Best rust treatment?

I'm after people's opinions on which rust treatment they prefer to use and have had experience using, I've used a treatment which hoes onto bare metal after you clean the affected area up best you can which is made by Wurth but have just ran out. Ready to buy some more now and I've heard good things about Por 15 but I'm sure people on here will have used many different products. Cheers

Bilt Hamber Hydrate 80 but I think its all the same thing anyway? Just slight variations in viscosity from different manufacturers which makes it behave slightly different when applied etc.

paul_c said

Bilt Hamber Hydrate 80 but I think its all the same thing anyway? Just slight variations in viscosity from different manufacturers which makes it behave slightly different when applied etc.

So is that hydrate 80 thick or quite runny? The Wurth stuff I had went quick a long way as it was similar consistency to water

Runny

Who's actually owned a car long enough to find out these potions actually work?
Once rust is ingrained into metal all you can do is cut it out if your in for the long term.
A rust potion will just slow down the oxidizing process by starving it of oxygen and moisture.
I treated the shot blasted underside of my car with epoxy mastic 121 4 years ago. Unless I remove it then I have no clue as to whether its actually doing its job.

This is true, I'm using it as a precaution really on bare metal which I've cleaned back and had sandblasted. 

Bilt Hamber products always seem to do well in comparison tests - Practical Classics mag did a big test about a year ago on rust treatments.

The Practical classics tests had http://www.rust.co.uk/  as there best on test. They all say they do the job and they also baffle you with science.

I wonder what is the criteria of the test?

I'm sure its not as simple as Just throwing a couple of buckets of salty water at some freshly painted steel but there are many factors involved.

How long does the test take?
How long ago were the potions applied that they're testing?
Does it take into consideration the changing of the seasons, flexing chassis. already present corrosion ….the list goes on.

I'm very sceptical of such claims by manufacturers of some of these products.
Don't even get me started on diesel injector / fuel system cleaners!! "Just pour it in and it'll be like a new engine!"

I was recommended Bilt hamber Deox Gel. Again I don't know if it works or not. There is a good video on YouTube where a guy puts some rusty steel in some Bilt Hamber liquid and comes out like a new piece of steel!

Deox Gel and Deox C are rust removers. I have used both and they work well. Hydrate is a rust converter (like Kurust), that turns rust into an inert black substance. If you have already got back to bare metal, then it isn't rust treatment you need, but a good quality coating system, which you choose will depend on whether it is bodywork, chassis, or components that need protection. I have used Bilt Hamber spray primer and also their epoxy mastic. Other brands like those sold by Frost also come out well in tests.

One Practical Classics test involved a Ford (Mondeo I think) being stripped and coated in stripes of about 15 different products and then being left out for a year.

Don't know if I'm missing something but if you can get a rust remover like Deox gel, why would you want a rust converter?

The Wurth stuff I've had for a while now goes on purple ish colour and changes to a black over an affected area. I used this on my beetle and seemed to have sorted the job out. I use a knotted wire wheel on my grinder to treat an area that isn't rotten but has started to get into the metal then if it seems to have sorted it treat it with the rust treatment before zinc primer. These areas are on the bodywork which I'm taking about personally.

Hydrate 80 is for surface corrosion where you can clean it up, for example with a wire brush on a grinder, but only so far. The wire brush removes most of the rusty metal but it remains slightly rough instead of smooth shiny metal and in the pits there's still mild corrosion. Its the same chemical as the Wurth stuff, and chemically converts the rust to a stable coating.

Its ideal for areas where you'd not really want to grind the surface down to a smooth finish because doing so will make it thinner and weaken it. Then you're into cutting out the metal and welding in new sections - a much bigger job. So its not a "perfect" solution but its much easier and realistically can be done on areas you'd otherwise leave or commit to a full restoration job.

If your metal area is genuinely 100% rust free then there's no need to use it, you could use a decent etch primer as the first coat, followed by primer, paint.

Yes that's kind of what I mean the little bits under the under seal around arches and on the floor pan which maybe have trapped moisture or slight ingress of water maybe due to stone hips over the years which have cleaned up with the wire wheel I would rather be safe than sorry and have to cut a section of the floor away after a lengthy full resto. 

I've said it before and I'll say it again , kill the tin worm cut it out and replace it end of story !!

golfman16 said

I've said it before and I'll say it again , kill the tin worm cut it out and replace it end of story !!

Not always as straight forward as that though, the bracket with the bolts on for the axle mount for example is thick metal which cleans up and is treatable rather than trying to recreate a panel with sheet steel to replicate the original which will be perfectly fine once cleaned back and treat. Fair enough thin panels which is easy enough to chop and and create a straight forward replacement piece or buy the repair panel I totally agree

golfman16 said

I've said it before and I'll say it again , kill the tin worm cut it out and replace it end of story !!

A lot depends on the situation. Welding, done well, is still somewhat of a disruptive process and would require a lot of tidying of the welded joint area to guarantee no corrosion in the (near) future. And some joins are difficult to do in a DIY environment, for example sills and many other panels are spot welded during the construction of a bodyshell and later on, its simply not possible to get the electrodes into the same place, notwithstanding the price of spot welding gear. So some kind of compromise is normally involved in any welded repair.

A good example would be the rear bodywork lip of a convertible, where the hood tucks in. This often rusts but can remain structurally sound with some surface corrosion. Cleaning up and coating with Hydrate 80 will enhance longevity and spare stripping down a lot of trim in the boot area and either obtaining (very expensive) or making up (time consuming) repair sections.