How do I remove a woofer from a cabinet that seems to be stuck?

worked beautifully. Pot is silent now.
Now I’m tempted to pull my vintage Pioneer SA 8100 out and try to Deoxit those pots

 

my 3.5 year old: “daddy, I probably did that when I was a baby.”

 

So glad you got in!

 

I'm a former professional tech with IBM and have worked in the service dept of a hifi dealer
I'd like to offer some info, some lecture, and advice:

Deoxit will introduce corrosive acid to your SA-8100 pots and switches. The SA-8100 tone "pots" are special design and expensive to replace. There are no non-OEM replacements. The chances are, the problem isn't corrosion but only dust. As for the function selector, the "knife" contacts may appear oxidized (blackened) but this is NORMAL and should not be removed. The actual contact surfaces are self cleaning, but may have some adhered dust which needs a little help with contact cleaner. The petrol based preserver introduces a foreign substance not found in any high quality pot or switch contact. The internal parts are designed to be clean and dry.

The active ingredients in deoxit are not necessary, and are harmful to your unique and hard to find pots and switches. The oil preserver is an insulator, and normally impairs intimate electrical contact. So this is resolved by adding a conductive additive... which then causes an electrical path to ground. The values of your pots and switches will be slightly altered, and the sound of your amp potentially altered.

The primary cleaning/flushing agent in deoxit is contact cleaner, so why not use straight contact cleaner?

Contact cleaner leaves no residue, so the signal integrity will never be altered.

Deoxit has become a 21st century cult. Those who use it defend it like the second coming.

Do not use deoxit.

The very best favor one could do to their vintage switches and pots is straight contact cleaner without lube... no lube.

Potentiometer traces and wipers are self lubricating, and should be clean and dry. Pots and switches are designed to operate clean and dry!

Why contaminate perfectly good contacts with a corrosive chemical agent? Of course acid does dissolve corrosion, BUT on contacts NOT corroded the acid itself is corrosive. (in other words, why intentionally corrode your switches and pots?) The preserver is not 100% effective in preventing oxidation... and acid accelerates it!

So, I hope my explanation will save one more vintage device from the jaws of deoxit!
Without fail, a few deoxit cultists will "holler and scream" about my posting, dismiss the consequences and defend this awful product.

good luck
Steve VK

 

Glad it worked out for you! And you’ve probably discovered by now, it’s a very sticky gasket similar to what’s used on a car windshield. If you feel like experimenting, on my Snell Type KII, I bypassed the tweeter pot with a fixed Ohmite resistor, measured where I thought the tweeter level was perfect. Took out some of the graininess that I thought came from that tweeter pot. Also replaced the wiring.

 

Very interesting. I’ll take your advice to heart. Thanks!

 

I need to replace the original electrolytic xover caps in my 2 pairs of Dynaco A-35's and want to clean the resistor selector pots. Any specific contact cleaners you recommend? Brands?

Also DeOxit makes what they call "Contact Cleaner" so does this contain the acid you mentioned?

 

Thanks for the great idea! I am planning on changing the caps on 2 pairs of vintage Dynaco A-35 speakers which use some type of black tar like material to seal the drivers to the cabinets. I had read the drivers are a real pita to remove so will try your suggestion.

 

The corkscrew worked great, but I had to try two of them. The first one didn’t have enough “hook” on it.

 

Hey classicrocker, CRC is the most popular brand. I still have an old can of Radio Shack contact cleaner, cat # 6404345 that works great (contains no lubricant) Avoid contact cleaner that contains lubricant. It is a myth, that lubricant is needed for smooth operation and longer life (seems reasonable but no truth to it) However, I have used dry silicone spray on open contacts such as function selector switches, just to slow any oxidation that occurs on this type of switch. Function selector switch contacts are self cleaning, so even the dry silicone "preserver" really isn't necessary.

Contact cleaner evaporates quickly, so each pot or switch must be operated quickly before the "juice" evaporates. Short bursts are better than "fire hosing" since we do not want the contact cleaner getting into the shaft bearing which washes oil or grease onto the wiper and trace. The improper application of contact cleaner can cause this problem that did not exist before.

Such a simple operation can cause headaches when not carried out correctly. Of course, sometimes a very stubborn pot or switch must be "fire hosed" as a last resort. If/when the shaft lube washes on the electrical parts, continue to "fire hose" until it is flushed out. The pot will then have lost its viscous damped action, and will turn too freely. (will operate normally otherwise) Some pots are viscous damped, others aren't. For example, CTS pots for guitars and amps are not damped and turn very freely... on the other hand, most Stereo Hifi gear such as vintage Pioneer will be damped and have a smooth "buttery" feel.

In worst case scenarios, the pot or switch may be oxidized, which then deoxit should take care of it (nothing to lose in such case)
The BEST fix for a stubborn pot or switch is to remove from chassis, take it apart, and manually polish the contact surfaces with micro-polish. I have done this on several occasions with 100% success. However, the carbon trace inside the pot should never be micro-polished. Simply clean with Q tip and isopropyl or contact cleaner, blow with a can of air.

CRC QD is plastic safe, and a slower evap rate, and less rapid cool down of the carbon trace. MG brand offers a silicone lube version, ok because dry silicone allows full electrical contact, is non-conductive and does not adhere dust to itself.

https://www.amazon.com/CRC-Industries-03130-Contact-Cleaner/dp/B07MLNFBVL
https://www.amazon.com/s?

Amazon.com: mg contact cleaner

I believe Caig deoxit offers (non-deoxit) contact cleaner, should be perfectly safe to use!
Seems like a lot of detail in writing, but in practice it's easy,
Steve VK.

 

Thanks Fringe, just ordered a can of the CRC contact cleaner.

Will use it during the recapping of my Dynaco's

 

There is a tool called a Richards Roofing knife that I bought specifically for removing woofers held in place by adhesive.

It worked splendidly for that and became one of my most often used tools