Specifications

ProtoMat 95s/II
Manual
57
6.15 Practical tips
•
Set the milling depth such that engraving is too deep
rather than too shallow.
Insufficient depth when engraving increases wear on the milling tool.
•
There are a number of reasons why the milling width (depth) might be uneven
.
It is important that the machine bed is truly clean
.
Adhesive tape residue and such like can have a significant adverse affect on the
milling depth. Millings between the machine bed, drilling base and board reduce
precision.
Greatly distorted materials
bend such that the sag shows underneath; in this case,
secure the edges well with adhesive tape. Another important point for precise milling
depth is that millings and drilling chips are removed by suction
.
•
Hooks can occur between the milling tracks if the incorrect milling
sequence is followed, in particular with circles.
If a circle is to be milled anti-clockwise with a tool which rotates clockwise, fine hooks
can occur between the copper areas if the milling tracks overlap.
The reason for this is that the cutting speed on the outer edges is reduced. The
solution is to select the correct direction of milling.
In addition, you can select the
R
EMOVE SPIKES
option on the
S
TRATEGY
tab in
CircuitCAM when you set up the isolation job.
•
Milling burrs
can be caused by blunt tools or incorrect traverse speeds.
•
Deeper settings can be used to make corrections if the structure being milled permits.
Otherwise, change the tool.
•
Burrs
arising during contour milling or cut edges which are not clean are caused
either by a blunt tool or an incorrect feed rate.
•
With some materials, the colour of the milling pass
gives some indication of the
condition of the tool.
Dark isolation tracks on epoxy materials indicate that the tool is sharp, while lighter
tracks indicate a blunt tool.
•
Drilling burrs
are caused either because the tool is blunt or the head is being lowered
too quickly.
In the first case, change the tool. In the second case, the tool height over the material
must be reduced.
•
Drill deflection
occurs where thin tools which are no longer absolutely sharp are used.
However, surface structure of the material may also be a factor.
Drill deflection cannot be avoided even with a sharp tool if, for example, the glass fibre
structure of FR4 materials penetrates the copper.
Drill deflection is very slight for materials with additional, removable copper film (FR4
material with 18 µm or 9 µm copper coating).