[rollei_list] Re: OT: Bristol Wrenches
- From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
- To: <rollei_list@xxxxxxxxxxxxx>
- Date: Thu, 29 Jul 2010 12:48:05 -0700
----- Original Message -----
From: "Don Williams" <dwilli10@xxxxxxx>
To: <rollei_list@xxxxxxxxxxxxx>
Sent: Thursday, July 29, 2010 11:57 AM
Subject: [rollei_list] Re: OT: Bristol Wrenches
At 02:53 AM 7/29/2010, Richard wrote, in part:
Anyone who wants Bristol wrenches can get them from the
original
manufacturer and Xcelite makes a set of screwdriver style
Bristol
wrenches. I got my Bristol keys from Max Gain (do a Google
search)
and the Xcelite set from Test Equipment Depot (again a
Google search
will find them). The keys are cheap, the Xcelite set not
so cheap.
The reason for the exotic tools is that I am working on a
Collins
receiver and Collins was fond of Bristol screws. There are
at least
a dozen different odd screw caps these days. Most intended
for use
with power equipment. I think the reason Collins chose
Bristol is
because they are a lot less likely than Allen heads to be
damaged by
camming of the wrench. All too often one finds Allen set
screws
where the corners of the socket are so badly damaged that
the screw
has to be removed with an EZout.
--
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx
I surely agree with you about Allen and also Phillips. I
have often
had to grind or file them down to restore them to duty.
It's
interesting how most folks choose a smaller-than-required
Phillips
screw driver and thus damage the driver and the screw. (I
must be
one of them).
Also, I have forgotten the name, but what drive is similar
to
Phillips but a bit better, less camming, etc.?
DAW
The most common type is the Pozidrive. These look like
Philips but are shaped a bit differently with larger flat
surfaces. The Pozidrive was designed to eliminate caming and
allow the use of power operated screwdrivers in production
settings where air or electrically operated tools are
common. There are other cross-slot types such as Reed and
Prince but they have not become as well accepted as
Pozidrive. One problem is that while a plain Philips will
work on a Pozidrive screw it doesn't grip it very well.
The right size Philips screw driver will look too big
so people often use one that is too small. The right one
will fit the slot completely and have no play.
There are other types of socket head screws than Allen
and Bristol, star and other spline types are fairly common
although I think Allen heads are far more common than any of
them. Torx heads are a kind of socket head and are now
common for screws and bolts but I think not for set screws.
I have also found that German cameras have straight slot
screws with much narrower slots than common screws. One must
grind the screwdriver tip to work them. Smaller size drivers
that have thin enough tips will be too narrow to grip the
slot properly and will damage the screw. I think similar
screws are found in clocks and watches but common
"jeweller's" screwdrivers are too thick for them.
--
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx
---
Rollei List
- Post to rollei_list@xxxxxxxxxxxxx
- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe'
in the subject field OR by logging into www.freelists.org
- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with
'unsubscribe' in the subject field OR by logging into www.freelists.org
- Online, searchable archives are available at
//www.freelists.org/archives/rollei_list
Other related posts:
