Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris

On Tue, 26 May 2020 16:17:14 -0700 (PDT), Christopher Tidy
wrote:

Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Vibra-Tite is probably valve grinding paste. It will chew the brass
surfaces up in short order.

To increase friction between brass surfaces, a dry leather works
washer well. Form the washer into a rough hemisphere while wet, let
dry.

Joe Gwinn

"Christopher Tidy" wrote in message
...

Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to
protect the black-and-white film. I like the style, so I'm converting it
into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2"
diameter, and the power cable passes through the centre). The joint is held
stiff by an internal compression spring, but this isn't quite providing
enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the
spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits
into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something
like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris

Googling "Vibra-TITE 470 DriveGrip sds" gives the SDS as the first hit (I
got lucky, sometimes they are buried), and that says that the dangerous
components include silicon carbide 20-29%, thickening agent (combustible
dust) 5-9%, and something called intermediate copolymer 1-4% (probably
another thickener), so yes, it's an abrasive that will grind away your
brass. How fast? No idea - this is Usenet, what do you want, a complete
authoritative answer :-) :-)? Wonder how long a layer of clear acrylic
spray paint would last on the ball, given how infrequently I'm assuming you
will be adjusting it?

--
Regards,
Carl Ijames

"Christopher Tidy" wrote in message
...

Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to
protect the black-and-white film. I like the style, so I'm converting it
into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2"
diameter, and the power cable passes through the centre). The joint is held
stiff by an internal compression spring, but this isn't quite providing
enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the
spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into
the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like
that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris

============================================

I'd try paper in the joint first.

On 5/26/2020 4:17 PM, Christopher Tidy wrote:
Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris


Vibratite maybe... never used it, but some airgun guys use them on
adjustable metering set screws.

On Wednesday, May 27, 2020 at 6:45:53 PM UTC-5, Bob La Londe wrote:
On 5/26/2020 4:17 PM, Christopher Tidy wrote:
Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris


Vibratite maybe... never used it, but some airgun guys use them on
adjustable metering set screws.

I have not used this brand but I have used this type of "screw Grip" before and it is a gritty compound... If you are concerned about the finish do not use it. It does work well on moderatly stripd phillips screw heads.

soundguy.paul

On Thu, 28 May 2020 08:58:00 -0700 (PDT),
wrote:

On Wednesday, May 27, 2020 at 6:45:53 PM UTC-5, Bob La Londe wrote:
On 5/26/2020 4:17 PM, Christopher Tidy wrote:
Hi folks,

I have an old darkroom lamp from the 1960s. It originally had a red bulb to protect the black-and-white film. I like the style, so I'm converting it into a desk lamp.

It has a pair of ball-and-socket joints in the arm (ball is about 1/2" diameter, and the power cable passes through the centre). The joint is held stiff by an internal compression spring, but this isn't quite providing enough friction.

I had wondered about fitting a stiffer spring, or trying to stretch the spring a little, but I'm not sure how easy or wise this is.

I'm now thinking of squirting some tip grip liquid for screwdriver bits into the joints instead. Something like this:

https://www.amazon.com/-/de/Vibra-TI...dp/B008RMT63A/

Does anyone know what's in this liquid? Is it carborundum, or something like that, which might cause serious joint wear?

The joints are made from hard brass.

Thanks!

Best wishes,

Chris


Vibratite maybe... never used it, but some airgun guys use them on
adjustable metering set screws.

I have not used this brand but I have used this type of "screw Grip" before and it is a gritty compound... If you are concerned about the finish do not use it. It does work well on moderatly stripd phillips screw heads.

soundguy.paul
Basically it is just valve lapping compound - fine - repackaged.
Would quickly damage the brass ball/socket joint