An explanation of requirements for customers ordering CNC rotary engraving –
CNC, or computer numerical control, is a method of controlling a machine tool from a file.
In this case, the required file is generated from vectors, or lines, supplied by you (the customer)
But… there is a detail that those used to illustrator (etc) will need explaining –
The vectors used for engraving have zero thickness. They have no “fill” or “stroke”
What this means is that, if you export a filled text object from your graphics application, the shape will be represented by its outline vectors, and my machines cutter will “follow” these lines, leaving your text “empty”.
This isn’t always terrible. The job below is an example of this –
To get “solid” text, like in the photo below, multiple “internal” lines are needed to carve away the inside of the letter. Imagine drawing a 10cm diameter circle on a sheet of paper with a pencil. The outline is one line, but the inside of the shape requires many many lines to fill.
I can, in some instances, generate these lines for you, but, I much prefer you (the customer) to send me the vector file to be cut directly.
Colours can then be added to the cut. Unlike other companies, i dont charge extra for a single colour fill. Multiple colours require masking, and this is time consuming. Possible, but it will increase your bill significantly.
A final point to be aware of is line widths.
Line widths with engraving is a direct result of the physical cutter geometry and the depth of the cut. There’s all sorts of stuff going on which is difficult to sum up with a simple number.
In general, i would strongly suggest just using a single line width, and leaving the rest to me! But, if you really do have something specific that you want doing, i can probably accommodate, and, indeed, can grind custom cutters* to specifics for a job – but, again, its better to just leave it to me.
*note, when i say “custom cutters”, actually all the engraving cutters here are ground from scratch. I buy solid tungsten carbide cylindrical rods, and set the geometry of the cutter from scratch using a Newinghall Model G with diamond wheel, and associated measuring microscopes.
If you export a file from illustrator PLEASE re-open it again before sending it, preferably with another application. Illustrator makes such a mess of exporting DXF files that i would always rather you used a true CAD application, or even Inkscape, but, if you must use Illustrator, please do check your files before sending them across.
So, your checklist –
- I need a DXF file from you, as low a revision as possible (eg R14 or below)
- This should contain the vectors you want cut on a single layer (if you want multiple colour fills or line widths, use additional layers)
- This file should be opened again in another application before it gets here (more people than you might expect send broken files!)