Technical annex and important informations on marking wheels and segments.
Special engraving fonts are available to engrave the marking wheels and the segments. A typeface similar to the DIN 1451 font is used as our standard font. This standard font offers various widths and, according to space requirements or length of text, the following widths are available for selection:
- Narrow letter spacing
- Narrow medium letter spacing
- Medium letter spacing
Other fonts and special characters can be manufactured on request. Please send your inquiry. As regards logos and special characters, a DXF drawing or a vector file is needed. Non-digital files will be charged at cost.
The font height is determined at the marking wheel on the engraving point. The height is measured via the points of engraving. The font height at the marked workpiece is consequently not identical with the font height on the marking wheel. The exact font height at the workpiece considerably depends on the marking depth and the flank angle of the font. If an exact font height requires consideration, a manufacturing allowance must be added at the workpiece and it must also be exactly complied with the marking depth.
Limited space conditions on the workpiece or small diameters may require the use of a tighter font width.
The marking depth chiefly depends on the font height and the workpiece. As a rule, the characters are marked between 0.05 – 0.3mm deep.
Greater depths than 0.4mm are possible, must however be manufactured separately.
The distance between characters and words should not exceed a certain size.
This size depends on the diameter of the marking wheel as well as on the diameter of the workpiece. A rule of thumb is: Distance > 1mm is bridged by a transport point. It has been proven to use a transport point instead of a space. It ensures safe transport of the marking wheel and serves for a better distinction between words and strings.
In this context please also refer to point 10 points of entry/transport.
For exchangeable individual segments we have agreed upon standard font heights.
Segments dia 24mm: 1.5 and 2mm
Segments dia. 35mm and up: 2.5, 3 and 4mm
Other font heights producible on request.
For marking wheels engraved from the solid we start from font heights of 0.4mm and for technical reasons end at 14mm, whereby we do not recommend font heights above 10mm, due to the rapidly increasing pressure.
The position of marking on the workpiece requires prior clarification. For marking wheels engraved from the solid the font orientation cannot be changed afterwards. For some marking wheels for exchangeable segments font orientation can be changed by rotating segments. In this context please refer to the note under marking wheels: Segments rotatable.
For being able to mark during a rotating spindle, six start dots are required to be applied in front of the text. These start dots bridge the time from the first contact of the marking wheel on the rotating workpiece up to achieving the marking depth. Marking directly with the effective text without start dots, the first character would be marked only some one hundred millimetres deep while the last character has achieved the full marking depth. The consequence is an optically irregular and unattractive marking.
Some workpieces may involve no startdotst becoming visible on the workpiece for technical or optical reasons. Therefore, it is possible to rearrange the dots at the marking wheel so they can be removed by further processing or tapping the workpiece.
Plunging the marking wheel into the workpiece should happen as fast as possible, best by means of the maximum feed speed G0.
After the marking wheel having achieved the marking depth it may be necessary to program a short dwell time
(0.05 to 0.2 seconds). Without dwell time the marking wheel would not have sufficient time for unrolling the entire text length. The dwell time would keep the marking wheel at marking depth until the last character is marked into the workpiece. After that, the tool can immediately drive off the workpiece.
Marking thin-walled or unstable workpieces requires special attention. For thin-walled workpieces it is recommended to utilize the entire material strength and to apply drillings after the marking process only. Unstable workpieces may be rapidly pressed away owing to the marking pressure. Therefore, we would like to recommend using marking tools with counter roller for the workpiece being supported by the counter roller during marking.