With the firewall off and everything out of the way, I focused my efforts on repairing the upper corners of the windshield frame. Although the lower corners need repair as well, the upper corners will be easiest so that's where I've decided to start.
After a bit of quick sandblasting to get the worst of the rust and corrosion out of the way, here's what was left of the upper windshield corner. Granted, you can purchase new replacement upper windshield frame corners for about $70 each, but I decided to fabricate my own replacement sections to save a bit of money.
Before doing any removal or repair work, I welded some temporary bracing to the windshield frame to help hold everything in proper alignment while the repairs were completed. The bracing isn't anything elaborate, or pretty for that matter, but it should serve it's purpose.
To start, I removed the corroded portions of the upper corner piece from the top windshield crossbar and windshield side pillar. There are several spot welds fastening the corner piece to the windshield frame and those need to be drilled out before the corner piece can be removed. Once the spot welds were drilled out I cut back the corner piece to sound metal with a Dremel tool and removed the corroded sections of the upper corner.
With the corroded portions of the upper corner removed the entire area was cleaned with a wire wheel.
Before fabricating the replacement section of the upper corner, I first wanted to repair an area of heavy pitting near the top of the windshield side pillar. A small amount of pitting on the windshield frame isn't a problem, but the heavy pitting shown below reduces the structural integrity of the frame and also makes welding difficult since very little metal remains in these areas.
Once again I put my Dremel tool to work and carefully cut out the area of pitting on the windshield side pillar.
Using the piece that was removed as a template, a new section was fabricated from a piece of 16 gauge sheet metal I purchased at Lowe's. Pretty much any mild steel will work here, just be sure to buy sheet metal that's ungalvanized. Using galvanized steel will affect weld integrity and also produce noxious fumes during welding.
After several trips to and from the grinding wheel the replacement piece fit in place quite well. After cleaning the replacement piece and windshield frame with a wire wheel I was ready to weld the patch in place.
With the patch welded in place I finished the repair by grinding the welds flush.
With the windshield frame side pillar repair completed I focused on fabricating a replacement piece for the passenger's side upper corner. To start I made a paperboard template to use as a pattern for cutting the replacement piece of sheet metal. Any paperboard (thin cardboard) will work well for this. It takes time, patience and a bit of good guesswork to get everything right, but this is one of the most important steps in fabricating a replacement piece that fits properly into place.
Once the template was finished the shape was transferred onto a piece of 16 gauge sheet metal...
...and then cut and ground to shape. Next I marked the template's kink (bend) points onto the repair piece and bent it to fit. Bending the new piece was done with the help of a vice, wood blocking and rubber mallet. It took several tweaks to get the fit right, but after several tries I was happy and secured the new section in place with some vice grips beforewelding.
Once the welding was complete the welds and protruding edges were ground flush and the entire area cleaned with a wire wheel. Overall the repair came out quite well. Unfortunately, my digital camera died before I could get a picture! I've ordered a new camera so once it arrives I'll add some photos of the completed repair to this update.
With the passenger side upper corner complete, I started work on the drivers side using the same procedure. Below are several photos of the repair to the driver's side windshield frame upper corner.
To be sure the replacement piece was fitted properly I used a screwdriver as a punch to ensure the inside corner of the new piece was fully seated against the windshield frame.
A photo of the new piece partially welded into place. As with the other corner, my camera died before I could snap some photos of the finished product. Hopefully I should have the final photos up within a week.
With the upper windshield corner repairs complete the next step is to repair the lower corners - a much more difficult task due to the extend of the corrosion present and the shape of the lower corner pieces. I'm hoping to find some used lower corner pieces to avoid spending excessive time fabricating patch panels, but if none can be found I'll have no other choice than to fabricate some. Stay tuned for the next update!