12 hours is a bit too long in my experience. I find the oils are completely absorbed within about 3-5 hours, any longer and the excess tends to dry and result in difficult removal as you stated.
A couple of comments on the drying issue
Excerpted from a Mike Phillips Meg's #7 article:
....#7 is a non-drying oil.
One of the many things it can be used for is to make paint look wet, thus the name Show Car Glaze.
The reason it can do this is because it is a non-drying oil.
It's hard to get the "Wet Look" with something they dries"...
A couple of comments on the hard to remove issue (again from the above referenced Mike Phillips article)
"So the mistake most people make when using the #7 is this.
1. They apply it to thick - this makes it extremely hard to remove
2. They try to remove it like a wax.
Two tips.
First Tip - Apply #7 with a thin coat... Use a soft foam applicator pad.
Second Tip - Removing #7 requires a special technique, not the same kind of technique you remove a wax with.
Most people remove their wax like this. Start in one area, begin wiping until all of the wax is removed in that area and then move on to virgin territory.
This will not work for #7. The "Act" of removing #7, tends to "Re-liquefy" the product, basically creating the smearing around effect that you experience when you apply it.
Instead, "Break" or "Disrupt" the "Continuous" layer of film-build and then move on to a virgin area and "Break this film-build up.
You see, #7 doesn't actually dry, but it will "Skin", somewhat like homemade pudding.
This "Skin" is easier to break up and remove then the more liquid film is.
By breaking up the continuous film-build and then moving on, you are exposing a fresh layer of the film to the air where it will skin. The next time you come around, it will be easier to break up and remove.
So the idea is to apply a thin coat to the entire car.
Then, Go around the car two to three times, removing a little bit at a time.
A big soft, high quality, 100% cotton, terry cloth towel works best for the first two passes, and then switch over to a Microfiber polishing cloth for the last pass. Microfiber polishing cloths have an affinity for both water and oil based liquids and will remove oily residues much better with less fiber inflicted scratches.
Anyway, that's what my experience has taught me after applying and removing gallons of #7 over the years, to every kind of car with every known type of paint".
If Mike Phillips doesn't know the intricacies of Meg's #7, then no one does, IMO.
That's why I tend to follow his lead whenever I use Meg's #7
But, as usual, YMMV.
Bob
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