FOR FIXING SPECTACLES
all about screws and screwdrivers
of screws, types of screwdrivers, which screws fix spectacles, screws
for clocks and watches.
BUY NOW: CLICK ON A PICTURE
are some giant pictures showing you the selection of 1000 screws:
(large picture, please be patient while it loads!)
screwdrivers and screws
SCROLL DOWN SLIGHTLY FOR AN ARTICLE ABOUT TYPES
CLICK ON THE PICTURE
colours vary from a dark steel colour to a very light (but still steel-like
colour), we don't think any of them are made of brass. This photograph
makes them appear more 'gold' than they really are, pobably because of
the light reflecting off the orange container.
If you thought
there were only two types of screwdriver, flat (for slotted screw heads)
and cross-head (for Phillips and Pozidriv) - think again! There are ten
basic types of screw / screwdriver, and also a dozen different shapes
of screw head.
A good place to see pictures and descriptions of each is Wikipedia
- and you will also find a summary of the various screw-size-classification
systems (Whitworth, BA etc).
For a more technical explanation try the American engineering company
Engineering Parts Sourcing Inc:
screw point types, hole
metric conversions, screwdriver
sizes, or for the geometry of the screw thread try Western Australia's
of Mechanical Engineering.
screwdrivers (for slotted screw heads) are the
most common of all, especially for spectacles and watches. We sell specialist
small sets of screwdrivers for very tiny objects - if you want
larger screwdrivers go to your local DIY store.
watchmaking the thickness of the blade should fit the width of
the slot exactly. Since you can't buy screwdrivers in different thicknesses,
a watchmaker will re-grind the blades. Very 'sharp' blades in very 'wide"
slots are very difficult to handle.
Phillips screw has slightly rounded corners
and is designed so that the screwdriver will slip out ("cam out")
under turning-pressure ("torque"). This is to prevent over-tightening.
So when customers complain that our screwdrivers are no good because they
keep slipping out of the screw - they're meant to!
There are other varieties which do not cam out: the Reed and Prince and
the Frearson have 'sharp' crosses and, similarly, the Pozidriv has four
extra points which make it star-shaped. Another cross-shape that does
not cam out is a BNAE, a tiny screwdriver-head in the form of a 'bit'
for a power tool.
above are those used in clocks, watches and spectacles. There are many
CLOCK AND WATCH KEYS (WINDERS) AND HEXAGONAL (HEX)
clocks and watches don't have inbuilt winders (they hadn't been invented)
- you must wind these with a special
square key, and these come in dozens of sizes. In the world of screws
they are known as the Robertson design...but we don't actually sell the
'screwdrivers' because the 'screwdriver' (male) is fixed to the clock
or watch, and it is the 'screw' (female) that is the winder. We sell these
winders in all sizes, both for
clocks and for
A variation is a very long blunt screwdriver in the form of a six-pointed
star, known as the Torq, which also comes in a 5-pointed-star version
(5-part) - these fit many mobile phones.
all screwdrivers and screws.
ARTICLES (jewellery and horology)
(ringsizes, finger sizes, winders, weights)
(clock and watch key winders)
polishing and polishes
of jewellers pliers and cutters
tarnish from silver