Proper use of Deoxit

[Tomm Williams]

Testing out a pair of Valley People Gatex processors and have a little bit of scratchy pots. The more I work them the better it gets but still a little noisy while panning. Bought some Deoxit but don't want to just start spraying away. What precautions should I follow ? How quickly does this stuff evaporate before I dare pass signal through the unit ?

[wesg]

I'm certainly not the expert here, but one thing I want to mention is that pots are made with some lubricant on the carbon tracks to keep the wiper from damaging the carbon. When you use contact cleaner, you can dissolve this lubricant. That is why Iuse DeOxit FaderLube when cleaning pots. The FaderLube is a contact cleaner that will also replace the factory lubricant.

[WRGKMC]

Definitely make sure you use the lubricating Deoxit. They do have a couple of types that are lubricating and some that are zero residue.

The two lubricating types of contact cleaners use either silicone or mineral oil. Mineral oil has been used forever and in my opinion is superior

to silicones that dry up quickly. If the pots are new that silicone can work OK but worn pots do better with the mineral oil based cleaners.

(at least from my 40+ years as an electronic repairing gear for a living)

 

Mineral oil seems to dampen the sparks between the carbon pad and steel wiper and even if the pots are worn it greatly reduces pot noise.

 

For cleaning its always best to get inside the unit and spray inside the pot with the plastic tube so you douse the contacts.

 

In your particular case, I took a look at a pic of the Valley People Gatex processor modules.

It looks like it has those square sealed PC mount pots which have no openings to clean them.

I had those in my Half Rack Rocktron drive unit. The pots got real scratchy and you couldn't get inside of them to clean them.

I tried burning holes in the plastic to get some cleaner in them. It worked for maybe a few days tops.

 

So the bad news is, when those particular pots go bad, they have to be replaced. That's why they are sealed.

Since they are PC mount you have to de-solder them, especially if the board is multi layered and has traces on both sides.

Its best if you can find the schematic to find the pot values too. You can measure the pots after they but you wont know what the taper is.

Chances are they are in the 5~10K range and linear tapered but I'd have to test them to know.

 

Whatever you do is don't go spraying non residue cleaner around. If you do squeeze some inside through cracks

those pots will crap the bed in no time. You have partical operation now and the pots are packed with conductive grease.

that's what gives them the plush feel when you turn the knobs. Non residue cleaner will cause that grease to fail and

the scratchy noise will get many times worse. Best thing you can do is shop for the right pots and have someone put them in for you.

Or better yet get someone experienced to get the right pots for you and put them in.

 

[agedhorse]

The only products that we use (from the manufacturing side) is DeOxit D5 or F5, and just a tiny bit of spray. The D5 is a little more agressive (better on older gear), both have embedded lubricants, both are safe on the baked carbon elements that are used on all of the typical Alps/Noble type pots (including the ones on the Valley People products). A small amount goes a long way. I think this is likely to be 100% successful on your units. The spray enters from the lead side between the housing and leads there is a space. You will need to bend the spray tube creatively to get in there.

 

To dispell some myths here, the contacts are not steel, they are generally a plated phosphor-bronze and they ride on a baked carbon carbon track with the wiper riding on a baked silver inked track. The pots are not packed with grease, there is a thin film between the shaft and the bushing and the rotating thrust washer and bushing. This is why a small amount goes a long way, it is possible to damage this film.

 

... and never use anything else, there's too many variables within different manufacturer's products to even risk it.

[Pro Sound Guy]

If you have to replace the pots just contact VP and see if they will give you a source or send you some pots. AH can install them for you or you could do it yourself.

(USA) tel: 1 310 323 9050

They are in CAL

 

[agedhorse]

I might have the pots in stock, but I'm pretty sure they don't need replacement.

[Dogoth]

You will need to bend the spray tube creatively to get in there.

 

Funny, I have a couple of nozzle/tubes that are bent (one does about a 190 and looks lke a J ). I also have a flexible tube with a strait nozzle on one end and a short bent one on the other. It reduces velocity for cleaning a bit but allows you to get it just where you need it. WATCH YOUR EYES with any of these. I use the same tube arrangment with WD-40, PB blaster and other solvents (and purge it well between uses). It's been very handy :-).