I sewed in a new zipper over the winter. There was nothing wrong with my screen, but the fibers of the cotton super base had turned to dust. I ordered a custom zipper from zippersource.com (very good and informative website, bet don't expect your order to arrive quickly... At least they tell you that). 

I used a stitch removal tool to take the stitching out of what was left of my zipper and I used a razor blade as well and then using a thimble and
 heavy-duty thread and an upholstery needle I went to work.  I used pins  to hold the zipper in place on both sides all the way around. I removed the pins as I got near them with the sewing needle.  I kept the zipper open just ahead of the sewing so that I could reach inside and outside of the canvas as I worked from a short stepladder with the top pop in the open position. I made two passes on each side of the zipper for a total of four passes. I'm very pleased with the results and glad it's over. 

Jim

On May 7, 2011, at 9:07 AM, Dave Mcneely <mcneely4@COX.NET> wrote:

> Goodyear Pliobond work for this?  Works on fishing waders wonderfully well.  Stays flexible, even though the waders go into cold water and out into direct sun repeatedly.
> 
> mcneely
> 
> ---- neil n <musomuso@GMAIL.COM> wrote: 
>> And possibly "foolish".
>> 
>> Hours spent was high (learning curves). Still. Shoring it up for
>> another camping season seems worth it, (work being slow and all)
>> Didn't think of adhesive flexibility. I can see how adhesive rigor
>> mortis might not be cool. (repeated tent folding)
>> 
>> D-oh!
>> 
>> Shoulda used the Fabri Tac. Used it on side patches 2-3 years back.
>> AFAIK, it hasn't cracked though it would see slightly less folding I
>> think.
>> 
>> As Haynes manual would say of reusing gaskets, lesser $ Goop may have
>> been "false economy".
>> 
>> 
>> Neil.
>> 
>> On Fri, May 6, 2011 at 8:17 PM, David Beierl <dbeierl@attglobal.net> wrote:
>> 
>> 
>>> 
>>> Brave fellow... ;-)
>>> 
>>> Used Goop to glue the zipper into my coveralls once.  Dunno about sunlight,
>>> but it turned rigid after a few years and broke into segments.  Still held
>>> the zipper in, but it draped a bit oddly with a corner every inch or so.
>>> 
>>> d
>>> 
>>> 
>>> 
>> 
>> 
>> 
>> -- 
>> Neil Nicholson '81 VanaJetta 2.0 "Jaco"
>> 
>> http://tubaneil.googlepages.com/
>> 
>> http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines
> 
> --
> David McNeely