Casio MW-240 (module 1330) is a slightly oversized, minimalistic, high contrast easy reader quartz which looks nice and can be ordered online for a mere 16 Euros. Its dedicated resin bracelet fits the 16mm lug width.
This mod is about widening the space between lugs to accomodate any common 18mm bracelet, NATO, Zulu or other one-piece nylon strap. Note: This Casio is brand new so its 2-year full warranty is now void.
Lugs are manually filed down using two grades of round and rectangle needle files. Originally I've planned to use Dremel tool but decided not to since there was a huge probability of messing up the case if the attachment slips. Lugs are inevitably thinned (=weakened) in the process, so their inward surfaces were intentionally filleted and fillets carefully rounded with 600 grit carbide paper to reduce stress concentration and - hopefully - prevent them from breaking (see image below).
Since original lug holes were removed with the excess material, new ones had to be fabricated using the state-of-the-art propane burner & paperclip technique. 17mm spring bars are used here to reduce outward pressure on the lugs, and so far they are holding OK.
Next time I'm going to sand a milimeter or two off the crown guard (shoulder) since crown is too recessed by design and it's quite difficult to pull it out with an average fingernail. This of course requires removing the case back and stem...
New OD Zulu strap with black hardware:
New OD Zulu strap with black hardware:
