Clarke CMD300, Инструкция по эксплуатации и техническому обслуживанию

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knob whilst grasping the knurled rim of the scale and turning until the zero on the scale lines
up with the pointer. Back off slightly and start the machine.
Turn the adjuster once again until the zero mark lines up with the pointer and double check
that the cutter is just touching the work - if not, make the necessary adjustment. Any further
movement of the adjuster will commence cutting.
General Notes on Milling
Set up the workpiece in a similar manner to that for drilling.
• Slowly bring the cutter into contact with the work piece and start machining.
• DO NOT attempt to make too bigger cuts than the cutter and machine are capable
of, it is much better and safer to make several small passes.
• Always use an appropriate cutting/cooling fluid whilst machining, which can be
applied with a small brush etc., NOT FINGERS.
• DO NOT allow swarf to build up in the cutting area. Stop the machine and remove
using a suitable implement, (brush etc.).
• When finished turn the machine OFF, return the cutter to its highest position and allow
it to come to a complete stop before attempting to remove the work piece or tool.
• Always finish by cleaning and drying the machine, and storing all tools and accessories
etc., safely.
Cutting Speeds
In order to drill, and particularly mill satisfactorily, it is most important that the correct
cutting speed is used,
Cutting speed is the speed at which the cutting edge of the tool passes over the work.
This is usually expressed in feet per minute or metres per minute.
For a given material there will be an optimum cutting speed for a certain set of machining
conditions, and from this speed the spindle speed (RPM) can be calculated. Factors
affecting the calculation of cutting speed are:
• The material being machined (steel, brass, aluminium etc. - see table below)
• The material the cutter is made from i.e. Carbon steel High speed steel (HSS), carbide,
or ceramics.
Material type meters per min feet per min
Steel (tool) 15 - 18 50 - 60
Mild steel 30 - 38 100 - 125
Cast iron (medium) 18 - 24 60 - 80
Bronzes 24 - 45 80 - 150
Brass (soft) 45 - 60 150 - 200
Aluminum 75 - 105 250 - 350
Please note that It is not within the scope of this manual to provide a tutorial on cutting
speeds or the methods used to determine spindle speeds (RPM), for your particular
application. It is assumed that the operator is familiar with these practices.
A good rule of thumb is, the smaller the hole or depth of cut, and the softer the material to
be machined etc, the faster the speed.