Dick, as others have said, these probably need Bristol wrenches. I bought
some a few months back from

Good luck,

Malcolm, W1/GW3NJY


"Dick" wrote in message
...
I'm trying to get a hold of a tool that will undo grub screws
securing the front panel knobs on my venerable BC221, can anyone suggest
where I can get a hold of one, a modern equivalent and/or something that
can be modified to do the job ??
Although all BC221s were provided with the tool (stored in a
clip beside the spare valves) I've never seen one and can only guess
that it must be something like a very small Phillips screwdriver head
but with a parallel rather than tapered tip. It must also be less than
3/32" dia 'cos I've just tried to make one by hand out of 3/32" dia
steel rod and that was too big, don't think my eyesight is up to hand
filing the cruciform tip in any smaller dia rod, hence a request for
help !!
My BC221 is still furkling along after 63+ years (& only c/s -
There, I've said it !!) out of calibration) but I think I should at
least try & smarten up the case with a good clean and a bit of fresh
paint. Who knows, it's probably got more chance of making the century
than I have.
Thanks
--
Dick
GM0MNL

Correction, that should have been WEINER not WIENER!

Malcolm

"Dick" wrote in message
...
I'm trying to get a hold of a tool that will undo grub screws
securing the front panel knobs on my venerable BC221, can anyone suggest
where I can get a hold of one, a modern equivalent and/or something that
can be modified to do the job ??
Although all BC221s were provided with the tool (stored in a
clip beside the spare valves) I've never seen one and can only guess
that it must be something like a very small Phillips screwdriver head
but with a parallel rather than tapered tip. It must also be less than
3/32" dia 'cos I've just tried to make one by hand out of 3/32" dia
steel rod and that was too big, don't think my eyesight is up to hand
filing the cruciform tip in any smaller dia rod, hence a request for
help !!
My BC221 is still furkling along after 63+ years (& only c/s -
There, I've said it !!) out of calibration) but I think I should at
least try & smarten up the case with a good clean and a bit of fresh
paint. Who knows, it's probably got more chance of making the century
than I have.
Thanks
--
Dick
GM0MNL

Correction, that should have been WEINER not WIENER!

Malcolm

"Dick" wrote in message
...
I'm trying to get a hold of a tool that will undo grub screws
securing the front panel knobs on my venerable BC221, can anyone suggest
where I can get a hold of one, a modern equivalent and/or something that
can be modified to do the job ??
Although all BC221s were provided with the tool (stored in a
clip beside the spare valves) I've never seen one and can only guess
that it must be something like a very small Phillips screwdriver head
but with a parallel rather than tapered tip. It must also be less than
3/32" dia 'cos I've just tried to make one by hand out of 3/32" dia
steel rod and that was too big, don't think my eyesight is up to hand
filing the cruciform tip in any smaller dia rod, hence a request for
help !!
My BC221 is still furkling along after 63+ years (& only c/s -
There, I've said it !!) out of calibration) but I think I should at
least try & smarten up the case with a good clean and a bit of fresh
paint. Who knows, it's probably got more chance of making the century
than I have.
Thanks
--
Dick
GM0MNL

You are correct Bob, according to the SCR-221 technical manual
(TM-11-300) there should be two Bristol wrenches (#6 & #8) in the
spares kit. I have just tried the one I have on an old wreck of a
BC221-T and it fits but don't know whether it is a #6 or a #8. It
is just under a 1/10" across the flutes.

I believe that during WWII there was a specially employed
lady, complete with tattoos presumably, whose task it was to
tighten the set-screws on all military equipment. She did such a
good job that nobody except a certain candidate for the
governorship of California has since been able to move them.



I have seen the wrenches on e-bay from time to time.

To remove the screws after ordering a bowflex machine and working out with
it for 6 months, heat them and the "glue" will release and you will be able
to turn them.

You are correct Bob, according to the SCR-221 technical manual
(TM-11-300) there should be two Bristol wrenches (#6 & #8) in the
spares kit. I have just tried the one I have on an old wreck of a
BC221-T and it fits but don't know whether it is a #6 or a #8. It
is just under a 1/10" across the flutes.

I believe that during WWII there was a specially employed
lady, complete with tattoos presumably, whose task it was to
tighten the set-screws on all military equipment. She did such a
good job that nobody except a certain candidate for the
governorship of California has since been able to move them.



I have seen the wrenches on e-bay from time to time.

To remove the screws after ordering a bowflex machine and working out with
it for 6 months, heat them and the "glue" will release and you will be able
to turn them.

Mike W wrote:

On Mon, 18 Aug 2003 17:00:04 +0100, Dick
wrote:

I'm trying to get a hold of a tool that will undo grub screws
securing the front panel knobs on my venerable BC221, can anyone suggest
where I can get a hold of one, a modern equivalent and/or something that
can be modified to do the job ??
Although all BC221s were provided with the tool (stored in a
clip beside the spare valves) I've never seen one and can only guess
that it must be something like a very small Phillips screwdriver head
but with a parallel rather than tapered tip. It must also be less than
3/32" dia 'cos I've just tried to make one by hand out of 3/32" dia
steel rod and that was too big, don't think my eyesight is up to hand
filing the cruciform tip in any smaller dia rod, hence a request for
help !!
My BC221 is still furkling along after 63+ years (& only c/s -
There, I've said it !!) out of calibration) but I think I should at
least try & smarten up the case with a good clean and a bit of fresh
paint. Who knows, it's probably got more chance of making the century
than I have.
Thanks
Dick, I think they are "Allen Key" or "Hex Key" grub screws but I
won't bet on it though.
hth Mike W, G8NXD

I vote for the Bristol answer. I think I have a couple here but it would
probably take a "crime scene" investigation to find them. I have a couple of
BC221
and the newer version with a CRT.

Bill K7NOM

Mike W wrote:

On Mon, 18 Aug 2003 17:00:04 +0100, Dick
wrote:

I'm trying to get a hold of a tool that will undo grub screws
securing the front panel knobs on my venerable BC221, can anyone suggest
where I can get a hold of one, a modern equivalent and/or something that
can be modified to do the job ??
Although all BC221s were provided with the tool (stored in a
clip beside the spare valves) I've never seen one and can only guess
that it must be something like a very small Phillips screwdriver head
but with a parallel rather than tapered tip. It must also be less than
3/32" dia 'cos I've just tried to make one by hand out of 3/32" dia
steel rod and that was too big, don't think my eyesight is up to hand
filing the cruciform tip in any smaller dia rod, hence a request for
help !!
My BC221 is still furkling along after 63+ years (& only c/s -
There, I've said it !!) out of calibration) but I think I should at
least try & smarten up the case with a good clean and a bit of fresh
paint. Who knows, it's probably got more chance of making the century
than I have.
Thanks
Dick, I think they are "Allen Key" or "Hex Key" grub screws but I
won't bet on it though.
hth Mike W, G8NXD

I vote for the Bristol answer. I think I have a couple here but it would
probably take a "crime scene" investigation to find them. I have a couple of
BC221
and the newer version with a CRT.

Bill K7NOM

You might check inside the instrument. A Bristol wrench was often
included in military gear under a clip someplace.

I don't have a Bristol wrench for comparison any more, but I recall
their cross sectional shape as resembling modern Torx drivers. It would
probably take an unusually long one, and if it didn't fit well there'd
be a danger of chewing the screw so it'd never come out. Might be worth
investigating, though.

Roy Lewallen, W7EL

Bill Janssen wrote:

I vote for the Bristol answer. I think I have a couple here but it would
probably take a "crime scene" investigation to find them. I have a couple of
BC221
and the newer version with a CRT.

Bill K7NOM

You might check inside the instrument. A Bristol wrench was often
included in military gear under a clip someplace.

I don't have a Bristol wrench for comparison any more, but I recall
their cross sectional shape as resembling modern Torx drivers. It would
probably take an unusually long one, and if it didn't fit well there'd
be a danger of chewing the screw so it'd never come out. Might be worth
investigating, though.

Roy Lewallen, W7EL

Bill Janssen wrote:

I vote for the Bristol answer. I think I have a couple here but it would
probably take a "crime scene" investigation to find them. I have a couple of
BC221
and the newer version with a CRT.

Bill K7NOM

Joe McElvenney wrote:

Hi,

You are correct Bob, according to the SCR-221 technical manual
(TM-11-300) there should be two Bristol wrenches (#6 & #8) in the
spares kit. I have just tried the one I have on an old wreck of a
BC221-T and it fits but don't know whether it is a #6 or a #8. It
is just under a 1/10" across the flutes.

I believe that during WWII there was a specially employed
lady, complete with tattoos presumably, whose task it was to
tighten the set-screws on all military equipment. She did such a
good job that nobody except a certain candidate for the
governorship of California has since been able to move them.


Cheers - Joe


I put a drop of "Breakfree" in the hole and wait a couple days to
remove tight screws.
--


Michael A. Terrell
Central Florida