The main purpose for marking it is so you can develop a scale to
gauge your heat with. There is a drawback to this inexpensive woodburner,
and that is every time you adjust the heat settings, it takes a
minute or two for the burner tip to adjust to the new temperature.
It doesn't take long though until you have a good feel for how much
heat you want for different types of work. You can also take some
of your tips that come with your pen, (or extra tips you buy), and
with a dremmel tool you can shape your own custom tips.
This is not the best burner around, and from my experience, after
changing the tips several times, the metal between the post and
the tip begins to oxidize and it gets tough to change the tips.
I always used a pair of channel locks, (pliers will do), and a ceramic
coffee cup with cold water so I wouldn't have to wait 5 minutes
for the tips to cool down.
This type burner is not recommended for permanent use, but if you
are wondering if your desire to woodburn is worth spending $300
on, this can be a cheaper way to find out. If you decide that pyrography
is for you by trying this, then you can confidently buy a better
pen, and you will really enjoy it because the heating and cooling
times of the better pens is measured in seconds, not minutes.
Is this burner effective? Here are a couple gourd's I burned using
one of these Walmart special woodburning pens.