The Reference 6SN7 Thread

[LoryWiv]

go to post #737 of this thread and read on..

Ah. great pointer, thanks man!

 

[cddc]

Take one for the team and let us know how it worked out!

Will do, I'm gonna sacrifice a GE or RCA 12AU7 in the worst case scenario...at least it's not expensive

Or maybe it will turn out to be wonderful...

 

[cddc]

A safe way to remove oxidation is to get a Mr. Clean Magic Eraser and shove the pins into it a few times. The Magic Eraser is an abrasive plastic and will scour the oxidation off without any adverse effects.

Will try that too...I did buy some Mr. Clean Magic Erasers for car wash long time ago, but somehow never used them. Need to find them out and give it a shot. The inner circle of the pins is hard to reach though...

 

[JimL11]

Will try that too...I did buy some Mr. Clean Magic Erasers for car wash long time ago, but somehow never used them. Need to find them out and give it a shot. The inner circle of the pins is hard to reach though...

No need to overthink it, just hold the tube and shove the bottom right into the Eraser. With 7 and 9 pin miniature tubes, they just go right in up to the glass - a few times should clean all the pins at once. With octal tubes the Eraser gets deformed somewhat but it's not like the Eraser is a big expense.

 

[cddc]

No need to overthink it, just hold the tube and shove the bottom right into the Eraser. With 7 and 9 pin miniature tubes, they just go right in up to the glass - a few times should clean all the pins at once. With octal tubes the Eraser gets deformed somewhat but it's not like the Eraser is a big expense.

Plug-and-play...simple as that

I like it!

 

[bcowen]

Will do, I'm gonna sacrifice a GE or RCA 12AU7 in the worst case scenario...at least it's not expensive

Or maybe it will turn out to be wonderful...

Killing a GE is not a sacrifice. It's a gift to humanity in general.

 

[JKDJedi]

Killing a GE is not a sacrifice. It's a gift to humanity in general.

L M F A O !!!

 

[JKDJedi]

Ah. great pointer, thanks man!

https://www.ebay.com/itm/1-x-7N7-7F...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649 Strong 7N7 adapter..NOT like the CHiFi ones ...

 

[bcowen]

A question about the coating by Deoxit: I know the contaminants taken off by Deoxit need to be cleaned, but is isopropyl alcohol going to remove the protective coating formed by Deoxit?

The oxidation is much better on 6SN7 pins than on 12AU7 pins in general...you can still see the silver color on most 6SN7 pins, but most 12AU7 pins are black or dark blue, look damn dirty. So I am thinking if it is okay to try WD40 for pin cleansing? I still have a can of WD40 (specialist, rust release) left over from last time when I was trying to replace the car battery by myself. I think WD40 can penetrate and dissolve the rust/oxide. It might be okay to spray some WD40 to the 12AU7 pins, then let it sit for a while and scrub it off with isopropyl alcohol. I don't expect coating from WD40, so using isopropyl alcohol to clean it is perfectly fine here.

I guess it all depends on what your end goal is. If leaving a coating of the Deoxit in place as a preservative is the goal, then yes the alcohol will pretty much defeat that. I use Deoxit just to clean as it seems to lift off crud and oxidation better than most anything else I've tried (short of using an abrasive like sandpaper or emery paper). I don't want any of it left on there when I'm done though, which is why I follow with alcohol. There's lots of contact conditioners and preservatives out there, and I use a conditioner in a couple places in my system. But when it comes to tube pins (and moreso tube sockets), my preference is just metal-to-metal with the two surfaces as clean as possible. You can obviously clean tube pins at any point you want with relative ease, but if any of these conditioners or preservatives start to bake and crust onto the contacts of a tube socket, that becomes a much more difficult proposition to rectify. I'm not suggesting there's a right or wrong approach to this, just relating what I do and why.

I *do* like @JimL11 's suggestion of the magic eraser. I've never tried using one for this purpose, but for 9-pin tubes especially that sounds like an awesome idea.

 

[cddc]

Killing a GE is not a sacrifice. It's a gift to humanity in general.

LOL ...I agree. So I tried three GE's (two 12AU7's and one 6SN7GTB).

I cleaned all tubes first with isopropyl alcohol and Q-tips. The two 12AU7's before applying WD40 and Mr. Clean Eraser:

Then I sprayed some WD40 (penetrate specialist, rust release) to pins on the 12AU7 with lighter getter flash (this one seemed dirtier), and gave the pins a good scrub using Q-tip and WD40, followed by isopropyl alcohol. For the other 12AU7, I just shoved its pins into Mr. Clean Eraser multiple times (without WD40) until Mr. Clean became Mr. Holes... . And here's how they looked after cleansing:

I couldn't see any difference...had expected the black/blue/brown crud to be removed by WD40.

 

[cddc]

After seeing no changes, I picked up a GE 6SN7 with dirty pins. Again, cleaned it first with isopropyl alcohol and Q-tips. And here's how it looked after alcohol and before WD40 (the bottom one):

And here's how it looked after WD40:

Some little improvement here, and I suspect the little improvement came from scrubbing instead of from WD40. I didn't see anything dissolved by WD40, the residual still looked pretty clean.

So pretty disappointed with WD40. It works on rusted nuts very well, but is of little use here. And it smells even after cleansing the pins with isopropyl alcohol afterwards.

I think I should try Deoxit next time as per @JKDJedi and @bcowen.

 

[cddc]

I guess it all depends on what your end goal is. If leaving a coating of the Deoxit in place as a preservative is the goal, then yes the alcohol will pretty much defeat that. I use Deoxit just to clean as it seems to lift off crud and oxidation better than most anything else I've tried (short of using an abrasive like sandpaper or emery paper). I don't want any of it left on there when I'm done though, which is why I follow with alcohol. There's lots of contact conditioners and preservatives out there, and I use a conditioner in a couple places in my system. But when it comes to tube pins (and moreso tube sockets), my preference is just metal-to-metal with the two surfaces as clean as possible. You can obviously clean tube pins at any point you want with relative ease, but if any of these conditioners or preservatives start to bake and crust onto the contacts of a tube socket, that becomes a much more difficult proposition to rectify. I'm not suggesting there's a right or wrong approach to this, just relating what I do and why.

I *do* like @JimL11 's suggestion of the magic eraser. I've never tried using one for this purpose, but for 9-pin tubes especially that sounds like an awesome idea.

Good points...for conditioners there is Deoxit Gold. But metal-to-metal contact should be the best.

I tried WD40 with little success, it didn't dissolve crud and oxide on pins. So I should try Deoxit next time.

 

[bcowen]

LOL ...I agree. So I tried three GE's (two 12AU7's and one 6SN7GTB).

I cleaned all tubes first with isopropyl alcohol and Q-tips. The two 12AU7's before applying WD40 and Mr. Clean Eraser:





Then I sprayed some WD40 (penetrate specialist, rust release) to pins on the 12AU7 with lighter getter flash (this one seemed dirtier), and gave the pins a good scrub using Q-tip and WD40, followed by isopropyl alcohol. For the other 12AU7, I just shoved its pins into Mr. Clean Eraser multiple times (without WD40) until Mr. Clean became Mr. Holes... . And here's how they looked after cleansing:


I couldn't see any difference...had expected the black/blue/brown crud to be removed by WD40.

That bluish-brown color is heat discoloration from melting the glass around the pins in the manufacturing process. One thing I know that will remove it: Blue Away. Dumb expensive, but it works. We use it at work for getting brown welding spots off of stainless. But.....I can't say that I've heard any audible difference after using it on tube pins (and cleaning the excess off with alcohol) versus a good scrub with Deoxit and an alcohol rinse. Just makes the pins prettier. Most are steel, so it's not like they'll be all bright and shiny...just less 'multicolored' looking afterwards.

https://simichrome.factoryoutletsto...category_id=29487&ci=eNkZZk2WiBmm7RKDz9Samg==

 

[cddc]

You are right, the bluish-brown discoloration should be the burns from melting the glass. Surprised to hear that there's indeed some solution to remove it. Learning something new is always good

I don't really mind the discoloration on pins, all I need is a good contact between pins and sockets. So Deoxit should be good enough. Or if I really want to take the discoloration off, sandpaper should always work.

 

[bcowen]

You are right, the bluish-brown discoloration should be the burns from melting the glass. Surprised to hear that there's indeed some solution to remove it. Learning something new is always good

I don't really mind the discoloration on pins, all I need is a good contact between pins and sockets. So Deoxit should be good enough. Or if I really want to take the discoloration off, sandpaper should always work.

Emery paper works quite well, just kind of a PITA to use. The Blue Away is much easier...a bottle of it appeared on my work desk at home a while back, and I have no idea where it came from. I rarely go to the trouble of using it though as it just improves things visually...the Deoxit is plenty enough sonically.