Wax Coating For Bolts To Prevent Rust

Question

After having replaced components such as tie rod ends etc the bolts and nut areas already have signs of rust starting on them, rusting further down the line. At times when these need to be undone to work/get to other components it is always a bit of a hassle.

Are there any sort of products available to 'coat' the exposed nut and bolt to prevent rusting? Something that wouldn't interfere with removing the bolt.

I was thinking of household candle wax (seems safe/coats well when hardened?) - melting/applying outdoors may be an issue though. Another though was to use vaseline.

Answer 1

The only way to ensure bolts/fixtures won't rust is to acquire bolts/fixtures which won't rust in the first place, such as stainless steel. Externally applied coatings will only last so long. Due to vibration and environmental conditions, coatings tend to come off at some point or get displaced. Just the nature of nature.

With that said, some types of products work better than others. I think the best type of product we can get which would prevent a fixture from rusting together would be anti-seize. Aluminum/nickel based anti-seize is most widely used for regular fixtures/bolts. Copper based is commonly used on exhaust and higher heat situations. Anti-seize won't protect the outside portion of the bolt forever. Just like everything else, it will tend to come off over time. Where it really makes a difference is in between the threads. It will help keep corrosion at bay there and make it so it'll be easier to get apart down the road. I use it liberally during assembly of most nuts and bolts.

Answer 2

After I de-rusted and repainted the undercarriage on my truck, I wanted to protect the exposed threads on various fasteners. Painting them was not an option, as that would make disassembly much too difficult.

So I used a product called Liquid Electrical Tape (available at home improvement stores) to protect the threads. I brushed on a coat of the white version, let it dry, then added a second coat. In the event that one needs to disassemble the fastener, all one has to do is rub it off with a wire brush.

It has been six years now and the coating is still intact. A few spots have turned a bit brown from rust, but I can say with certainty that the threads are still intact and serviceable.

Answer 3

I have had wonderful luck with simple clear automotive silicone. I installed new fog lights on my car 10 years ago and as a last step before I tightened everything up, I squeezed a bunch of clear silicone in and around the bolts (especially the threads), the heads and nuts. I took them off last year to upgrade them and the bolts and threads looked brand new. Everything came apart like a dream too.

The silicone itself is trivial to remove with a screw driver or small knife if you put a large amount on; and if a small amount, the socket/wrench just pushes the silicone out of the way and the bolts come undone without any trouble.

This will NOT work for anywhere that gets really warm (i.e. Exhaust areas), but for things that will get wet and salty (my area heavily salts the roads in winter), it should work fine. I don't know about heavy impact areas though, so it might happen that the silicone could be knocked off by gravel/rocks depending on your application.

It's a bit messy to apply, but no messier than paint, and no chance of overspray getting on painted surfaces.

Answer 4

There are spray coating products that leave a fairly thick waxy coating, like cosmoline, that are used in the auto industry as well as marine and military uses. This is one brand (no affiliation and no endorsement, just an example): Corrosion Suppressant Cosmoline Wax Metal Spray

Answer 5

By far the winning product in that category is paint.

But yes, there are greases you smear or spray on to prevent rust. Nearly any grease will help some (all you really need is to prevent contact with air), but there are some products made for that specific purpose. I use one made from lanolin, which is a surprisingly common base for preservation. It works... okay.

Of course, this will in no way address galvanic corrosion, so either have faith in the original material selection or get good at selecting bolt coatings yourself.

Answer 6

Owners of modern GM trucks know that protective frame wax is a thing, very similar to what you're thinking. GM specifically uses Daubert Nox-Rust X-121B aerosol for re-coating (they use a dip process at the factory).

The advantage of wax like this is that you can spray it over everything as it is removed by mineral spirits and other solvents if necessary. It is very easy to re-coat, just spray over and the new wax will melt into the old wax. The disadvantage is that abrasion, oil leaks and similar will take the wax off, so regular inspection and touch-up is needed.

It's the classic question of whether you want something sealed for "life" or something that will last longer but you have to maintain it.

Answer 7

I've got a 1973 series 3 landrover, and every bolt I touch gets a smear of Copper Eze which is very similar to the old-school "copperkote" product of decades gone by.

Of course this tends to make a mess near bolt-head flanges. But I've never had rust in areas where this copper-based stuff goes. Works well in wheel wells, which are a terrible place for corroded threads.

It is tenacious and resists being washed off by oils or water. The only thing that removes it is physically wiping, so it gets wiped off the underside of chassis rails by grass or gorse or other foliage.

https://www.repco.co.nz/oils-fluids/greases-lubricants/lubricants/penrite-copper-eze-anti-seize-grease-500g-ceze0005/p/A1199296