Using Laser.alashed.kz

Laser.alashed.kz consists of a library hidden from the user and a set of generators — each with its own set of parameters, producing a drawing for its own type of object. Generators are divided into groups for easier discovery:

• Boxes

• Boxes with flex

• Trays and Drawer Inserts

• Shelves

• Parts and Samples

• Misc

• Unstable

The parameters of each generator are also grouped.

Units of measurement

All sizes are given in millimeters (mm). There is no option to change the units, and adding one is not planned.

The second way to specify a length is as a multiple of the material thickness, which is one of the default parameters (see below). This lets elements keep their proportions even when some details depend on the material thickness.

The description of a parameter should state its unit — if it is missing anywhere, please file a ticket.

Default parameters

In the web interface this is the bottom group right before the Render button. These are essentially technical settings that relate not so much to the object being created as to the material used and to the way the drawing and the material are processed.

thickness

The thickness of the material being used. This value is referenced in many places to determine sizes of elements — finger joints, hinges and so on. It is very important to set it correctly, especially if fingers are supposed to fit into matching slots. Note that many materials may deviate from their nominal value.

Важно

You should always measure the thickness of each sheet, unless you have a very reliable supplier known for strict adherence to specifications. For (plywood) wooden sheets, even a hundredth of a millimeter noticeably affects the tightness of the fit. Harder and more brittle materials may be even more finicky.

burn

Burn correction, also known as kerf width, is the distance by which the laser must step away from the edge of the part. If the laser ran exactly along the edge, it would cut off the outer contour of the part. Thus the burn value is essentially the laser’s radius, or half the kerf width.

The burn value depends on your laser machine, the material and its thickness. It also depends on whether you want parts with extra material or with undersize tolerance. Porous materials such as wood can be cut oversize (larger burn value) so parts can be pressed in tightly and assembled without glue. Brittle materials (e.g. acrylic) should be cut undersize to leave a gap for glue.

Предупреждение

The burn parameter is slightly counterintuitive. Larger burn values produce a tighter fit. Smaller values produce a looser one.

Small changes to the burn parameter can make a noticeable difference. A typical tuning step is 0.01 or even 0.005 mm, which lets you choose between different forces required to join plywood.

Совет

To find the right burn value, cut a rectangle and measure how much smaller it is than the nominal size. The burn value should be about half of that difference. To check the fit for several values at once, use the BurnTest generator from the «Parts and Samples» group.

spacing

The spacing parameter sets the distance between parts.

It is given as a multiple of material thickness (default: 0.5). An additional absolute offset in millimeters can be added after a colon. For example, 0.5:2 means 0.5 * thickness + 2 mm.

Internally the renderer adds twice the burn value to the calculated spacing to compensate for kerf width.

Примечание

For output formats such as LightBurn (which can add kerf itself and merge touching edges to avoid duplicate cuts), set burn to 0 and set the absolute offset equal to the real kerf, e.g. 0:0.1 (meaning 0 * thickness + 0.1 mm). Don’t forget to enable the «Remove overlapping lines» optimization in LightBurn with a distance no smaller than the kerf.

format

Laser.alashed.kz can produce several formats. Most of them require pstoedit. Without pstoedit, only SVG and postscript (ps) are supported. Otherwise you can also choose:

• dxf

• gcode

• pdf

• plt

Other formats supported by pstoedit can easily be added. Open a ticket on GitHub if you need a specific one.

tabs

Tabs are small bridges between a part and the surrounding material that keep the part from falling out. In theory their width should depend on the burn parameter. But it is more practical to make them independent so they can be adjusted separately. Most parts and generators support this option, but there may be exceptions.

Совет

For plywood, values of 0.2–0.3 mm still allow you to pull the parts out by hand (depending on the laser and the particular material). A bit more and you will need a knife to trim them.

inner_corners

How to handle internal corners. Internal corners are a problem because a round tool, such as a laser or a router, cannot make a sharp internal corner. There are different options:

• loop — creates a loop that fills the corner.

• corner — simply a sharp corner in the toolpath, leaving the radius untouched.

• backarc — a naive implementation with inverted arcs connecting the straight segments.

debug

Most regular users do not need this option.

It adds auxiliary construction lines useful when developing new generators. Only a few elements actually support this parameter. The most noticeable ones are finger holes, which show the boundary of the part they belong to. This helps verify the correctness of slot placement.

reference

Converting vector graphics is error-prone. Many formats have very strange ideas about how their internal units correspond to real-world sizes. If reference is set to a non-zero value, Laser.alashed.kz draws a rectangle of the given length. It can be used to check the drawing’s scale or to figure out how to bring it to the correct proportions.

Common parameters and types

Section parameters

Some generators support an arbitrary number of sections. This can be used for rows or columns of compartments, stepped heights, or any other partitioning of some length into subsections. The standard parameters that use this feature are: sx, sy and sh (instead of x, y and h).

Most generators add walls between compartments, so the total size may end up larger depending on the number of compartments (and the extra walls).

Section sizes are separated by a colon (:), for example 30:25.5:70. Instead of repeating equal values you can use value*numberofsections, e.g. 50*3 — the same as 50:50:50. To divide a length evenly into several sections, use overallwidth/numberofsections — e.g. 120/4 — the same as 30:30:30:30. All these formats can be mixed freely.

mounting_holes

Some generators can create teardrop-shaped mounting holes. To get holes of the correct size you need to specify the shaft and head diameters of the mounting screw. The format is "shaft:head", both diameters in mm (e.g. 3.5:6.5). If only the shaft diameter is given (e.g. 3.5), a round mounting hole is created. Setting the mounting hole diameter parameter to 0 disables their creation.

outside

Most sizes are internal. If a generator offers this parameter, it will recompute internal sizes so that the walls and external elements fit within the given outer dimensions.

Предупреждение

This may be surprising when using edge types with protrusions — hinge eyes, handles, feet etc. — since these are also taken into account. If the outer dimensions are not enough to accommodate these elements, the box may not work correctly. Most generators do not check for such situations (such as a negative height), and the responsibility for the sanity of the result rests with the user.

For generators with multiple compartments, internal walls are also included here. The program sums all sections, subtracts the space for the walls and scales all compartments so they fill the remaining space.

Edge type parameters

All edge types other than the simplest ones have a number of settings that determine their exact appearance. Generators are encouraged to expose these settings to the user. In the web interface they are collapsed. In the console interface they are grouped. The user should keep in mind that not all settings are practical to change. For now Laser.alashed.kz does not allow hiding individual settings.

Finger Joint Settings

finger

width of fingers in multiples of thickness

space

width of gaps between fingers in multiples of thickness

surroundingspaces

the amount of margin before the first and after the last finger. Given in multiples of the regular gap between fingers. The actual margin may be larger if necessary, and may be smaller for very short edges.

style

how finger joints should look. Additional styles may appear in the future. Note that snap fingers are only drawn for fingers of width 1.9 and above.

extra_length

Extend the protruding part of the finger joint so that burn marks can be sanded off. Note that this may be undesirable for joints that are not at 90°, where the corner butts against an opposing cutout.

bottom_lip

Create elements for gluing onto the inside of edges with finger slots. This allows boxes to be stacked one on top of another. Note that edges with finger slots used in other places may not need these elements — they may need to be removed before cutting.

Stackable Edge Settings

For boxes to actually stack, they must have the same width and depth, as well as the same angle, width and height of the feet.

angle

internal angle of the feet.

height

height of the feet

holedistance

distance from the finger slots to the bottom edge. Can be reduced to save height at the expense of the strength of the joint with the bottom of the box.

width

width of the feet

bottom_stabilizers

create elements to be glued onto the inside of the bottom edges for more reliable stacking. Use a value slightly smaller than height (+ holedistance) so that part of the feet remains protruding.

Colors

Generated files use the following color conventions:

Black

Outer edges of a part

Blue

Inner edges of a part

Red

Comments or auxiliary lines not intended for cutting or engraving

Green

Etchings

Примечание

Cutting is usually performed in the order: Green, Blue, Black. If other colors are present, their purpose should be clear from the context.