Just wanted to update those that may be following this posting - Replacing the screens with no see um screen has become frustrating - at least for me. Today was spent going from store to store that do screen repair to see what they had in spline size. No one had the spline, one place could buy a tad larger spline through their vendor and pull it to make it fit - yikes! Also no one had a roller small enough to insert the 0.100 spline. I did find the spline online
here and they also have the roller
here. I'd have a whole lot of leftover spline if I am to purchase it there. Hehr wants just under $3.00 a ft for .100 spline. No mention from them offering the sale of the roller needed to insert the spline.
My concern is the rigidity of the spline being sold where I can buy it. The spline in the screens now is rigid yet not hard if that makes sense. I felt the spline in the stores and those are squishy. That has me concerned as to the need for the spline to be rigid or can softer spline be used? I'm thinking not as the grove is so small it would just slowly pop/roll out of the groove. My other concern was reusing the spline - I had a heck of a time getting the end to pop up so I could see what the spline looked like. I used an awl to get it out - my tiny watch tools didn't work well for that. I used a letter opener to push it back in - not the best tool for that and will not be used again. I do not want to remove any spline and hope for the best in not breaking it or having it fall apart without replacement on hand if what I take out can't be reused.
Jim - I liked your idea of just putting some of the no see um screen on the outside of the window in addition to the stock screen remaining on. That had me thinking as to how to attach the screen. Magnets came to mind, but the screens are made of aluminum and the only place the magnets have some kind of hold is where the screen brackets (metal) are that hold the screen into the window. It was not a secure hold. Also with the newer windows it would be hard to probably impossible to get the no see um screen to cover the full screen outside the window as it cracks open only an inch or two depending on window.
I will succeed though - just need time to figure out what I am going to do