I am rebuilding my door glass runners, regulators and tracks. Basically, going through everything inside the doors and rear quarters that relates to the windows. I looked for some guidance on replacing the runner material in the rear track and found very little so I thought I would post my experience here.
I removed all of the old material by sharpening one of my 1/2" wide wood chisels and using the flat side to scrape the channel and the rest of the track assembly clean. I used a fiber wheel in my drill over the entire channel piece and 320 grit sandpaper to clean the inside of the channels out and remove the remaining surface rust and glue remnants and get a good sound surface. I wiped the entire piece down with mineral spirits. Now it's ready for application of the new material. I read where people were trying to put the material in as one piece but thought that would never work with the material that I ordered. I did not get the mohair material as it states that it is not as wide as the original material, and I assumed that it would not lap over the edges as the original stuff did. I also read that the fuzzy material with super sticky industrial grade adhesive backing was a good choice other than getting it down in the channel successfully, tight in the corners was impossible. This is because of two reasons; the backing is SUPER STICKY, and the track is curved which makes this choice of material impossible to bend around the curve. The outside of the radius is longer than the inside. Maybe the actual mohair fabric can flex enough to fit in one piece but, with it not being as wide as the original, I didn't choose that option.
My solution was to get the fuzzy material with the sticky back. It is 3-7/8" wide, and I cut it into strips. Two strips (one from each side of the supplied material as the backing is wider than the material) 1-1/2" wide with a leftover strip 7/8" wide in the center. The center 7/8" strip is the most important so cut this strip second. I applied this 7/8" strip in the bottom of the track first leaving some hang over the beginning to fold back behind the channel. Do not pull the entire backing off the material, only a couple of inches at a time. Center it well and stick the beginning good, then you can pull pretty hard on it working down and bending it around the curve. I used a plastic trim removal tool to rub it down to the bottom (pressing pretty hard) of the track while I worked it around the curve. Then on to the sides. I put the triangle piece on first making sure I had enough material to fold over the wide part of the surface area as the original material did. This left a small area of bare metal near the track side edge but, it was no big deal because the track's side material covered this spot just fine. I started and completed the sides in the same way I did the bottom. Making sure I kept the cut edge of the strip down tight in the corner of the track and peeling the backing off the material as I went along, rubbing the material with the plastic tool. There was enough material to fold over the top edge like the original material and both tracks came out excellent! Since the glass runs in the center of the channel and not in the corner, I think the cut down in the corner matters not as long as you keep the material down in the corner tight as you are peeling the backing off. You really can't even see it. Check out my finished product. I did have a couple of fold over edges that didn't stick perfectly but, I was able to use a small amount of 3M weather strip adhesive to correct that.
