Silicone grease removal

Dawn...

Try isopropyl alcohol.

On Fri, 04 Jan 2008 03:52:55 GMT, with neither quill nor qualm, Jerry Wass quickly quoth:

Steam cleaning should fix you up quickly. Then an alcohol bath?

Why do you want to remove it? It does serve a purpose. It makes the terminal easier to install, seals out moisture, and keeps it from sticking to the plug over time.

Carl Boyd

I don't know Jerry, but I can tell you what doesn't work. Dish soap, alcohol, trico,, gasoline, brake cleaner, bug and tar remover and acetone. If you figure it out, let me know. Steve

I'm curious how silicone grease got on the wire ends in the first place. Anyway, VM&P Naptha or even paint thinner will dissolve silicone grease, and will swell the silicone rubber if too much is absorbed. The solvent will evaporate without much effect on the rubber. I'm probably not understanding your situation as the grease could just be wiped off, or is it stained or something?

And not the stuff most drug stores sell as rubbing alcohol which is labeled as 70% Isopropyl alcohol. They don't say what the other 30% might be - Maiden water? I got Isopropanol from a local shop which is labeled as 99% - see:

:-)} London, Canada

In airfield lighting, silicone grease is applied to wire insulation for the installation of neoprene insulation sleeves over termination of 5Kv cabling. The cables are now suitable for direct burial or water immersion. Gerry :-)} London, Canada

It depend on how clean you need the wires. Getting all the silicone grease off can be done using vapor degreasing with trich. But it isn't quick and easy. I would use lots of paper towels to get the wire ends fairly clean.

Dan

Can you please tell us why you need to remove the grease from ignition wires.

It was put there for a purpose and Ican see no valid reason to remove it unless you want to use the wire for some other purpose and if it is still Hi voltage work? Wots your real problem?

John G.

The only thing that dissolves silicone is chloroform. It is expensive, but works instantly.

I have used it to dissolve cured RTV silicone caulk and grease.

I was waiting for someone to say Freon or chloroform, because my next question was going to be where to get it. Those are the solvents that are used to disperse high-performance silicones in medical-equipment manufacture and they're both effective. But they're not usually easy to get. Where do you get yours, Ernie?

Depending on the carrier used for the silicone, easier-to-get toluene and xylene often work, and I've found both in paint stores. But my supply is probably 10 years old, and they may not be easy to get these days. I usually use xylene and it cuts most silicones pretty effectively. But if you can get chloroform, and if you follow safety precautions with it, that's probably the most available solvent that's nearly universal. It can kill you, but it works.

-- Ed Huntress

interesting discussion. ya learn something new every day. i gobbed up the trailer plug on my pick up truck w/ silicone grease (to keep out moisture, prevent corrosion). now i'm hoping doing that was ok. thing was though, careful as i was trying to be, that grease got all over, tiny spots. i found it was difficult to get off and once i got it on something it was impossible to make anything (electrical tape, etc.) stick to it. very pesky stuff. had no idea it required special solvents to get it off. i saw a "how it's made" thing on tv about building corvettes, they showed the paint shop, you had to enter it through a clean room. they specifically mentioned silicone as something that REALLY messes up their urethane paint jobs. environmental or ambient (can't think of the proper term, silicone that's out in the world) was something they were battling against. said even a microscopic amount can screw up a corvette's paint job. just interesting trivia. well, so, now that i got miniscule blobs of silicone grease all over my truck, and if i ever am trying to put some paint on it, now i'll know what to use to get it off. thanks.

b.w.

(this is embarrassing, once i worked in a place that made fiber reinforced polyester stuff. we had a fiberglass/silicone mold, the silicone wasn't properly "keyed" to the fiberglass and was flopping around inside the mold. it was ME who came up with the bright idea of using silicone caulk to glue the silicone to the fiberglass. that worked, more or less, but we didn't know that the areas where we gobbed the silicone would somehow permeate through the silicone mold material and retard the cure of the polyester. the polyester cured everywhere except where the silicone was applied to the fiberglass mold. it was a DISASTER and I was responsible for it. it was awful. must've been hundreds of dollars in materials and hundreds of dollars in labor. and that's not to mention cleaning the mold. i don't even know if it ever was successfully cleaned, maybe the silicone caulk destroyed the mold. oy.)

Maybe try some of the metal prep solvent sold for auto body silicone wax removal. Most auto paint suppliers have it, so should be easy to find, and if it does not work, at least you can use it for regular paint prep. I noticed Dawn Direct Foam dishwashing liquid seems to work pretty good at getting silicone spark plug grease off your hands. Seems like since 911 any chemicals not in general consumer use are harder to get....

Silicone is very strange stuff, chemically, and it causes all kinds of problems in industry. It's like a miracle that can bite you in the ass. As you mention below, it prevents the cure of some resin systems; as you say above, it is absolutely deadly under paint. If you use silicone wax to polish a car, your chances of ever getting a good paint job on it again are slim, say some experts.

The solvents Ernie and I are talking about are really desperate measures. I'm not enough of a chemist to know what they really do, whether they actually dissolve the silicone or dissolve the carriers that are mixed in commerical "silicone" products. As I understand it (vaguely) from reading about medical-device manufacture, chlorinated fluorocarbons, chloroform (and other trihalomethanes; don't ask me what that means, I only report ) and some related chemicals actually disperse the silicone itself. But I'm not sure about any of it.

Keep in mind that these solvents often dissolve the substrate that the silicone is on, along with the silicone. Again, I'm no chemist, but I've read over the years that chlorinated fluorocarbons and chloroform will penetrate almost any elastomer and make it swell, and weaken it. That means you don't want to use it on flexible insulated wiring, many types of gaskets, and so on. And even xylene will wreck some kinds of paint.

So, in many cases where you have to remove silicone, you're screwed. I've been told that trying to sand off paint that's been silicone-waxed to get a clean surface is an exercise in futility because it keeps spreading as you sand. The best solution is never to use the stuff unless you're sure you're never going to have to do a good gob of removing it. Silicone caulk is less of a problem than silicone grease, oil, or wax, but it can still be a problem.

Ouch! But now you're an expert on what not to do, having paid for an expensive education. d8-)

-- Ed Huntress

Hey, here's something interesting. Maybe things are better than they used to be:

"Dow Corning Cleaner and Surface Prep Solvent is effective at removing uncured silicone sealants, oils and greases, including removing any underlying residue. It can also soften many cured silicones, making them easier to remove. Scrape off the majority of the cured silicone, spray or wipe on Dow Corning Cleaner and Surface Prep Solvent, let soak, and wipe surface before it dries, repeating if necessary."

If anybody knows about removing commercial formulations of silicone, it ought to be Dow. I think I'd also call one of their techies to confirm that it's the right stuff for a particular job. In particular, I'd ask about pre-paint preparation if I needed something for that purpose. It may or may not be that thorough.

-- Ed Huntress

Citrus based cleaner.

Wes

We use a orange citrus based cleaner to clean up silicon fluid spills. That stuff in viscous fan drives. Nothing else seems to work.

Wes

On Sat, 5 Jan 2008 01:13:11 -0500, with neither quill nor qualm, "Ed Huntress" quickly quoth:

The automotive painter I used to work with would wipe down cars with naphtha before spraying. If he even suspected any silicones around, he'd also use xylene. Then he'd use fisheye killer (actually more silicone) in the paint for the rest of the car. He had one setup (gun, hose, paintpot specifically for that paint mixture. Nasty stuff. I only saw him use it twice in the 4 years I worked for Flynn's and he cussed all the way through both times. Dennis was a true artist and could match the angle of metalflake in paint to the Nth degree.