Inlays with F-engrave

F-engrave 1.73 is being used in this blog post.  The YouTube videos are excellent but the gui has changed enough to need a bit of explanation.

If using linuxcnc: settings -> general settings -> un-check 'suppress comments' can be useful.

Click on any image to enlarge.

The dxf file is a simple set of rectangles.

The main items of interest are the image height and the v-carve selection checked.

In General Settings you may want to enable center format arcs.

The origin is set to center in this example.

Settings used as shown.

Calculate v-carve.

Calculate clean-up.

Save clean-up gcode.

Save v-clean-up gcode.

In this example cuts were deep enough that no clean-up was needed.

Close settings window.

File menu -> save gcode as "name"_female.  This is the v-carve tool path.

Next...

Mirror image.

Re-open v-carve settings.

Check 'add box' and 'prismatic'

Set gap, in this example 1/16"  (-0.0625)

Calculate v-carve.

Calculate clean-up.

Save clean-up g-code

Save v-clean-up gcode.

Close vcarve settings window.

In main window: File menu -> save gcode

Save as "name"_male.  This is the male v-carve path.

There will be up to 6 g-code files.  If using a tool change routine or a tool changer this can be reduced to 2 files using the Linux cat command.  Remove unneeded M2's and add T# and M6's as needed.

For illustration purposes STL files were created using Camotics.

Meshmixer was used to mate the 2 STL files.  The result was brought into QCad to add the dimensions.  If the result isn't exact to the decimal place blame the weird mix of software.  The gap is very close to the intended 0.0625".  This gap provides space for a saw blade between the 2 surfaces.  See why sanding away the pointy tops of the male part before clamping/gluing is a good idea ?

A small note on using F-engrave for inlays: the software calculations are based on a cutter with a true point.  If the cutter has any amount of flat on the end the tool height must be adjusted accordingly.  Even a flat of 0.030" can result in a failed inlay.  Other pit-falls are an off-center cutter point,  a spindle with run-out, and v-bits labelled with a  nominal (not exact) included angle

First Try at a Lithophane

 

The creator of the image above posted it to an internet forum.  I'm assuming it was provided for free use for non-commercial purposes.  This type of image is ideal for creating a lithophane.  Unlike like some of the finely detailed lithophanes posted elsewhere this image won't require micro sized cutting tools or endless hours of cutting.

Recently I've found a source of Corian cut-offs at near give away prices.  Corian is a brand name Solid Surface Material which has translucent properties if not infused with dark pigments.  The piece used in this post is some shade of white.

   To get the lithophane effect the Corian was first milled down to a thickness of 0.130".  As shown in the screenshot above the 1/8" ball end mill will be carving to a max depth of  -0.100 which means only 0.030" of material will remain at the deepest parts of the carving.  The settings shown in the image above are the exact settings used.  A roughing pass was also used but is not shown here.

Camotics was used to check the gcode before cutting.  Camotics can be a bit deceptive depending on how the image view is rotated.  The first image shows the features on the chin a forehead as depressions:

in fact they stand proud of the surface as shown from this angle:

Below is the finished item back lit with a florescent light which makes it appear quite yellow.  When illuminated by natural light, such as hung in a window,  it has a bluish-white hue which I find more attractive but more difficult to photograph.