Conductive Grease or Gel

[Circuit Breaker]

Where can one find conductive grease or gel that can be used between metal parts to increase conductivity and keep out moisture? I'm working on my mobile antenna installation...mostly cleaning up all the connections and then adding a few new ones in an attempt to bring the match down. I checked Lowes but they didn't have anything.

['Doc]

I think I'd check with a few of the radio supply places. I know 'AES' carries some stuff like that, and I'm sure others do too. The only name I can think of off hand is 'NitroNox', or something close to that. Deals mainly with aluminum, but should work with other metals too, I'd think. (prevents oxidation) I've also used some copper based goop, sorry can't remember the name of that at all. None of this sort of stuff lasts for a very long time, weathers away sort of.
Depending on how/where those connections are, you might give a thought to some type of plastic coating. Lots of "if's", "ands", and "but's" with that idea so take it with some 'salt', lots of 'salt' maybe, whatever.
- 'Doc

One think to remember is that you don't want to get that goop everywhere.

[MoJo]

It's called Dielectric Gel and can be purchased by the tub at auto parts and RV supply stores.

Truck stops may carry it as well. It is great for trailer connections and antenna's.

[Circuit Breaker]

Okay, I'll check the auto parts store near me. I cleaned up the connections this morning but it didn't make any difference. I added a fourth wire from the mount to the frame and it brought the SWR down to 2:1...an improvement. These newer Toyota Tacoma trucks don't have metal beds...they're all a plastic composite material. I designed a mount that put the antenna 6" behind the cab and had it fabricated at a metal shop out of steel. I drilled all the holes I needed, spray painted it black and then used a Dremel and grinding wheel to remove the paint around the holes. I mounted it dead center behind the cab at the top edge of the bed. I had some old coax laying around and cut four lengths long enough to go from the mount to the frame. I stripped back enough of the vinyl jacket to expose the copper braid. Then I soldered lugs on to each end and made my connections...two lengths are connected to the bolts holding the mount on to the bed wall and two lengths are connected to the mount itself in the two corners against the bed. Since these beds are essentially plastic, they are flexible...although strong. To keep flexing down to a minimum at the top of the bed, Toyota installed three metal rails on the inside of the bed at the top. The piece behind the cab is probably four feet and the two pieces running the length of the bed are about 6 feet. The next thing I'm going to try doing to bring the match down is electrically connect all three of these pieces together and then connect the piece behind the cab to the mount itself. I'm hoping this will add more "ground plane" and bring the match down. Time will tell. I found that Lowes sells something similar to liquid electrical tape. I may get some of that as well and make sure all my connections are tight and then seal them.

[sparky17]

Dielectric grease is the opposite of conductive grease.

I did squirt a boatload of the stuff in every crevice of my antenna install, and it seems to be working alright. Right on the bottle it says 'battery terminals', so that was good enough for me.

[Foxhunter]

Yeah watch out that's absolutely true----dielectric grease IS AN INSULATOR and will reduce/prevent electrical contact which is the exact polar opposite of what most radio installations call for.

Dielectric grease is good for keeping moisture out of joints around the rim of a connection as in an automotive lightbulb or around the very edge of a sparkplug boot etc------but really is ill-advised to use on important antenna or supply conductor connections.

The same goes for some of you using the Loctite brand (red or blue) thread sealers on antenna threads or connections------the use of either of them decreases the electrical or antenna connection significantly. Just thought I'd mention it as I've seen many say they've used dielectric grease and Loctite in their installations. Good products, wrong application.

Circuit Breaker and anyone else truly interested in the proper product, what you want to use to dispel/seal out moisture AND INCREASE conductivity is basically the same product sold under two very old and reliable competing brand names:

Ideal Noalox
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Burndy Penetrox
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Either of these two above products will help increase conductivity at the joint of two similar or dissimilar metals, inhibit galvanic corrosion and weatherproof & seal the connection. Good stuff for sure and I have a bottle of each in my chemical cabinet. They are very familiar to electricians and commercial broadcast maintenance companies. A licensed broadcast engineer personally explained & recommended their use to me and are worth their weight in gold IMHO.