A72CUTLAS

I am attempting to paint my '72 Cutlass and don't want to fudge it up too bad. The only rust on the car is on the roof, and it's just some surface with a few spots that have pitted. I got something called Rust Encapsulator from Eastwood and had a question. My brother-in-law, who was a paint & body man 20 years ago, doesn't know anything about this "new-fangled" technology. So my question is, after sanding the roof down to bare metal, do I use the encapsulator first or do I just use Bondo. Also has anyone had experience with this product, whether from Eastwood or any other brand? Here are some pics; one where I've already grinded and one that still has the rattle-can primer I sprayed 7+yrs ago when the vinyl top rotted off.
Thanks for all replies.

geckonz08

Be careful. Try to place the encapsulator right on the spot.(s) ie try to avoid as much as possible getting the stuff on the good metal.( use an artist`s brush or one of those ear bud thingies.) One of these products which I used just said to paint/roll on and then wipe over afterwards with a sponge..This I did. The instructions were minimal and ambiguous. WIPE OVER is bad.,WASH THOROUGHLY with fresh, clean water and towel off is good.
In my case, after wiping with a sponge ,and 2 light coats of etch primer a very fine patina of rust "pushed through" over the area I sponged.(4 months ? later) Fortunately, I had just put the panel away and had not painted any further.
Cleanliness is godliness with this stuff.
Mike

geckonz08

Just another thought. Where you can wire that rust to bare , that has to be preferable.Etch primer , bondo and etc.
This rust stuff has been around for eons in one form or another as tannic acid , phosphoric acid but I have little experience with it other than above.
I am sure others will assist

MDchanic

Sandblast it (careful with the pressure) then acid etch it.

That rust down in those pits will crawl out and bite you later.

- Eric

69442C

Here's what you need to do and you won't need the rust encapsulator. Sorry, maybe you can return it. You need to get the rust out of the pits so either sandblast it as was mentioned (just cover everything well as it makes a mess and watch all trim and glass) or get a heavy duty wire brush that goes on a grinder. As a last resort, use a wire brush on your drill. Weld any holes closed or patch anything that is real bad but you appear to have very solid metal. After everything is cleaned, sanded and the rust is removed, you will need to spray the areas or the entire roof with a 2 part epoxy primer. Let the epoxy dry for a day or so and then scuff the epoxy by hand with 80 grit paper where you need to do your bondo work to fill the pits or work any dents. The purpose is to not remove the epoxy but rather give the bondo a little extra to grab on to. Finish your bondo work and then coat that areas with another coat of epoxy. If you re-coat the entire roof again, just make sure you sand the first application applied to the roof with 180 grit paper. Once the epoxy has dried again for a day, sand it with 180 and apply a 2 part urethane primer surfacer. If you need to do any block sanding, you will do it to this primer surfacer. Once you have the roof the way you want it and have applied the last coat of primer surfacer, you will wet sand the primer with 600 grit. From there you can apply a sealer and your finish paint. I would look to companies such as PPG, Dupont, Sikkens etc for quality products. Be prepared as these products are not cheap. Toss the rattle can primers as they aren't that good and won't be compatible with the products mentioned previously. Good luck with your car.

Chumley

I used Rust Encapsulator several years ago on the rear suspension of my 3/4ton Chevy truck. I just wire brushed all the loose stuff off, then brushed on the encapsulator and then chassis black on top of that. I also used it on the floor inside the cab for some spot rust places. I think it's a good product if you don't have the tools, time, and money to go bare metal and prep route.

Coltonis

I haven't used Rust Encapsulator, but I have used Por-15 which is its main competitor and if the two are anything alike:

Imho I would not use a "Rust" formulation paint on the large smooth body sheet metal areas. (Well maybe if it was just a band-aid quick fix coat until I could do it right, but even then I might prefer something that sands off better.) I know from experience that POR-15 tends to dry thick and not lay down evenly on smooth surfaces not to mention it sands like *****. (Its great on rough casted type surfaces, though.)

69442C's suggestion is what I would consider to be the "full blown" approach. If you are doing the rest of the body with paint at the same time its probably the best approach.

If you are just trying to stop the rust in that area and not going to paint everything these would be my methods in order of preference:

Option 1.
Ligthly sand blast then epoxy primer - simple if u have the equipment.

Option 2.
Wire-Wheel the shiz out of the pits.
Then use Phosphoric acid and Zinc Phosphate to prep the metal
(POR Metal-Ready is both chems in 1 solution or PPG DX579 is Phosphoric acid and DX520 is Zinc Phosphate) Those two chems are a very common process used to stop metal from oxidizing - cause they work. THEN you still need to epoxy primer it.

I usually end up doing Option 2. on my stuff since I don't have the equip to sand blast. Flip a coin on whether or not to put the bondo above the epoxy or below it. PPG says above - Most bondo makers say below.

(PS BONDO brand I've read is not very well regarded by most body work guys -Evercoat tends to be favored)

A72CUTLAS

Yeah that sand/soda blasting would be nice if I had the equipment. At least my arms & shoulders wouldn't be sore.

After posting this I called a paint store and the counter dude reccomended Metal-Ready, so I'm gonna take it up there so he can give me some specific advice RE: this. I appreciate all the replies and advice. I'll be back if there are any more hurdles.
Thanks again

oldsguybry

what are some of the instances where you would need to block sand , not sure quite what that means , and do you sand the 2 part urethane primer inbetween coats also ? if so what grit do you use ? as far as wet sanding with the 600 grit , how long do you let urethane primer dry before you wet sand with 600 grit ? im kinda in the same situation where I need just a few more answers to get moving on my project , especially with the nice weather on its way....thanks in advance also...

Bry

oldsguybry

my apologies A72Cutlass , did not mean to butt into your thread , sometimes its hard to get answers on certain things and one becomes desperate...lol...marine clean , then metal ready , then POR-15 ....was the instructions i remember....I did an area on my frame (only one coat) and its held up for a few years now.

69442C

Since the question was asked, let me give a little info and I hope I don't cause A72Cutlass any issues since this has taken a little different direction. If so, let us know and we'll get Oldsguybry to post a separate thread.
Block sanding is where a surface is sanded using a flat block or sanding block to get the surface as flat as possible. Usually this is done in combination with a "guide coat" or I just lightly spray a darker lacquer type paint from a rattle can. When you block sand an area, the darker color will highlight any low or high areas as these will retain the dark color or will lose the dark paint first. You can continue to sand until the dark paint is removed uniformly for the area. Just be sure to get a long sanding block for long areas and resist the urge to only sand in one particular area. Blocking is done over dent repairs to make sure everything is straight and also on non repaired panels as factory steetmetal can have little waves in it. It takes a little practice and is a fair amount of work.
Block sanding is done to primers that are able to provide a high film build, meaning you can build up several mils of thickness to give you something to work with. I use PPG products and DPS3055 is the primer surfacer I use for this. Be prepared to spend over $250/gallon with the hardner and reducers. Sikkens also make a nice product and theirs will run over $300/gallon for everything. If the metal is ready to go, I will apply an epoxy primer such as a PPG DP series (there are varios colors and the number indicates the color...DP90 is black, DP50 is gray) and I allow that to dry for 30-45 minutes assuming a warm temperature and you can then spray the primer surfacer directly over the DP epoxy without sanding the DP. If the DP epxoy is allowed to sit more than 24 hours it needs to be sanded before you spray anything on it. The DPS primers are reduced differently depending on if you want high build or not. I will usually let that sit and air dry for a couple of days before blocking. If you want to apply more of the primer surfacer, you need to sand everything and I would use 180 grit to do this. Also, use 180 grit for your block sanding. It may take several block sandings to get things where you want. Once the final coat of primer is applied, you need to use a much finer paper such as 600 grit and this is best done with water and this wet type 600 paper. Apply the same guide coat to allow you to see your progress. When you wash off the panel with water, you will be able to see if it is straight or if it still has waves in it. If it's OK, it's ready for paint which involves a sealer, color and clear.... assuming a base coat clear coat is used. Otherwise it's sealer and color. It's a detailed process that takes a lot of work and is expensive. But this is the process for a quality paint job. Good luck. There are videos available that show this so they will be helpful if you wanted to get one. I think Eastwood sells some of these but I'm not 100% certain.

A72CUTLAS

No, dude that was AWESOME!

If you haven't already guessed, this is my first paint job, and I'll be doing it in my garage so any and all info is appreciated. And even though my brother-in-law is "teaching me", he's one of those guys that did this(past tense) for many years and and can't/won't explain each process as you just did.

So no, if you'd like to offer any other suggestions, lessons, or info please, let 'em flow!!

Rickman48

I'm kind of 'old school', and managed a few body shops in the '80's - the days of 'blow-off' paint and 'fist-size rust spots, in the middle of nowhere, for no reason'!
There's a product called 'metal prep' that we used on all bare metal, including rust,
[after grinding it out] that kills the rust and accepts primer right on top of it!
Mix with water[?] wipe on, and let it dry - done and inexpensive!
In a production shop, we'd then apply bondo fiberglass gel, with hardener, sand, primer and paint!
I never had a comeback, in 10 years, doing it that way!

MDchanic

Basically the same as the POR MetalReady (where do you think POR got the name ?). MetalPrep is a phosphoric acid type solution. I don't know whether it contains any other acids, but I've used both, and they always seemed about the same to me. Sorta like chocolate and vanilla.

- Eric

69442C

A72Cutlas (got it right this time) the best advice I can give is to remember that paint work is 90% prep, most dirt in the new paint comes from the car itself and to find someone who has done this work and can guide you and look at your progress. Maybe you can find a "new" brother-in-law who will be more helpful. Read a few books and get a video or two. Or better yet, look into a class at your local schools to see if they offer one on painting. A lot of painting is technique and "feel" and those are hard to teach without being there to supervise. If you have an old panel around, practice on it. Once you understand how to prep the panel and mix the paint, you just need to get a feel for how to apply it. It's either going to be too dry, just right, or too wet which means it will run. Some errors can be fixed with wet sanding; others can't. Wash the crap out of the car and spray water everywhere you can, including under the car to get rid of as much dirt as possible. Do this a few days before you paint so the water dries completely. Good luck and let us know how it works out.

stan 65 cutlass

when using metal ready(por) does it need to be washed off with water? or can it be sprayed into doors and quarterpanels then por when dry? i dont realy want to get my car all wet before sealing it up.

Bluevista

Yes you have to wash it off, it's the same as any other conversion coating except that it costs about ten times as much.

The old timers used vinegar to etch metal for paint, gutter guys used it to prep the galvanized steel half rounds before they primed them, I'm proud to say I was one of them.

Nilsson

I used Purple Power De-ruster, coverts rust and once it drys it is ready for primer. Worked great for me and no rinsing. Get it at Auto Zone and the like and it is cheap compared to others.

Coltonis

POR MetalReady is simply Phosphoric acid and Zinc Phosphate in a solution (ie with water). I have read that its not the "best" to have the two chemicals in the same solution, but clearly it works "well enough" and it probably simplifies things from a product sales stand point.

The way that those two chemicals work is the Phosphoric Acid attacks the metal allowing rust to be washed off the surface and small micro-pits to form which should help with paint adhesion. (Read: Cleaner/Etchant)

The Zinc Phosphate is actually the more important of the two chemicals though. See when it is applied it creates a thin chemical film of Zinc on the metal surface similar to metal plating. The Zinc acts as a buffer. It is much more resistant to oxidation and the underlying metal (steel/iron) is then sealed off from the catalyst of the rust process (oxygen) by the Zinc layer. (Read: Stops Rust Process)

The film however is VERY thin so it needs to be coated shortly after its applied or every nick, scratch, rub, and oily finger print is going to remove the Zinc layer and expose the base metal which will then start to rust. Hence it still needs to be primed with some sort of paint to protect first the Zinc coating and ultimately the base metal.
(Read: Prolongs Protection Indefinately)

The Zinc Phosphate would probably be OK (if not do better) to let dry on the metal; the Phophoric Acid on the other hand ABSOLUTELY needs to be thoroughly rinsed off with water afterwards to neutralize the metal surface. Since MetalReady has both chemicals in the solution it definitely needs to be rinsed off after application too.

I think that is the main reason behind the opinions that it is better to use the two chemicals separately.

Coltonis

PS In addition to that Purple Power De-Ruster Nilsson mentioned I have also found Jasco makes a much cheaper Metal Prep product that is sold in most HD,Lowes,ACE, etc. - But both of those products only contain the Phosphoric acid. So you are just removing the rust and etching the metal. It would be up to the primer used to cut off the oxygen/moisture contact with the base metal surface and prevent rust from re-forming. I have yet to find a cheaper source for Zinc Phosphate on its own. Last time I looked the same volume of MetalReady works out to about the same price as the two PPG products so I would go with the PPG stuff, but I found a PPG store two minutes from my house, so thats just me

stan 65 cutlass

i already bought the metalready,$20 for the spray bottle, i dont want to mess up the por 15, so im sticking with the same company, i guess its rinse o rama, and let dry.

oldsguybry

yea , that metalready is some nasty stuff , but just like you said , let majority of surface dry after application , and then rinse off the excess.....it turns white , and soon afterwords will start to rust , so i accelerated the dry time by pulling car out in the hot sun. Then pulled it back into garage and applied POR-15....no rust ever came back in any of the areas that i put some on , but i did not read the instructions as well as i should of , and only put one coat on , but still held up.

A72CUTLAS

OK... I've done some reading up on metal ready & POR15. It seems that it is meant to be used on frames and undercoating, not finish panels. Am I off base here? What I've learned so far is that a good paint job is 90% prep, but doesn't the quality of the prep materials just as important?
Now don't worry, I don't have any delusions about my first paint job being show-quality, but I do want it to look good enough that people will ask who painted it so I can say "I DID!!".

oldsguybry

you are correct , only use on frame and like parts.....i used it in the pockets in the trunk , and along the wheelwells , also on the inside of the fender behind the support.......these were the only areas I used POR-15 other than the frame , because of some small holes that were appearing in those areas....there are other products like from Eastwood that are suppose to be just as good as POR and easier to use also.

A72CUTLAS

Right, like the Rust Encapsulator. After reading up on the POR 15 stuff I just decided to use what I already had. BTW, I bought this stuff to restore a front disc system I'd bought(still haven't gotten around to it yet.) What did was take half of the roof down to bare metal with a cleaning disk, which was able to get the majority of the rust out of the pits. I then sprayed the RE which is a flat black color, kinda reminds you of the suede bombs back in the day. Anyway, that next morning was very dewy(?) so I didn't know what to expect. What I did see reminded me of that commercial where they waxed one half of a car and not the other. The side that I hadn't touched yet had big droplets of dew while the "encapsulated" side had just a few small droplets of water. I don't know if it means anything but I poured some water on it to see if it was BS but the same thing happened, water sat on untouched side but rolled of the worked side. I didn't think to take pics but I will in the AM.
Still open to all advice or replies.
Thanks

Nilsson

FYI, phosphoric acid is also an ingredient used in soda pop.