Originally Posted by zbaird
I wonder if it will pop off easily this winter if you let it freeze and the tar hardens? Once the tar is hard you may be able to deflate the boat and sort of roll the material. Stiff stuff doesn't bond well to pliable material when the pliable is bent, if that makes sense. Several raft accessories, rub strakes, thwart attachments, etc are a testament of such that were purposely bonded and then gave up over time with the material being folded. If its not bothering you terribly, which it sounds like it isn't, it may be worth a try before you go hog wild with toluene or other nasty shit that your material doesn't love. Never tried it, just a thought.
I agree. You might not get it 100% off, but you might get off the majority of the tar.
Alternately try a stiff plastic scraper or a metal scraper with rounded corners to pop off the blobs--but do this when it's cold.
Next spring you can get the residue with your chemical or non-chemical of your choice and less elbow grease than trying to get all the tar blobs off manually.
Story time: a friend of mine works for a paving company. They often mill roads or recycle asphalt. When the asphalt is in big chunks, they take it back to the plant and leave it in a pile. If they try to grind or crush it in the summertime, it just makes a gooey sticky mess. They wait until winter when the material and the equipment is cold and then it fractures nicely with much less mess. They then run it through the kiln and add a bit more oil and repave, or sell the "millings" that you can compact on your driveway on a hot summer day and it's almost as good as brand new asphalt (particularly for home non-high-traffic use).