Restoring a Rusted Roof

[Gregski]

My 68 coupe had a vinyl roof. One of the previous owners ripped off the vynil to allow it to breath and minimize the water damage. The vehicle sat outside in northern California but the roof still rusted. I would like to share my attempts with you on how to remove the rust yourself.

My budget is $100 bucks a month to spend on the car, but that is to bring back the entire car to life, so please don't suggest I save the money for a couple of months/years and take it to a "reputable" shop to have it done. The point is to do it yourself and eventually paint it instead of vinaling it all over again. I do not have an air compressor, so I can't media blast it.

Your feedback and advice is very much appreciated as I have not done this before.

[Gregski]

So first thing I decided to try was sand paper / sand sponges and handrollics and elbow grease. From Home Depot I purchased a pack of three sheets of 320 grit 9 inch by 11 inch sand paper and one Ultra Fine (grit unspecified) sanding sponge. Decided to go with that because of what I read on the internet, and I knew I could always go coarser but didn't want to start off with some media that would put holes in my roof, know what I mean Vern?

My buddy came over to help me fight the rust, and after about an hour of working said: "You're better off using paper towels!" meaning the grit is too fine on what we have. It was around lunch time anyways, so after picking up some tacos at Carollina's we went across the street to AutoZone.

Armed ourselves with some 9 x 11 inch 120 grit paper to cut up for our sanding block, and three different sponges: Green 60 grit, Red 100 grit, and Yellow 320 grit. The sponges are pretty cool if you haven't tried them already you might wanna, they conform to the shape of what you are sending fairly well.

Rust is a b-a-s-t-a-r-d, very difficult to get rid off by hand, maybe it could be done but I don't have months to spend on this doing it by hand plus it would take hundreds of dollars in media. After about 6 hours spent with these products wet sanding I think it is time to try some chemicals.

Using images off the web for the sponges because my camera didn't wanna focus on them when I took my pictures. Other's are authentic, LOL.

[Gregski]

Well before following some of this sound advice, here's what we've tried. Vinegar, which did two things. First it evaporated, second it stunk up the garage, and didn't do squat in terms of rust removal.

[Gregski]

Next up was RUST-OLEUM Rust Stripper, a bit better than the vinegar but still as effective as sucking a titty through a sweater. Instructions said leave it on for 10 minutes. We gave it a bit more time, but all it did was expose some tiny bare spots here and there. It could be done, but we didn't have 50 gallons of this stuff. We only tried it on half the roof so we could compare the results to the sand paper side.







[IMG]http://www.gregandsandy.com/mustang
/pics/DSCN5028.jpg[/IMG]

[Gregski]

Since there was no glass I removed the rear window molding/trim. It is held in place with three screws on either side, diver / passenger and six trim clips on top. I was able to pull the top trim off by hand. The bottom trim came out easily, in 10 inch strips all broken up.

I learned that the headliner is tucked in under the molding / trim, so it must be installed before a new window goes in. I bet same goes for the windshield.

[Gregski]

So I am getting braver, my abrasives are getting coarser now using 60 grit sandpaper, and added electrical tools, a palm sander, a 1/3 HP hand drill, and a 4 inch angle grinder and even tried some wire wheels since I already owned all these items. Went out and bought a gallon of Klean-Strip Phosphoric Prep & Etch at Home Depot for $14.97 and some Dust Masks for $1.97.

[Gregski]

The 60 grit sandpaper on the palm sander seems to be working the best so far on the big flat surfaces.

I used the wire brushes and the angle grinder sand discs in the tight spots like the rain gutters above the doors, after removing the chrome trim. When I used the brushes on the flat surface it seemed like it was scratching the metal, maybe exposing prior scratches, I'm not sure.

The 3M Light Rust and Paint Remover disc wasn't worth it, it bends and is probably good for just that light rust removal, LOL.

[Gregski]

I was able to remove the chrome trim above the doors. Some suggested using the special tool, others a bottle opener. Naturally the type of bottle opener that I have is not what they were probably thinking of.

So what I ended up using was my hands, a hammer and a piece of wood, (actually a wooden stir stick for paint you get at Home Depot) that I had lying around. It worked like a charm. You sit inside the car facing out. Place the tip of the wood under the trim piece and lightly tap it every couple inches or so and then use your hands to take it off.

I am not planning on putting the trim back on, however this process did not damage it at all, I could re use them if I really wanted to.

[Gregski]

Looks like I am getting the best results using the Phosphoric acid I bought at home depot. It's the same ingredient as in Naval Jelly but cheaper. I used a brush to put it on and Armor All Car Wash soap with water to clean it off. Here are some shots after a single application.

Now I need to use steel wool to agitate it and keep the surface wet using a squirt bottle,

The link below suggests I use steel wool to agitate it and keep the surface wet using a squirt bottle, rinse, lather, repeat, lol.

Check out this old hot rodders results:

secrets of surface rust removal revealed

[Gregski]

Well looks like steel wool was the secret weapon in this rust removal process. It worked very well to agitate the rust and allow the acid to eat it up. Also paper towels worked great around the edges to keep the acid in place and maintain wettness. One gallon of phosphoric acid is enough to do an entire roof.

I still need to remove the trim between the roof and the quarter panels and remove the windshield to clean out those edges and the ones around the rear window with a wire wheel. Then do a final once over of the whole thing and prep and clean it for primer.

[Gregski]

Got the windshield out just using my hands. I removed the metal trim carefully with my hands, and then used a screw driver to pop out the clips. I think if the molding was new I wouldn't be able to do it with my hands, but in this case it worked. The trim is in good shape, but I don't plan on using it anyway. Now it's time to clean up the opening.

[Gregski]

Ok, once I have everything squeeky clean I will need to do something to keep Mr. Rust from coming back. I think I know the number one answer, which is spray it with Epoxy Primer of some [good] kind.

The pros of Plan A ie epoxy primer are that it will definitely keep the rust at bay, ie keep the moisture out. The cons are that I need an air compressor and a paint gun to apply it. Well maybe, as some companies now make it in a special spray can that you pull a rip cord on and activate the chemicals then apply it.

Plan B which I got from some old timer painters is to primer the bare metal with regular primer, then right away paint it with some paint, any automotive paint. Let the paint be the sealer ie preventer of moisture and rust. Then when it's time to get the vehicle painted [for real] you scuff up the paint and use it as filler and take it from there. If I go this route I plan on rattle canning it with flat black over the primer.

QUESTIONS

1. Has anyone ever used epoxy primer in a spray can, and would you recommend it?

2. What about my plan B?

3. Any other ideas?

be gentle, I'm learning here

[Gregski]

So I'm going to use Omni epoxy primer, any objections?

[Gregski]

got the remaining trim off of the quarter panels, that held the bottom of the vinyl roof on, these pieces were held on by 3 bolts on each side, two in the cabin, and the third in the trunk, so I had to use a 3/8 wrench to get the nuts off, it pays to sit inside your project car day dreaming, as it gave me the opportunity to find these bolts, I thought they were just held on with clips

[Gregski]

got some wire wheels for my 4" angle grinder... FINALLY!!! a regular kind and a cup

and found staples in my rear window sill, I had no idea they used staples to tack the vinyl with, I had no idea staples could go through 19 gauge steel, go figure, wonder if that was a factory install? anybody know?

[Gregski]

All the rust is gone, I must have spent as much time on the silly concave weld spots in the window sills and the rain gutters as I did on the entire roof, but I tell you you can snort cocaine out of 'em, jk.

Having gone through all this trial and error, I don't think I could have done it with one method or a single medium. In my case it took two to Tango, the Phosphoric acid ($15) from Home Depot and the wire wheels ($10) for the angle grinder/drill. So acid to do the heavy lifting and abrasives to get into those tough to get to spots nooks and cranies. Yes steel wool and paper towels get honorable mention as well!

Wait till you see how I primered it.

[Gregski]

1 Quart - OMNI AU MP170 Gray Epoxy Primer - $23.97

1 Pint - OMNI AU MP175 Hardener / Activator you need this to mix it with the primer to "activate it" (or half a dozen other names) - $8.70

1 Quart - Urethane Reducer for thinning out the concauction if need be - $10.86

1 Quart - PPG Acryli-Clean DX330 Wax and Greese Remover (a buddy of mine gave me this a while ago)

1 Can of Lacquer Thinner from Home Depot - for cleaning the spray gun, etc

The auto paint supply shop gave me the stir sticks and the filters for free, super nice people there at Jerry's, except they are closed for lunch, found that out the hard way, lol.

$30 dollar face mask from Home Depot, works really well

$80 dollar spray kit from Harbor Freight, compressor and spray gun combo, did the job, never sprayed with anything better so I don't know what I'm missing

[Gregski]

My high school basketball coach used to ask: "Does practice make perfect?"

"Yes Sir" we would reply.

"No, perfect practice makes perfect!" he would correct us and make us run more lines. (Needless to say the man won the state championship, but we need beer and a camp fire for that story.)

...so I decided to practice on an extra fender I had laying around before shooting the roof. I've never used that type of primer mix nor that type of spray gun (or any for that matter) so if it pooped on anything I rather it wouldn't be my smooth as a baby's butt roof.

At first I could sum up the results in two dreaded words: ORANGE PEEL! So I decided to add 10% of the reducer to the mix, the guy at the paint store said I may need it, and heck I already paid for it so why not have it join the party, right? I also toyed with the gun, increasing and decreasing the amount of paint that comes out of it, I don't know which way I turned the knob, all I know there was no more orange peel.

Here are the pictures of my practice canvas, in it's original, prepped, and primered conditions:

[Gregski]

Well all that was left to do now was to wipe the roof clean, mask it off with some 3 inch wide blue tape and old newspapers and shoot the primer.

Here are some action shots.

[Gregski]

Many words have been written on the subject of automotive painting ranging from rolling on Rustoleam paint to spray painting an entire car with rattle cans to shooting one with a state of the art spray gun. However it seems like every write up starts with Chapter 2 skipping things like gun introductions and comparisons all together. I love learning by comparison, I always say "stare and compare" and you'll figure it out.

So here are some things I learned:

There are two types of spray guns, a syphon type and a gravity fed one. A syphon gun has the paint bottle below it. The paint is sucked out of the bottle using a tube, similar to sucking a milk shake through a straw. I used a syphon type. The other type of gun, is gravity fed, meaning the paint comes from a bottle above the gun, and gravity pulls it down.

I tried to compare the CFMs on both types of guns. Logic would tell one that the syphon style needs more pressure to suck the thick paint up the tube, however I've seen some ratings showing higher pressure requirements on the gravity types rather than the syphon types, so go figure. Maybe someone can set me straight on this. Honestly I don't care, I file this in the "Internals of the VCR" folder. Cause I don't care how it works I just wanna watch a movie, or in this case paint a car.

I was told that orange peal at this stage of the game is not a big deal as it will be covered with build primer which then will be sanded smooth anyway. Although I got lucky and did NOT end up with orange peal, I'm just saying.

You ask 10 different guys on how to go about removing rust off the roof of a car and you'll get 11 opinions! Funny but true.

... and watch the over spray!