The first thing to experiment with is the type of wood. The wood's grain, finish, moisture content, and other factors can have a dramatic impact on results. Typical operating power ranges for a CO2 laser are from 5 to 50 watts.
Soft woods like pine will burn with little power and are
good for making deep "3D" type images. However, the
grain of pine has to be accounted for before processing the
image. The grain does not burn as fast a rate as the
rest of the wood. This means that you have to include the
grain in the image or go back over the image and take out
the grain. Douglas fir, unless "clear", is generally
not suitable for most imaging applications.
Harder woods are generally better for imaging. They have tighter grain and give more contrast. Some hardwoods, like maple, yield more "blonde" tones and may not give as high a contrast as desired. Alder gives good contrast and has a dark image. It makes a good choice for many applications. Oak is hard and grainy. Imaging results are usually not good. However, line art and outlines will burn fairly well. Ash is similar to Oak.
Depening upon the image, you will want to scan either with or against the grain. This will depend upon the type of wood and the particular image.
The best type of marbles, granites and other stones are black
and have a hardness of between __ and __. Lasers are
not the most practical tool for cutting stone, so traditional
methods are recommended for that purpose.
Stone like black marble is often "engraved" in two ways.
The first is at low power (typically at 5 to 15 watts
with a CO2) so that just the polished surface is taken away
where a lighter color is deisred. In this process the
image is reversed, so less power leaves more of the polished
surface.
The second is where the image is burned in "3D" style deep
into the marble. This can take from 10 to 50 watts of
CO2 power.
BE CAREFUL WHAT PLASTIC YOU ARE WORKING WITH — DANGEROUS
VAPORS CAN RESULT
Plastics that contain chlorine or bromine such as PVC can
create dangerous vapors and dioxins. All work on plastics
shold be done with a Class 1 enclosure and a vacuum system.
Make sure that you have an appropriate filter on the
exhaust.
There are many plastics that will cut and mark very well
with a CO2 type laser. Some welding is possible provided that
the contact points are good and the material is prepared properly.
Acrylic, PETG, ABS, polycarbonate, Nylon 6, and others
will work. Most marking and engraving work is done with
low power 5 to 25 watts; cutting may require higher powers
depending upon the speed desired.
Diode lasers are good for welding of many plastics. Contact
Aim about this process. Combination machines with a
CO2 laser for cutting and marking and a diode laser for welding
can be built by Aim upon request.
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