Its weird, I have always used the little syringes from the hobby store, so the mix should be pretty dang exact. It just seems like it is just a little more pliable than some of the others. I mix mine in the bottom of a beer or soda can ( the concave "dish" on the outside) with a piece of tie wire. It seems to mix real well with very few bubbles. Also, if you need a little extra work time, mix it on the bottom of a full can out of the fridge. Keeping cooler will extend your work time!

As a bonus, you can have a fairly cold beer afterward ;)