Wax Spilled in Amp - Removal Ideas?

[TheTornOne]

Hello,

I have been dealing with an amp that likes to crap out in some fashoin or another due to an infamouse spilling of a wax candle into one of the vents on the top my JCM2000 DSL 100 (long story).

Since that fatefull day my amp has been in to be serviced about a dozen and a hlaf times and about every 2 to 4 months some new issue arrises as a direct result of the wax melting when turned on, flowing under components, and as it dries it expands and destroys compenents and pops them off the board.

I am now trying to fix this problem myself once and for all as the repair place just keeps treating the symptoms (replacing caps and other components) and not dealing with the disease (the wax).

Most of the wax is on the trace sides of the boards so I figured I would start there first. My first idea was to take a clothes iron and some paper towels and try to absorb it that way, but I am unsure as to what temperature might start damaging components.

I have never met anyone who has had to deal with this before but maybe you all have some ideas.

Any thoughts or ideas would be great!

[tedmich]

typically boiling water is the best solution for solid wax on an object, including an emulsifying agent (detergent) helps disperse the wax for easier removal. Boiling water is NOT good for PCB/components, although some components are "washable" meaning they are designed to be cleaned (usually of solder flux) by washing with perfluorinated solvents or now citrus based cleaners. ChemTools PCB Wash can be used up to ~60C which is plenty warm, and MAY dissolve the wax; I would recommend testing some of the wax and maybe some of the replaced components (you saved them eh?) Xylene and naptha are solvents for wax, and too many other things...

The iron and paper towel sound good! Test a bit of the wax to see what the lowest iron temp that works is.

[Chuck H]

Thats a tricky problem. I might try to remove as much as possible mechanically (take an old plastic wallet card and cut it into strips). You don't want to use anything too sharp or abrasive. Be carefull not to damage the board and traces. Then, once youve removed the bulk of the wax, use a hair dryer set to low air and high heat to melt the remainder and soak it up with Q-tips and bits of paper towel. When it's all over you may need to do some repairs because of physical damage. But at least you'll know where.

Sorry, I don't know of a magic solvent or anything.

The old black fiber boards used in Fender amps were virtually dipped in wax it seems on some amps. So I don't think a small amount of residue left behind should be too bad.

Chuck

[defaced]

Most candle wax melts between 150 and 200F, and according to my candle making friend, the iron and paper towel idea does work. What I'd do is do one or two applications of the iron, basically until you think the board is getting warmer than you'd like, then I'd let it sit until it's cool and repeat.

Also, like Chuck has suggested, and my friend also suggested is to use a hair dryer which will make the wax malleable, as a way to possibly get it off of the component side of the board.

[gbono]

You might try to go the other way with temperature - try cold - like Coolzit. The best way to remove wax (actually desolve it on anything) is with the use of Freon. Good luck finding that today. Can you remove the PCBs and really get a good look at where the wax residue is hiding - don't for get the chassis as well.

[tedmich]

You might try to go the other way with temperature - try cold - like Coolzit. The best way to remove wax (actually desolve it on anything) is with the use of Freon. Good luck finding that today.

ebay!
1 12oz.can DuPont Ig-Lo Freon R-12 refrigerant:eBay Motors (item 170365052905 end time Aug-26-09 18:45:06 PDT)

[defaced]

I like how the person provides an out for anyone without a 609 form.

Buyer must comply with all local, state and federal laws and must email or fax me a copy of your EPA 609 Certificate or a signed statement certifying that this can is for resale only to a licensed certified tech.

"Oh, you just need a signed statement?... I'll be back in a second."

[olddawg]

How about setting the amp on its side or back while heating it with a heat gun/blow dryer. At the same time use a strong vaccumn cleaner with a very restricted nozzle. Make one from a shop vac, a piece of 1/2 inch tubing, and some duct tape.

[tedmich]

I like how the person provides an out for anyone without a 609 form.
"Oh, you just need a signed statement?... I'll be back in a second."

importing R12 from india or china is reportedly one of the most lucrative smuggling businesses, and almost risk free; once in the US its reported to be NOS and sold openly. I can't remember hearing about a huge shipment being interdicted...

[gbono]

Okay forget Freon - I believe most "green" citrus/turpin products remove wax as well. At least they remove wax from snowboards

[jrfrond]

I have to say that it is hard for me to believe that chemicially-inert paraffin wax is causing all of these problems in your amp. I've cleaned up a lot of funky spills in the last 30+ years in this industry, but wax doesn't have the mechanical capacity to pop components off of a PCB, unless they were barely hanging on to begin with. I believe you have an issue, but I just cannot wrap my head around it being solely related to the wax, unless it contained other contaminants, perhaps fragrance or such that might be partially conductive

Having said THAT, I have a gallon of precious 1,1,1-Trichloroethane that would wack the shit out of that wax in a hurry! Also, a hair dryer and some REAL compressed air (out of a hose, not a can) done several times would probably do the trick.

[Tom Phillips]

I used the method Chuck H described on an amp that had wax drip out of a transformer. It worked jwell. The "wax" was actually paraffin. It was mistakenly used by a less experienced (dumb) maker to encapsulate the transformers.
Tom

[TheTornOne]

Tried the credit card to get the bulk of the wax off, and a hair dryer and q-tips to get the rest off. Although painfully slow these worked pretty great. I had a few exposed traces from some abuse from the shop that originally tried to fix this and covered those with super glue.

Thanks for all of the great ideas!

[olddawg]

Tried the credit card to get the bulk of the wax off, and a hair dryer and q-tips to get the rest off. Although painfully slow these worked pretty great. I had a few exposed traces from some abuse from the shop that originally tried to fix this and covered those with super glue.

Thanks for all of the great ideas!

I guess super glue would work in a pinch. If it peals off just use some clear lacquer and a small art brush or clear fingernail polish. Personally, I find super glue inadequate for just about anything.