Safely disinfecting electronics

[hayerjoe]

hello all

Just acquired a new radiogram, a barn find but savable I think. On opening it up i noticed the lower part of the chassis was covered in about 1cm of mouse dropping's (nice). With a combination of mask, vacuum and a pick I loosened and removed pretty much all of it, but it feels far from 'clean'. My questions are:

1) I'd like to disinfect it all before I send it away for checks and repairs, what can I use (if anything) that would be safe on the components? and how should I apply it?
2) the droppings have caused a lot of rust on the bottom section (see photo), although this is unsightly what damage could it have caused to components (I see a bit of green corrosion on connections) ? and going forward how should I treat the chassis? (leave as-is, rust is its own protective coating; paint it?other? etc)

Look forward to your replies
Joe

[Diabolical Artificer]

On a Tektronix scope that had similar mouse crap in I scrubbed it out with watered down bleach, that's everything,components et al. You have to be a bit careful and not scrub too hard on PCB's. I blew said scope out with compressed air and dried with rags then left it near the fire for a week.

Andy.

[sortedradio]

Isopropyl alcohol is a good disinfectant and harmless to most electronic components.

[ortek_service]

Ultra-violet light is often used for killing bacteria / even Sterilising dirty water to make it safe to drink, even if it doesn't actually make it look that clean.

And as strong sunlight is also meant to kill viruses, then exposing it to this for a while might be helpful - Heating is also frequently-used to sterilise / kill-off bacteria, so heat from it may help, providing there aren't any particularly heat-sensitive parts on it. But I suppose you might want to make it visually clean, first, rather than risk baking-on any existing muck (which if droppings, then could well be acidic / alkali, so probably need to neutralise to prevent corrosion of metals)

[paulsherwin]

Originally Posted by sortedradio

Isopropyl alcohol is a good disinfectant and harmless to most electronic components.

Agreed, you can buy IPA sprays for little money and it will just evaporate over time. You will need to clean most of the crud off first of course.

[Radio Wrangler]

IPA is also a useful solvent, so apart from disinfecting things, it will also help you remove the muck.

David

[murphyv310]

Hi.
I've been strongly criticised in the past how I clean things up but have never had an issue. I would remove the chassis and mix up a 25% solution of Traffic Film Remover (TFR) 75% water in a trigger spray bottle and spray it over the entire chassis. Let it stand for a few minutes and rinse it off with a pressure washer fan spray or a good hose with decent tap pressure. Blow it with an air line and dry with a hairdryer, leave in a warm place with good ventilation for a week and all will be fine.

The photos show a set that was literally filthy with all sorts of unknown things I dread to imagine what they were.

[hayerjoe]

Thanks everyone, some good ideas there. As a starter I'll get some IPA as it sounds useful for other things as well

No-one commented on what I should do with the chassis when clean. Just leave it as dry surface rust will be ok?

[kellys_eye]

We use Milton fluid for disinfecting - high on all the recommendations for commercial kitchens - and given it also removes turmeric stains from white worktops....!!!

[Restoration73]

Also be aware of other creatures found on equipment from a non-sterile environment.

Equipment can harbour woodworm, fleas, bedbugs, and ticks.

[paulsherwin]

Originally Posted by hayerjoe

No-one commented on what I should do with the chassis when clean. Just leave it as dry surface rust will be ok?

It depends on your personal preference and how much work you want to put in - you could do anything from leaving it alone to sandblasting it. I would treat it with a commercial paint-on anti-rust treatment or spray it with WD40, but then the UK climate has high humidity levels and Tas may be drier.

[Glowing Bits!]

A word of caution when using IPA, it needs watering down before use, this slows down the evaporation, it usually evaporates in 1 second otherwise.
Another recommendation is to wear gloves, IPA can and does cause a tingling/burning sensation when on skin and tends to dry skin in the process.
Anothing thing worth considering would be brake cleaner, it's safer than IPA.

[hayerjoe]

Originally Posted by paulsherwin

It depends on your personal preference and how much work you want to put in - you could do anything from leaving it alone to sandblasting it. I would treat it with a commercial paint-on anti-rust treatment or spray it with WD40, but then the UK climate has high humidity levels and Tas may be drier.

Well hopefully it will never be relegated to a damp garage whilst in my possession, so I think after a good clean, and a good drying, I'll remove as much loose rust as possible and then just WD it!

Thanks

FYI - Tasmania is about as damp as the driest bit of UK, so quite damp by Australian terms

[hayerjoe]

Originally Posted by Glowing Bits!

A word of caution when using IPA, it needs watering down before use, this slows down the evaporation, it usually evaporates in 1 second otherwise.
Another recommendation is to wear gloves, IPA can and does cause a tingling/burning sensation when on skin and tends to dry skin in the process.
Anothing thing worth considering would be brake cleaner, it's safer than IPA.

Thanks for the guidelines.

Brake fluid eh, is there anything it can't do? I posted on here about it restoring my old and totally stiff 1954 BSR platter mat

[Glowing Bits!]

Originally Posted by hayerjoe

Thanks for the guidelines.

Brake fluid eh, is there anything it can't do? I posted on here about it restoring my old and totally stiff 1954 BSR platter mat

Brake fluid and brake cleaner are different things, brake cleaner is alcohol, on the flip side, brake fluid is stuff used in a hydraulic system, it will destroy most rubber stuff pretty damn quick.

[TonyDuell]

Originally Posted by Glowing Bits!

Brake fluid and brake cleaner are different things, brake cleaner is alcohol, on the flip side, brake fluid is stuff used in a hydraulic system, it will destroy most rubber stuff pretty damn quick.

That must depend on the 'rubber'. Many hydraulic systems, and all braking systems that I've ever worked on contain rubber seals, which are normally ruined if they come into contact with mineral oil (such as most lubricants). Brake fluid does attack many paints though.

I've used IPA for cleaning disk and tape heads, switch contacts, mechanical bits, etc with no ill effects to me or the item being cleaned.

[paulsherwin]

Almost all 'rubber' seals used in modern equipment are actually some form of neoprene rather than anything from a tree in Malaysia. It's best to err on the side of caution if there's any doubt though, as failure is usually catastrophic.

[hayerjoe]

oops thanks fellas... I mis-read 'cleaner' for 'fluid' big difference!!

Also there are different flavours of brake fluid, Dot3, Dot4, Dot5 etc, and this is in part due to the type of plastic and rubber-like bits in a particular brake system. I was told only use Dot3 or 4 on my real rubber platter mat

thanks again for pointing out my potentially disastrous mis-reading

[Cruisin Marine]

I use those small steam cleaners for kitchen use, NOTHING survives steam, remove any valves etc. before you do though, and avoid any veneer and glue in joints, do it quickly and sparingly

[Glowing Bits!]

A UVC tube could be used but would trash most plastics including cables.
A better method with guaranteed results would be gamma rays, this is usually used in hospitals for sterilising utensils after an operation.
Trying to acquire one of these devices is prohibitively expensive and potentially life threatening when in operation, it's out of the question.