Specifications

ProtoMat 95s/II

Manual

6.12 Board material

In principle, all board materials can be machined although the LPKF ProtoMat 95s/II is not

intended for machining wood.

However, phenol resins of lesser quality, such as FR 2, can adversely affect the milling

quality.

Glass fibre reinforced epoxy material (FR 4 or G 10) can be a health hazard due to the milling

dust produced (allergies, risk of cancer).

Tool service life is also substantially reduced.

Caution

Never work without the extractor running.

We recommend epoxy material without glass fibre (FR 3). A total thickness of 1.5 mm with a

35 µm copper coating is normally used.

With top milling quality and a high tool service life, no disadvantages with regard to FR 4 are

known other than a slightly reduced mechanical bearing capacity (breakage).

This should not be a significant drawback for prototype boards unless particularly

heavy components are to be mounted.

With 17 µm material even finer milling passes can be engraved at a higher packing density.

For galvanically through-hole-plated, double-sided PCBs FR4 material, 5 - 17 µm Cu

thickness is used to prevent an excessively thick copper layer after galvanic copper

application.

Compromises must be taken for 70 µm material when setting the milling depth in that a

deeper milling depth results in wider milling passes of 0.3 to 0.6 mm.

Special board materials with a thicker copper layer of up to 300 µm can no longer be

machined with the LPKF Universal Cutter.

Contour cutters or special tools are needed for these materials.

In these cases, we would ask that you consult us and send sample material so that we

can carry out any tests which may be necessary.

The following materials have proved particularly successful for RF and microwave

applications:

Rogers: R0

4000

RT/duroid

, TMM

, Ultralam

A drilling base is essential for all machining processes on board material.

This allows holes to be drilled through the board without damaging the machine.

The drilling base can be made simply of bakelized paper and should be 2 mm thick.