27 Sep
2014
27 Sep
'14
1:54 p.m.
i would expect somebody working in a museum to have the right size
screwdriver for such work (specially ground if necessary).
Regular hardware store screwdrivers, and those found on swiss army
knives, are rotten tools because they are wedges. Proper screwdrivers are found in clockmaker/watchmaker and gunsmith supply
shops. I have
such a set that I use whenever I can, because it can?t slip out of the
slot. There?s a nice set available from Brownell?s in the USA, about 6
width at 4 thickness choices each.
THat sounds useufl. I'll bet it has a price to match, though (not that i
object ot paying money for good tools)
Especially when the tools in question are readily available for very
small sums of money ? it?s not as if you had to get them custom made.
(And of course, if you work on museum pieces, you DO have to be prepared
to get tools custom made if necessary!)
I have no idea id the square key tool is easy to get, I do know that any
machinist could make one in a few minutes on a millign machine. And
that's what I would do. This si not exactly complicated? 100 bits for $10 or so. Not strong at all but good
enough for
occasional use, and it included oddball stuff like triwing (like
Phillips but 3-fold symmetry instead of 4-fold). If you run into
There's also Torq (not Torx) which is like phillips but with the 'wings'
offset to as to bcontinuations of the sides of a cetral square. And
several others, of course.
I have a reasonable set of such bits made by Wera. The nice reather
(apart form the fact that they are good steel) ias that the bit shank is
quite long and a sutiabel diameter for the tip. So they will work on
screw down the bottom of deepish holes. THis set only cotnains one flat
screwdrifer, but the sides fof the tip are paralell, not a wedge. I wish
I could get more sizes of thsoe, perhaps I can if I look around..
Bristol spline (in 1950s electronics like the Collins
51-J) it gets a
little harder, but those too are still available at modest prices. And
Bristol spline also turn up in classic computers. I've come across them
in the Friden flaxowriter and in the monitor section of the IBM 5155
(portablePC). Thsoe tools are very hard to find in the UK. I've yet to
find a tool shop (as opposed to a wrb site, etc) that's even heard of them.
And yes, I don't use the wrong tool here either. Allen hex != Bristol
Spline != Torx. The butchers an use 3/32" allen kesy on classic macs.
I'll use the right tool.
as you point out, any tool you could possibly want is
easy to make with
a bit of machining.
In th case (pun intended) of the museum, the catcvhes took a square key
abotut 5/16" on a side, much larger than any Robertson tool. It looked as
thoguh the old 'carriage key [1]' migher have fitted it. In any case, it
would not be hard to make one.
[1] Used to opening bits of publc transprot vehicles, like trains and
buses. Like the cover behind the destination blind on a Routemaster (I
should not know this). The square seciton spidnle fro ma UK door handle
is about the same ziae (a little smaller), something that many schoolboys
discovers (and then caused problems as a result.
AS yet I don';t ahv a set of the 5-pointed torx-like tools, althoguh I
have found suppliers of them. Soemthign I've not seen for sale are
triangulr screwdries (or bits), although I have come across screws with a
triagualr recessin ion the head. That was one time I had to make a tool
to get something apart.
-tony