Grease for the VOLTS/DIV and the SEC/DIV Controls on TDS Series 310, 320, 340, 350, 382, 420, 430


Bru H
 

I am cleaning up the Front Control PCB (A4 Front Panel Board) on a TAS465.
TDS Series 310, 320, 340, 350, 382, 420, 430 use the same type of PCB Printed Control. I believe all of TEK Scopes during the 90's era used the same design.

The Controls are a Simple Wiper that makes contact with carbon element pads on the PCB.
Tek had some sort of original Black grease to lube the rotation of the Wipers.
What type of grease should I apply to the Carbon Element Pads to Lube the Wipers?

I have the following:
GC Electronics Conductive Grease
Silicon Grease (Food Grade)
CRC Bulb & Connector Di-Electric Grease
CRC 2-26 Multi-Purpose Precision Lubricant

Thank you!
Bru


Daveolla
 

This is always a popular and always an informative discussion when it comes up often, I don't know where all the responders are!

A good question is what the difference is in the construction of the carbon on the board today and 30, 40, 50 years ago, and if certain chemical concoctions are good or bad for it.

I would think more responses might come from listing what they say they are for and what chemicals are in each of the compounds you listed, and also help others to apply this to similar compounds they might have.

Dave

At 08:42 PM 10/30/2021, you wrote:
I am cleaning up the Front Control PCB (A4 Front Panel Board) on a TAS465.
TDS Series 310, 320, 340, 350, 382, 420, 430 use the same type of PCB Printed Control. I believe all of TEK Scopes during the 90's era used the same design.

The Controls are a Simple Wiper that makes contact with carbon element pads on the PCB.
Tek had some sort of original Black grease to lube the rotation of the Wipers.
What type of grease should I apply to the Carbon Element Pads to Lube the Wipers?

I have the following:
GC Electronics Conductive Grease
Silicon Grease (Food Grade)
CRC Bulb & Connector Di-Electric Grease
CRC 2-26 Multi-Purpose Precision Lubricant

Thank you!
Bru



Jim Adney
 

On Sat, Oct 30, 2021 at 08:42 PM, Bru H wrote:

I have the following:
GC Electronics Conductive Grease
Silicon Grease (Food Grade)
CRC Bulb & Connector Di-Electric Grease
CRC 2-26 Multi-Purpose Precision Lubricant
Dielectric greases are generally intended as insulators, so I would not go that direction. The silicone grease would probably be a good lubricant, but the conductive grease, probably carbon loaded, sounds like the right product. Use sparingly.


Dallas Smith <dosmith2@...>
 

Bru,

I have used for audio applications, Fader Lube from DeoxIT.

https://caig.com/fader-f-series/

Dallas


73_Fred
 

Siemens-Kontaktsatz-Wählerfett V (Vaseline)


Bru H
 

I am leaning toward the CG Electronics "Conductive Grease and Anti-Oxidant" - "Dissipates Static Electricity"
I will try to call the Company Monday but they may be out of business or bought out.

The Youtube video "Tektronix TAS 465 Simple Service Tips"
Shows him Cleaning the PCB but he did not show, or make mention about applying grease.


Thank you.


Edward Prest
 

From my notes, source unknown , here are typical contact cleaner contents:..

1, 1-Difluoroethane (CAS 75-37-6) the propellant gas like refregarant

White mineral oil (CAS 8042-47-5)

Poly Dimethyl Siloxane (CAS 63148-62-9)

The silicone allows for reducing viscosity under pressure, like a contact wiper.

Thixotropy is a time-dependent shear thinning property. Certain gels or fluids that are thick or viscous under static conditions will flow (become thinner, less viscous) over time when shaken, agitated, shear-stressed, or otherwise stressed (time dependent viscosity).


Jordan
 

I've been using MG Chemicals Carbon Conductive Grease for over 30 years now...It's black with carbon and lasts a very very long time.

I learned about it while working in production for fibre-optic lottery terminals where the static would build up due to the nylon rollers, rubber drive rings and metal rollers and metal frames of the pickup assembly that pulled lottery tickets through so they could be read...

I know MG Chemicals is still around as I use a lot of their products, such as contact cleaners etc...

73...Jordan VE6ZT


Roy Thistle
 

On Sun, Oct 31, 2021 at 06:50 AM, Jim Adney wrote:


Dielectric greases are generally intended as insulators, so I would not go
that direction. The silicone grease would probably be a good lubricant, but
the conductive grease, probably carbon loaded, sounds like the right product.
Use sparingly.
AFAIK... there is sufficient contact resistance between the wiper and track (at least as the pot is designed, and is new) to displace a thixotropic non-conductive lubricating grease, like a silicone oil thickened with teflon... in such a way as not to affect the contact resistance significantly.
I am less sure about a conductive grease.. at least as it consists of a mechanical mixture of a non-conductive grease and conductive particles (like carbon).
In such a case, under the shear force of the contact, the conductive grease may be dilatent... and so work to significantly increase contact resistance.... or the conductive particles, on their own, may interfere.

--
Roy Thistle


Roy Thistle
 

On Mon, Nov 1, 2021 at 12:54 AM, Edward Prest wrote:


White mineral oil (CAS 8042-47-5)

Poly Dimethyl Siloxane (CAS 63148-62-9)
They are used as lubricating oils... so being an oil, they are somewhat runny... and so these oils are mixed with a thickener to make a lubricating grease.
It's the thickeners, and stabilisers... necessary to make the lubricant stay in place, and the oil stay in the grease, that are the devils in the details.
I'd speculate that a tiny amount of pure, non-thickened mineral oil (like from a drug store) would be a safe lubricant (but, it may migrate into a plastic... depending on the plastic... and if it does... it may cause problems.)
The industrial grease automotive sensor manufacturers used on the plastic composition pots in their sensors might be good.

--
Roy Thistle


Bru H
 

It sound Like MG Chemicals #847 is the way to go. The smallest size is the 25ml for $27, I will probably never use it again and do not want to invest in it. Any other ideas?.