POR-15 putty too thin

Last week I cleaned a few spots to try filling rust holes without welding. The plan for today was to fill the holes with POR-15 putty. It comes in a metal tube, and I expected it to have the consistency of old fashioned spot filler. It turned out to be more liquid than plastic, sort of like really thick paint. I had a hard time filling even these small holes, which were at most about 1/16 in. wide. I ended up leaving some on my working cardboard until it hardened a bit, but that was sticky and difficult to smooth. The photos show the result. I doubt that these were effective repairs, because the material is so thin.



My idea is to buy some fiberglass filler and mix up my own putty. I think Redline has it. I also need to buy some solvent to clean my hands.

Another big disappointment: my latex gloves leaked again. I need to check the POR-15 web site to see if latex is the wrong stuff. Maybe I just keep poking holes in them. Another week with black fingertips!

While I was waiting for the filler to thicken I worked on removing the remaining sound dampening material from the other side of the car. First I tried GooGone, the stuff that smells like lemons. That softened the glue, but there was lots of adhesive and scraping it off was hard because it just wanted to stick to everything. Whatever BMW used was sure good, because after thirty years it still has plenty of stick. Later I switched to paint thinner, because I had a lot more of that. It worked about as well. I finished up wiping with a rag soaked in paint thinner, trying not to breath in too much.

As I suspected, removing the think, felt-like pad and all that glue exposed the beginnings of rust. That will all get the POR-15 treatment.



In the bay next to mine was a 'Vett about the same age, being worked on by a young guy. This brought out the old and experienced Chevy engine builders. During lunch I listened to a fascinating discussion about the differences between ZZ this and that. These guys really know their stuff.

It's Not Full Of Holes

Yesterday I made an encouraging discovery. Some spots I thought were rusted through from the inside out were surface rust with at most tiny rust throughs.

I used this opportunity to practice doing a complete POR-15 repair cycle in one day. What I mean by complete is starting with a rusty spot and ending with the damaged area treated with POR-15.

After grinding off the paint, filler, and loose rust the area is washed with Marine-Clean, thoroughly rinsed, and dried. I used a heat gun to speed up the drying. Next the area is treated with Metal Prep, which converts rust to something more stable. Treated areas must be wet for at least ten minutes. I brushed a coat here, then there, cycling through them all many times. I ended up with a frothy mess of air bubbles trapped in the thickening goo. After drying with the heat gun I brushed on a coat of POR-15. Next Sunday I will try out the putty.

Rear electric window removal

I never got around to ordering the sheet metal shrinker but there is no shortage of things to do until I get that worked out. Today I painted the area where the rear window patch will go with POR-15, and removed the right hand rear electric window.







Previously I had removed the interior panels, but to get to the rusted areas I needed to remove the electric window lift mechanism. First I removed the six 1Omm bolts that attach a black bracket to the body, but the bracket would not come out. A chrome trim piece running along the door jam was in the way, and it was attached with pop rivets. Out came the drill. I only had to drill out the top two rivets to free the bracket. At the top of the bracket are two unusual looking bolts that appear to be adjusters. The bolts have slotted ends and lOmm lock nuts. I think they center the glass in the slot. Anyway, I loosened them to get the bracket out but I'm not sure I needed to. One more thing. The rear upper corner is sandwiched in with two other pieces. Check the photo.



After I had the first bracket out, getting the actual motor bracket was a snap. The motor has two wires, one black, one blue, black going to the forward connector. Turns out the window needs to be mostly down to get the thing out; I used a 12 volt jumper battery to crank down the window. Removed two bolts at the bottom and lifted the whole thing out, glass and all.



Behind all this, stuck to the body sheet metal, is some soft stuff probably intended to damp vibrations. I think that needs to come off to treat this area with POR-15, so I'll need to come up with a replacement, something that doesn't absorb moisture.



Another thing. The upper portion of this panel is painted, but the bottom is bare galvanised. I wonder if some rust repair was previously done. Given the amount of moisture this area gets because of the window opening, I wouldn't be supprised.

Finally, here are some shots of the area I painted with POR-15. I used the same little can that came in the kit, which I had sealed with plastic wrap the last time I used it. It was in perfect condition.

New bay, new plan for rear window

First of all I have to say the the weather has been terrible the last couple three weeks. Now I know "terrible" will make mainlander's laugh, but seriously, in Honolulu it rarely rains continuously for one entire day, and for two weeks now it has hardly stopped. Yesterday was pretty good, and finally today was back to normal. Just in time for the Pro Bowl.

Today I moved the car to a different bay at the shop. The guys who work there decided to move the used tire storage from where it had been to where my car was. Something to do with keeping an eye on it. Maybe some folks thought the tires in the pile were useable -- ka-raish! The good news is that the new spot is on the lee side, so when it rains, like it has been, I won't have wet air blowing in on my rust spots. The bad news is that the lee side is the West side, so it gets the afternoon sun. This summer I'll probably lose ten pounds every Sunday from dehydration.



Last Sunday being Super Bowl Without Green Bay I worked on the car. Previously I had cut and bent the patch for under the rear window. Now it was time to curve it.

In cross section the piece looks like a V with a base, like this:

\_/

The sides are almost at right angles, which ASCII art will not depict correctly. On the car the above section will rotate about 120 degrees, so that the left side will be vertical, the base will slant to connect the edge of the window opening and the edge of the trunk, and the right side will angle down slightly, overlapping under the window opening.

The bend is mostly a bow shape with the base on the long edge. My plan was to hammer the base with a smooth hammer to stretch it, and hammer the two edges with a shrinking hammer. The combination should produce the necessary bow.



It didn't work. I got a beautiful bend, but in the wrong direction. In the end my interpretation, which is almost completely without experience, is that even though I was hitting the edges with a shrinking hammer they still stretched, and the base stretched in all directions when all I wanted was to make it longer. At first I used a steel die, then later I tried a wood die thinking it would help with the shrinking. No change. I never did snap a pic of the result. Probably because I was too mad. Bit I should. I finished the day cleaning up the repair area, thinking I would get on a coat of POR-15. But it started to pour, really hard, so POR-15 was out. I just hit it with a lot of metal-prep.

During the week I thought about what to do. My first idea was to abandon the formed patch and attempt a built-up patch. The problem with that is that one of those edges is exposed, and should be a bit radiused. A welded joint would be ugly, especially if I made it. I could set it down and build up the surface with bondo, but on such a big area it will eventually crack and fall apart. I ended up deciding to buy a shrinking tool. As soon as I post this I'm going to check out Harbor Freight. Good thing I kept that failed attempt, maybe I can save it. Or most of it.

2008 Off to a good start

I had a great day at the shop today. First I finished what I started last week, making templates to align the section under the rear window. After that I removed the trunk and cut away the rusty piece with a die grinder.

Last week began with making a cradle for my welder's gas bottle. It's very simple, just 2 x 4s nailed together. I angled the bottle so that the regulator doesn't stick out from the cart.

The templates are made of aluminum. Their purpose is to locate the peak of the window opening after I cut away the rusted section. I might of made them too precise, but I wasn't sure what I would need. Turned out to be very tedious work, file and check, file and check ...


Simple wooden cradle for my argon gas bottle. I tilted the bottle so that the valve and regulator do not stick out.


Fabricating templates from aluminum to position patch.


Two shots of the trunk hinge mechanism before removing. I scribed a cut line with orange grease pencil just above the top of the weather-seal lip.


After first pass with cut-off wheel.


At last the rusted out piece is out. The area inside this boxed-in section looks better than expected.

Next job is to measure for second bend of replacement section. I now plan to put the top under the existing piece to minimize interference with window. As I am making the patch I will treat this area with POR-15.