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Shop Tip #400
© Frank Ford 2008; Photo by FF

It doesn't take a lot of calculation to check the level with a dipstick and write on the can how much is left. This can holds the UV-resistant varnish I use on my back door - it's good for a number of years between applications and the job only takes about 4 ounces.  Now, all I have to do is look at the can on the shelf to see that I have enough for the next time: