Pocket watches are both delicate and durable at the same time, easily broken and yet built with quality materials to run for decades, and designed with maintenance and repair in mind.
Most collectors want the pieces in their collection as close to factory-original as possible, so here are a few of the more obvious issues to avoid when considering purchasing a watch.
Once a fragile porcelain dial is broken or cracked it cannot be reversed, and correct replacements take time to locate.
Incorrect or missing hands are an obvious problem because they can be difficult to find and expensive to replace.
Dents are always caused by an impact. The metal is now stretched, and the internal components have likely suffered too.
A bent or leaning pendant is an indicator of an impact, which likely means a broken balance staff. Bent pendants are also difficult to wind because the stem is binding in the arbor.
Hunter cases have delicate hinges and it doesn't take much to force the covers past 90 degrees. Once the metal of the frame is distorted it cannot be made right again.
Patterns that don't line up with the pendant can be caused by a manufacturing defect or the back is from a different case, resulting in mismatched serial numbers.
Crowns are one of the first things to wear out. Case manufacturers made many different models and sizes, so finding a matching new-old stock replacement is not easy.
The bezel is the thin ring that holds the crystal, and is specific to that brand of case. Finding an exact replacement can be nearly impossible - and you still need a crystal.
Chains wore the bow out very quickly, so most are unoriginal and not always the right style. Aftermarket replacements are available, but the color-match is seldom accurate.
Replacement balance or plate jewels are the single most common indicator of damage.
Ruined balance weights mean the factory poise is lost, affecting positional accuracy.
A hairspring is matched to the balance wheel, so replacing it means re-timing the watch.
Incorrect or mismatched screws usually mean that the original threads are stripped.
Broken or missing parts are a sign of sloppy work and are sometimes difficult to replace.
Ghost marks mean that the case has held previous movements and is not the original.
Parts inevitably get worn out, lost or broken over the years, which must be replaced from new-old stock or culled from donor movements. This is standard practice with small parts like screws and jewels, but the larger pieces, like the upper and lower plates, balance wheel, winding block and several others, are all factory-inscribed with matching serial numbers. A Frankenwatch is one that is cobbled together using any part with a serial number that came from a different watch.
Watches with matching serial numbers are far more desirable from a collecting standpoint, especially early or rare examples worth thousands of dollars. To a certain extent this is also true of watches that are still in their original cases, and the value can really climb when provenance is involved, such as a factory shipping box or bill of sale. In May of 2018 our friends at Jones & Horan Auctions sold Rockford SN #1 - an original combination - for $91,000. Click HERE to see it happen.
Collecting antique pocket watches is an excellent investment strategy, and buying the best example that you can afford is a better approach than going broke resurrecting a Frankenwatch. Avoid unethical sellers who gleefully part out intact, original examples and sell the components for profit, knowing there are plenty of novice collectors who will chase those bits and pieces.
Key winds are several decades older than railroad-era pocket watches, which means that they've had several more decades of repairs, and were sometimes run for far too long between cleanings. There was a transitional period in the 1880s when some models were equipped with both key and stem winding mechanisms, but by the turn of the century the square key had become obsolete.
Nearly all key winds are low-grade pieces with 15 jewels or less and were not designed to run forever, so anticipate worn bushings and gear train pivots. Mismatched hands and missing screws are common, and since most had only a single case screw they are usually loose inside the case.
The oldest key winds had solid balance wheels, which couldn't compensate for changes in temperature, and they had no weights, so there was no simple way of correcting for poise issues. The flat hairsprings had no overcoil and were mounted in an inaccessible spot underneath the balance wheel, and because of these reasons they were not the most accurate timekeepers.
It's difficult to find examples that aren't ruined, especially hunters with their broken lift springs, reamed-out key arbors and worn front cover latches. The movements usually have stripped screws, cracked jewels, mismatched serial numbers, distorted hairsprings, missing alignment pins, loose canon pinions, and quite a few other problems. The taper pins holding the dial were easily lost and replaced with anything handy, which enlarged the dial feet until they split.
Quality work takes patience, plenty of time and skill, the right tools, and sound methods.
Always send your heirloom timepiece to the best watchmaker that you can find.
Beware the low prices of those who service a watch in an hour because they're cutting corners, usually with very disappointing results. I see a lot of intentional damage on a daily basis, usually done by the same people who were paid to repair the watch in the first place.
I also spend considerable time reversing the "fixes" of those who like to tinker with their watches. Here's a gallery of some of the worst botched repairs and issues that weren't addressed.