[Demo notebook] Workbench questions: what to record before asking for service · RWI-27091

Case 23 — Maintenance question: how do I tell if an automatic actually needs service?

A sudden rate change has several possible causes. Ask a watchmaker to test suspected magnetism rather than diagnosing it from a compass or attempting an adjustment based on forum replies.

Case 23 — Maintenance question: how do I tell if an automatic actually needs service?

Keep a baseline log, describe changes in rate or running time and stop forcing rough winding. Follow the manufacturer’s guidance and arrange professional assessment when operation changes. A forum cannot prescribe a universal service interval.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

My bracelet is either slightly too tight or slightly loose with any link combination. The clasp has three micro-adjust holes, and there are no half-links. What are the options before I give up and go to a strap?

Exercise RWI-27091/24: address this question within its stated limits.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

Micro-adjust spacing varies by clasp. Measure the actual change at each setting rather than assuming a standard number of millimetres; compare the usable range with the link length.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

First, a clarifying question: how many links are on each side of the clasp right now? Fit often improves by moving one link from the 6 o'clock side to the 12 o'clock side, or the reverse. That doesn't change length, but it shifts where the clasp sits under the wrist, and a centred clasp feels less tight.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

Wrist size changes during the day and with temperature, sometimes by several millimetres. A fit that feels tight in the afternoon may be right in the morning. Before buying parts, check the fit at different times. You may find the 'too tight' setting is only a problem a few hours a day.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

Check whether a compatible half-link exists for the exact bracelet reference. Compatibility involves the connection and hardware, not just width. Ask a watchmaker if the correct part is uncertain.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

Resolution checklist. 1) Rebalance links around the clasp. 2) Test every micro-adjust hole with each link count. 3) Check fit morning and afternoon. 4) Look for half-links by bracelet reference. 5) Accept slightly loose if the head is light. If none of that works, a strap with finer hole spacing is a reasonable conclusion, not a failure.

Case 24 — Bracelet fit: half-links, micro-adjust holes and the 'between sizes' problem

A correction to a common assumption: a slightly loose fit isn't automatically wrong. Heavier heads tend to slide on loose bracelets, but a lighter watch often wears comfortably with a finger's width of space. Try 'loose' for a full day before deciding it doesn't work. Comfort over hours tells you more than the first minute.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

Lug width is the essential one: the inside distance between the lugs where the strap fits. Measure with a ruler marked in millimetres, ideally reading it under magnification. Most watches use even numbers (18, 20, 22mm), but odd widths exist. If you measure 19 or 21, measure again and check the manufacturer spec before ordering.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

I want to buy aftermarket straps but keep seeing 20/16, 22mm, 4mm thick and spring bar sizes. Which measurements do I actually need to take from my watch, and how do I measure them without the right tools?

Exercise RWI-27091/25: address this question within its stated limits.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

A notation like 20/16 means 20mm at the lugs, tapering to 16mm at the buckle. Taper affects look and comfort more than fit. A strong taper suits smaller and dressier cases, a straight strap suits sport watches. Your buckle or clasp also has to match the narrow end, so check that if you want to reuse an existing buckle.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

Thickness matters more than people expect. Straps around 4 to 5mm at the lugs can hit the case or stop the strap folding down on watches with short lugs or tight lug-to-case clearance. Do you know whether your watch has drilled lugs or a tight gap between strap and case? That tells you how much thickness is safe.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

Document spring-bar diameter, end-tip fit and the strap’s clearance using appropriate measuring tools. If dimensions or compatibility are uncertain, ask a watchmaker rather than forcing a bar or substituting an unsuitable part.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

Correction to a common shortcut: don't measure lug width on an existing strap. Leather and rubber straps compress or swell, and some are made slightly undersized on purpose. Always measure between the lugs themselves, with the strap removed if possible.

Case 25 — Strap dimensions: lug width, taper, thickness and spring bar diameter explained

Summary order of importance. 1) Lug width, measured between the lugs. 2) Lug-end thickness against clearance. 3) Spring bar diameter. 4) Taper and buckle width. 5) Length, which is usually given as long side / short side in mm and should be compared with a strap that already fits you.

Case 26 — Disputed observation: is this dial colour shift real or just lighting?

Several posts claim the newer batch of a particular blue-dial model looks more purple than the earlier batch. Others say it's purely photography and white balance. Can we settle this with evidence instead of arguing from different photos?

Exercise RWI-27091/26: address this question within its stated limits.

Case 26 — Disputed observation: is this dial colour shift real or just lighting?

The difficulty is that phone cameras adjust white balance automatically, and blue dials are especially sensitive. Two photos of the same dial under different light can easily look like a 'batch difference'. Any comparison needs both dials in the same frame, under the same light, ideally next to a neutral grey or white reference card.

Case 26 — Disputed observation: is this dial colour shift real or just lighting?

Clarifying question: does anyone in the thread have access to both versions at once? Without simultaneous comparison, every claim either way is weak evidence. If not, the next best option is photos with a grey card in frame and white balance locked or set manually, which at least makes separate photos roughly comparable.

Case 26 — Disputed observation: is this dial colour shift real or just lighting?

Suggested protocol. 1) Both dials in one frame. 2) Diffuse daylight, no direct sun, plus a second shot under neutral indoor light. 3) Grey card visible. 4) No filters, no editing. 5) State camera settings if known. If both shots show the same direction of difference, the claim is supported. If the difference flips between lighting conditions, it's most likely lighting.