps the balance at its amplitude.

The lubricants and their numbers

Moebius, the Swiss maker whose products ETA and Seiko Instruments name in their documents, publishes the figures below. They come from the product data that two of the large trade suppliers, Boley in Germany and Esslinger in the US, carry for each product. Viscosity is in centistokes (cSt); the higher the number, the thicker the oil.

The two numbers that matter most are the first and the fourth. HP-1300 is more than eight times as thick as 9010, and that ratio is the whole logic of a lubrication chart. A balance in a 28,800 vph movement swings eight times a second on pivots that carry almost no load, and a thick oil would brake it. The barrel turns slowly under the full pull of the mainspring, and a thin oil would be squeezed out of the bearing.

9415 is the odd one in the table because it is a grease that behaves like an oil. Boley describes it as thixotropic: it flows like oil while the parts are moving and returns to its solid form at rest, so it stays on the pallet stones instead of spreading. Boley's listings write the beat-rate boundary as "21600 Hz", which is the same figure in vibrations per hour; no watch escapement runs at 21,600 Hz.

Where ETA puts each one on a 2824-2

ETA's technical communication for the 2824-2 (version 25, dated 6 October 2022) gives a lubrication legend on each assembly stage. The parts in each stage and the lubricants that stage's legend names are:

The exact dots are on the drawings, so this table tells you which products a stage uses, not every point that gets one. Three instructions in the text are easy to miss.

• Epilame first. "After washing and before reassembly, coat with the Moebius Fixodrop ES/BS 8981 epilame." ETA allows Fixodrop ES/WR-S 7061 and ES/WR-P 7071 as alternatives. The epilame is what keeps a drop of oil from creeping away from the point it was placed.
• Do not wash the automatic device. "If required, exchange for an original prelubricated part supplied by ETA SA." The reversing wheels are the 2824-2's classic weak point, and ETA's answer is a new part, not a re-oiled one.
• Work the date jumper. Lubricate the date jumper, turn the date indicator about 10 teeth with the quick correction, and repeat the pair until the jumper has been lubricated three times.

The Sellita SW200-1 follows the same architecture as the 2824-2, but its lubrication points are in Sellita's own technical document. Work from that, not from ETA's, for a Sellita.

The chart has changed, and older charts still circulate

ETA's own revision log for the 2824-2 shows lubrication changed or added in nine versions between March 2009 and September 2016. A chart printed from an older version, or copied from someone else's copy, may not match the current one. That is the main reason two watchmakers can each cite "the ETA chart" and disagree.

ETA's document for the smaller 2000-1 (version 05, 14 November 2008) shows what the older generation looked like:

• "Thick oil or grease: Moebius HP-1300 or Moebius D5", where the 2022 2824-2 document names HP-1300 alone.
• "Special oil for pallet stones: Moebius 941 or Moebius 9415", where the 2022 document names 9415 alone. Both are 28,800 vph movements.
• Grease Jismaa 124 in the hand-winding, setting, date and corrector stage, where the 2022 document names Moebius 9504.
• For one automatic part: "Only after washing, use very little oil Moebius 9010."

The D5 to HP-1300 change matters for anyone who wears a watch in the cold. The data sheets put D5, a blend of mineral and vegetable oils, at -5 to +80 °C with a pour point of -10 °C, and HP-1300, a synthetic, at -35 to +100 °C with a pour point of -41 °C. The cold weather answer covers how a thickened lubricant shows up in the rate. D5 also carries a shelf life of three years against six for 9010, which is a reason to date the bottles on the bench.

941 or 9415: the beat rate decides

For the pallet stones the rule is simple once the beat rate is known. Boley's Moebius listing puts 941 on "escapements < 21600 ('slow oscillators')" and 9415 on escapements from 21,600 upward ("fast oscillators"). In practice:

• 18,000 vph and slower: 941.
• 21,600 vph (the Seiko NH35 and NH36): 9415 by Moebius's boundary.
• 28,800 vph (ETA 2824-2 and 2892A2, Sellita SW200-1 and SW300-1, Miyota 9015): 9415.

Boley's application note for 9415 gives a quantity as well as a place: on a clean movement still under warranty, a single drop on the first pallet stone. If the beat rate is not printed on the movement, a timegrapher reads it, and our lift angle chart gives the beat rate of the common calibers alongside the angle. The guide to escapements shows where the stones meet the escape wheel and why that contact needs its own product.

Seiko and other Japanese movements

Seiko Instruments' parts catalogue for the NH3 series (version 04) names Moebius 9010 in its oiling legend and marks each point with a quantity: "normal quantity" or "sufficient quantity". It is the same 21,600 vph, 53 degree lift angle movement described on our Seiko NH35 page. The tables of Moebius substitutes for Seiko-branded oils that circulate on repair forums do not come from a Seiko document we could read, and we have not used them here.

The barrel and the mainspring

ETA supplies the 2824-2 barrel as a "movement barrel complete", which is why its document carries no mainspring lubricant: the barrel is replaced, not opened. When a barrel is opened, the data sheets divide the job. 8200, a semi-fluid grease that is solid at 40 °C, is listed for mainsprings. 8217 is a braking grease for automatic barrels, where the end of the spring, the bridle, slips against the barrel wall once the spring is fully wound. Boley's data says it gives "the necessary adhesion and the perfect sliding-braking effect of the bridle against the barrel wall". Our answer on overwinding an automatic explains why the bridle is there.

What this means if you are paying for a service

A service is mostly this chart applied correctly. Ask which document the watchmaker works from and whether the automatic parts are replaced or re-oiled. A stable amplitude after a service is the evidence that it went right; our guide to timing your own watch shows how to check it. The servicing guide describes the rest of the work, and the answers on how often to service and what a service costs cover timing and price.

When this answer stops applying

• In-house movements. Everything above comes from ETA, Seiko Instruments and Moebius documents. A brand's own caliber follows the brand's own specification, and Moebius lists HP-1300 for co-axial escapements, a sign of how far the rules move away from the Swiss lever.
• Chronographs and complications. The 9504 data sheet lists chronograph mechanisms, but which points get it is in the maker's document for that caliber, not in the 2824-2 chart.
• Other ETA calibers. The stage table is for the 2824-2 at version 25. Every ETA caliber has its own technical communication, and the revision on the page is the one to follow.