What would you do (beer spill on Model 12)?

[Josh68]

At a recent practice, my bandmate had a bit of a beer accident, and some - really not a lot - got on my Model 12 (mostly up around the gains and EQs, and really none down toward the channel faders or to the right side with the screen, SDCard, mains, headphones, etc). I switched it off and began cleaning off all visible liquid. Then I did the maybe not-so-smart thing and turned it back on. Nothing horrible happened, but there was pretty significant noise coming from two channels. So I turned it back off.

When I got it home, I removed all knobs and paddles and turned the thing over, thinking that after a while, I'd be taking it apart to clean the main board (all the pots, faders, and switches) probably just with distilled water (maybe isopropyl first, but not not sure), then letting everything thoroughly dry again before reassembling.

But the next morning, I decided to plug it back in and quickly see what was up. Turns out, there's no perceptible noise coming from any channel, and all channels work (I tried mics, not any directs, but expect they'd work the same).

So, the question is, should I still think about a full cleaning? Or, putting it another way, should I be concerned about (really pretty minor amounts of) beer residue inside the unit, or should I leave well enough alone and see how it goes for a while?

I've taken my 12 apart once to replace the original power switch, so this wouldn't be my first time opening it up, but that was a pretty minor job, and didn't involve cleaning anything.

Thanks for any advice.

 

[-mjk-]

Sorry that happened. But it doesn't sound too bad.

The following is educational information only. I am a retired manufacturing engineer with decades of electronic product manufacturing experience from PDB production through wave soldering operations. Use this information at your own risk. I am relating this information as a private individual and this is not to be construed as official advice from The Tascam Forums.

With the exception of certain types of capacitors and transformers, most electronics are basically waterproof. The mechanical devices like faders, encoders and potentiometers are going to be an issue. These days most PCBs are all SMD (Surface Mount Devices) and these are as waterproof as sand.

Step #1 is to get one of these so it will be on hand by the time you finish the cleaning operation.

Your basic idea of flushing the unit with distilled water is good. If the PCB is waterproof you can rinse the entire unit. I do not recommend any type of household cleaner or solvent. The idea is that the distilled water will flush the minerals and contamination from the spill but it is not active and therefore won't continue to do anything bad later on.

If there are transformers and non SMD capacitors then I wouldn't worry too much about rinsing the board. Just be aware that if the caps got soaked, at some point you'll most likely end up replacing them. An issue with spills is that the mineral content tends to corrode the components over time. Also, those deposits can cause short circuits and also encourage dendritic growth. I would try to carefully rinse the PDB as much as possible. Of course, if you can see where the spill is on the board you can confine the cleaning to that area.

Prepare the materials and some kind of a tub to do the rinse. Distilled water is cheap so go overkill in case you have some stubborn dried material that won't come off easily. You can use a soft brush but be careful not to damage the solder mask (the green coating on the PCB). Normally room temperature water and a soft toothbrush will not harm anything.

If you open it up and things are a real mess, you might consider removing the caps and the transformers and placing the PDB in the distilled water for a bath. If the water isn't doing the job then denatured alcohol is the next thing to try.

After the rinse, put the unit into an oven on the lowest temperature setting you can use. As long as you aren't above the normal temperate that the device was exposed to during manufacturing processes (such as wave or dip soldering) you will be fine. Alternatively you can use a hair dryer or a plastic bag with lots of desiccant gel packs. You need to ensure that the water is 100% gone. It's not a bad idea to place it in the sun for awhile as long as there are no photo-sensitive devices in the unit.

You'll need to replace the lubricants in the faders and pots and for that I recommend Caig Laboratories products. They have several products called DeOxit that will do the trick. I normally don't flush those items with the distilled water but as long as you spray them with the DeOxit, the water will not damage those components. If you find that the beer has definitely contaminated the faders/pots, then I recommend ordering a good cleaner from Caig as well as the DeOxit. I've had to use several products to solve contamination on hard cases. Sometimes, the standard "pot spray" won't clean the pots well enough on it's own. Check their website for more information.

I've done this many times over the years and you will be fine.

 

[Josh68]

Thanks so much, @-mjk-

I appreciate the detailed instructions. Sounds pretty much like what I've done in the past to resuscitate laptops with spills, with additional steps for pots and faders.

The cover is a great idea, but alas, this happened while the mixer was in use. True, though, maybe I could even cover it when it's just on and I'm not fiddling with levels.

 

[Josh68]

@-mjk-, do you recommend any specific DeOxit spray(s) and/or cleaner(s)? I'm finding the number of options kind of mind-numbing. Seems like D5 (the stuff with the VOCs) may be the best bet for a spray and their Electronic Cleaner Wash for if anything got down much into the pots and faders? Appreciate any additional thoughts. Thanks

 

[-mjk-]

I would start with the products on this page: Section 1: https://caig.com/deoxit-d-series/ because these are the "UNIQUE CONTACT/CONNECTOR TREATMENT, REJUVENATOR AND PROTECTOR" products. The description in the website pulldown mentions "cleaner" so this appears to be a multi-use product.

Since apparently not much was spilled, I would think that the general spray cleaner/conditioner would in in order. They have other products that are conditioners "enhancers" and "protectors" but aren't marketed as cleaners.

It's interesting that they even have wipes for cleaning guitar strings!

Section 9 is cleaners: https://caig.com/cleaners-washes-solvents-protectants/

If anyone is interested, I could tell the story of how I fixed (edit) WNEV's on-air news cast audio dropouts using a combination of these products on their Neve console.

 

[Josh68]

Thanks, @-mjk- . Looks like I was on the right path.