Sand papper cleaning Nos resistors

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RockinRocket
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Sand papper cleaning Nos resistors

Post by RockinRocket »

I have some phires resistors and they are pretty nasty. So I sandpapered them and then wiped them off. Is this a ok method to use? I don't have any thing else that worked
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xtian
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Re: Sand papper cleaning Nos resistors

Post by xtian »

A solvent like naphtha ...or even soap and water would be better. Are you talking about the leads or the resistor package itself?
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jelle
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Re: Sand papper cleaning Nos resistors

Post by jelle »

I do the same with the leads of vintage resistors that have oxidized a lot. Fine grit sand paper or I use a fiber glass pen like this one:
http://www.amazon.com/SE-7616SB-Fibergl ... B003NHDITW
gingertube
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Re: Sand papper cleaning Nos resistors

Post by gingertube »

Old Techo's trick
For cleaning off PCB tracks before loading and cleaning up component leads, use an old fashioned ink eraser.
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JazzGuitarGimp
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Re: Sand papper cleaning Nos resistors

Post by JazzGuitarGimp »

I drag an exacto knife blade along the leads where I intent to solder. One hand rotates the resistor while the other scrapes up and down the lead.
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David Root
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Re: Sand papper cleaning Nos resistors

Post by David Root »

Those old Pihers all seem to have dried lubricant of some kind on the leads. I use 80 grit sandpaper on them, seems to work well. Sometimes I forget to do that but no bad solder joints, I guess the solder flux takes care of the old crap.
RockinRocket
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Re: Sand papper cleaning Nos resistors

Post by RockinRocket »

Oh good. The leads were pretty nasty and all I had was sandpaper. Glad to hear you haven't gotten a bad solder joint from sandpaper
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Leo_Gnardo
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Re: Sand papper cleaning Nos resistors

Post by Leo_Gnardo »

I just scrub the leads with the serrated end of needle nose pliers prior to soldering, scare up some clean looking metal.

Scotch-brite or fine sandpaper 400 or 600 grit would work fine too.

80-grit? Crikeys that's what I use to knock old paint off the house shingles, must be some awful gunk on resistor leads to need that :shock:. But if that's what it takes ;) go with it.
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rp
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Re: Sand papper cleaning Nos resistors

Post by rp »

0000 steel wool does it for me, soft and wraps nice around, nothing could work better. I always have a small wad in my e-toolbox.
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JMFahey
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Re: Sand papper cleaning Nos resistors

Post by JMFahey »

Also steel wool here, removes just the grit (softer or crumblier) removing very little metal, if any.

Of course in a pinch burnishing leads up/down with the serrated end of pliers works too, have also tried wet/dry sandpaper or emery cloth ... but around 400 grit; 250 already leaves visible scratches ... can't even imagine using 80 grit though :shock: , what I use for a last sanding over before tolexing cabinets :D
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ToneMerc
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Re: Sand papper cleaning Nos resistors

Post by ToneMerc »

RockinRocket wrote:I have some phires resistors and they are pretty nasty. So I sandpapered them and then wiped them off. Is this a ok method to use? I don't have any thing else that worked
I first wipe them down with 99.8% alky to remove as much of the 30-50 year old tape adhesive residue and oxidation as possible. Then, I lightly burnish the leads with either 400 or 600 grit, usually 600 though to start. Next I finish them off with a few light hits of 1000 grit and wipe them down a final time with the alky. I use the same procedure for all the old caps as well.

If you see copper you have gone too far.

TM
RockinRocket
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Re: Sand papper cleaning Nos resistors

Post by RockinRocket »

Leo_Gnardo wrote:
Scotch-brite or fine sandpaper 400 or 600 grit would work fine too.
Scotch brite didn't do jack for these nasty resistors. I did fid a way to get needle nose pliers to work.

Tone Merc - If copper does appear is that bad to solder too? Not that I have done so just interested.
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Colossal
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Re: Sand papper cleaning Nos resistors

Post by Colossal »

I use 0000 steel wool as well. Works great.
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Re: Sand papper cleaning Nos resistors

Post by Garthhog »

Red Ruby Eraser. I have fixed A LOT of problems with this indispensable tool.
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rp
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Re: Sand papper cleaning Nos resistors

Post by rp »

For any e-gunk I use acetone, wet a piece of 0000 and it should clean up anything, q-tips and acetone good-bye flux residue. Watch the acetone around anything painted or lacquered.
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