Rust Catalyzing Primer

[Mr Blotto]

Is there a certain brand that is better than others?

Is Locktite Extent the same stuff? http://www.hectorshardware.biz/shop/pro ... ku=782386&

Thanks!

[mattg]

I also need to pick up some rust catalyzing primer - I was looking at zero rust spray primer but have yet to make the order.

[Runamuck Bus]

I have been using RustMort. It is a 'rust converter' product that is applied to a prepared 'rusty' surface. Instructions say to remove loose rust; the guy that recommended the product to me said to leave the surface slightly rusty. I apply with a paint brush. It is thin and watery and covers fast. The surface blackens as the product dries. It should be wiped clean with a damp cloth before covering. It is not a primer, but it can be primed. I have primered and have undercoated several areas and so far - OK (but I'm only talking a couple of months not exposed to the elements). Lots of information is available on the net. I might have some pics, but they are not here now and I would have to look.

[bretski]

I have a can of the Locktite stuff that I've used in a few spots. Works fine. Having tried a few brands, I can't say I've seen a whole lot of difference between them...

[Amskeptic]

I use aerosol spray to drive it in to the crevasses where it does great work. An air compressor with a nozzle helps treat the internal surfaces. The 16 years I've gotten out of it has been gratifying, but this last rain-soaked east coast itinerary has finally shown signs of breaching, probably due to the increasing body/chassis flex after a half million miles of loosening spot weld seams. No brand loyalty from me, whatever works, I say.
Colin

[Mr Blotto]

probably due to the increasing body/chassis flex after a half million miles of loosening spot weld seams.

Sounds like you need...uh....I don't know....a bus with 38k on it!!!

[upnorthman]

So I picked up some self etching primer and did a little searching. The problem that I have with the stuff I just bought is that it cost me $15. This may have to go back for something cheaper. I found a discussion on it and:

When doing major or even minor work on older cars your going to run into rust. The steel that is your car wants to turn itself back into the puffy red iron oxide that it was when it was mined. Whether you’re sanding, sand blasting or chemical striping to get rid of the paint and getting down to the metal the first thing you need to apply to the steel is self etching primer.

Self-etching primer is composed of an acid and zinc. The acid, usually phosphoric acid, forces the zinc down into the top couple of molecules of the steel. Chemically impregnating the steel like this cannot reverse the rust but it can stop in from getting worse. So it’s important that you get all of the scaly rust off.Self etching primers such as Dupont Variprime do prevent corrosion in the short term but,if left long enough will allow corrosion to form.Some primers are pourous and do allow moisture to penetrate if left alone.Self etching primers are meant as a ground coat.They etch into the steel to allow all subsequent top coats to have something to adhere to.Cheap primer is good for areas that you are working on and cant top coat right away,dont use them for final coating a car before you paint.As stated above use a good urethane primer at the final stage.If you can, use a good sealer over it before final colors are applied.This will prevent bleed through and blemishes(blushing) of top caots.You can do without sealer if money/time dont permit just make sure the surface is uniform(coverage wise)and DRY.Hope this helps Good luck.

Wipe the surface with wax and grease remover to get it clean enough so nothing interferes i.e. fingerprints. The self-etching primer is usually gray or olive drab gray but the color is just there to show you where you’ve put it on and it is very thin and one thin coat is enough. Putting more of the primer won’t make it work better. You can apply it over paint or bondo but it is only effective on bare metal. You can apply your high build primer or body filler over the self-etching primer but be careful it is not a finished product by it self.

In other words you can’t apply it and then push the car back outside, it has to have a sealed surface over it, water will reverse the reaction and will pull the zinc back out.

Self-etching primer comes as two parts or ready to spray and also comes in aerosol.

I use it when ever I see bare metal or if I’m putting one metal against another. For instance steel screws in aluminum or on welds.

Colin, you were talking about spraying it into cavities for protection with compressed air. It looks like we should also spray in something on top of the primer especially in the cavities, yes? An additional primer/paint on top of the catalyzing/etching primer would seal it up good, yes? Is catalyzing the same thing as etching?

One group was talking about putting a urethane primer on top of it.

Self etching primers such as Dupont Variprime do prevent corrosion in the short term but,if left long enough will allow corrosion to form.Some primers are pourous and do allow moisture to penetrate if left alone.Self etching primers are meant as a ground coat.They etch into the steel to allow all subsequent top coats to have something to adhere to.Cheap primer is good for areas that you are working on and cant top coat right away,dont use them for final coating a car before you paint.As stated above use a good urethane primer at the final stage.If you can, use a good sealer over it before final colors are applied.This will prevent bleed through and blemishes(blushing) of top caots.You can do without sealer if money/time dont permit just make sure the surface is uniform(coverage wise)and DRY.Hope this helps Good luck.

[Amskeptic]

Colin, you were talking about spraying it into cavities for protection with compressed air. It looks like we should also spray in something on top of the primer especially in the cavities, yes? An additional primer/paint on top of the catalyzing/etching primer would seal it up good, yes? Is catalyzing the same thing as etching?

I follow the primer with topcoat (or black engine enamel under the car), and follow that with rubberized undercoat if doing the chassis. I do NOT spray rubberized undercoat into body cavities or up drain holes. I want them to drain cleanly and quickly.

The FLAPS aerosol rust catalyzing primer (muiatic acid based) does not need paint over it if it is not exposed to sunlight or direct road splash. The etching primers (zinc), if they need a topcoat, follow with a topcoat. It boils down to following the directions

[upnorthman]

Thanks,
I can't help but over analyzing things I want to know all the correct options available. It is something I can not help, esp. when it applies to the bus.

[Redcoat]

If you can find it, Fluid Film is what i've used for the past 18 years on my various cars. Both on the salt treated roads of southern England and New England: http://www.eurekafluidfilm.com/

Works a treat!

[chitwnvw]

gemplers.com has stuff used on farming equipment. You can get it in aerosol or in a paintable liguid goo. Both have done the job for me with out breaking the bank.

http://www.gemplers.com/product/RCQ/Rus ... -One-Quart

http://www.gemplers.com/product/127787/ ... -Converter