I had thought turpentine, for the reason expressed above. I was very surprised when it didn't work very well. So, since I'm out of acetone right now, I tried rubbing alcohol (70% isopropyl). It worked.
However, it dissolved the sap, distributing it in a thin film wherever the rag went. Using two rags, one in each hand, worked well. Use one soaked in alcohol and with the other (clean and dry), follow and remove the alcohol immediately. Takes a bit of doing, but it isn't too hard.
I tried WD-40 and I had to scrub until my elbows hurt and it still did not remove the pine sap. Even the still liquid sap was hard to remove with WD-40. The best thing I tried was PVC pipe cleaner which can be bought at any hardware store. Check the ingredients on the can. It should have Methyl Ethyl Ketone and Acetone. It also did not hurt the paint job on the car. You might want to test it on an inconspicuous area of paint first and after some rubbing look at the rag and see if there is dissolved paint on it. Wash and re-wax the vehicle after the sap is gone. Hope this is useful.
Oh yes! The acetone worked wonders - just a nail polish remover did a pretty good job, now I will be getting some good acetone. Thanks a million!
Goo Gone Automotive Spray Gel is the best thing for any surface and or clothing that has tree sap.
Rubbing alcohol works for me on the shoe tracks that get on my pergo floor and our car windows.
I used an ice cube and a paper towel.... it freezes the sap and the edge of the cube makes a nice 'scraper'... Use a clean piece of the paper towel to lift off the frozen sap pieces and continue until all sap has been removed.
The best thing to use would be pine sap's natural solvent: turpentine (which is derived from the pine tree.)
reference:
http://www.popularmechanics.com/automotive/sub_care_clinic/1272016.html
Believe it or not I've used Pine Sol to remove sap from my hair and skin. It may work on glass too.
Try acetone. Acetone is a universal solvent. In college chemistry lab we used it to clean glassware that had all kinds of funky stuff in it and it would dissolve everything and leave the glass sparkling clean. It was also used to clean equipment between experiments.
Just thought of something else for removing the sap. WD-40 may work? Never tried it but I have heard it removes tree sap from other surfaces.
Have you tried soaking the glass with Skin So Soft Bath Oil from Avon? It works on just about anything sticky. Soak it really well and scrub with a soft cloth. It may take a while and some "elbow grease" but it should work. Good luck! Yilbit
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