Cleaning Oxide off Transistor leads?

Zero Cool

Paid Member
2004-09-20 6:10 am
I am rebuilding a piece of gear that i noticed all the transistor legs have severe oxide growth. look like little fuzzy bug legs. If i gently scrap the legs the oxide comes right off.

Anyone have any experience cleaning transistors as such???

I was thinking maybe some Tarn-X might work with some cramolin. or is there a product for this?? I thought i saw something called Deoxit???

Whats best.

Tarn-X contains sulfuric acid (or was it hydrochloric?) Can't say I care for that stuff.

I've seen the grunge you're talking about, and I've sprayed the board with Windex, and scrubbed it (and the transistor leads) with an old toothbrush. All the grunge came off. Blasted it with compressed air, and it all looked great.


2002-12-23 11:22 pm

Deoxit is excellent to use in the right application, but it isn't really intended for dealing with such heavy 'growth' of contaminants as you describe here.

If it was me, I would simply scrape off the excessive build-up, and then maybe use something like Deoxit afterwards to get the last of this unwanted mess off.

If parts are off the board--0000 steel wool. And since some dunderhead always feels obliged to have a hissy fit because steel is conductive, I always have to add that you do this over a trash can off to one side. If you want to go a step further, use isopropyl alcohol to clean the part afterwards. (Actually, I use acetone or lacquer thinner, but don't get any on film caps. Alcohol is cheaper and safer, just not as good at cleaning.)
Now, as to cleaning the stuff while it's still on the board...upper rack of dishwasher, then allow to dry thoroughly before putting back into service. No, I'm not kidding.



2004-09-09 11:34 pm
GRollins said:

Now, as to cleaning the stuff while it's still on the board...upper rack of dishwasher, then allow to dry thoroughly before putting back into service. No, I'm not kidding.


Years ago I worked at a place that cleaned water soluble flux from boards with a standard dishwasher. The heating elements were disconnected and only cold water was used.


2006-12-28 12:19 am
that oxide fuzz you are talking about comes in different forms, depending on the base metal, usually it's green from the copper in the wires or component leads. windex is the best way to get it off, the dishwasher rack idea sounds even better. the corrosion you describes comes from salt air, or exposure to some kind of salt and moisture. since the salt is water soluble, the dishwasher method should be the best. the only problem with using the dishwasher is that water could be difficult to dry out of any transformers or relays on the board, so make sure you remove transformers and relays first.


2008-12-06 3:17 am
I just Fixed another problem with Tarn-x, every time I have a noisey transistor or IC in old audio amps and tape decks, some have black on leads some don't but after taking out and dunking in Tarn-x for 5 or so minutes and rinsing in water and drying, they work like new, No more noise. Today it was a Pioneer 904 reel to reel and the second opamp after the play head, It was even feeding back to the Jfet head switch's ahead of it.Thought it was them at first. An other tech where I work taught me this years ago and it works all the time to get the black off leads of old semiconductors. Also the first cap after the play head is always leaky and the coupling caps a tip I found out on my own. That fixes poor frequency response. The owner calls me Mr CAP cause of all the Caps I replace - but that to makes these old units work like new. I Just love fixing old stuff.
Mr Bill