Introduction: Wooden Box With a Flexible Top
This box is composed by differents parts which have been cutting with a laser machine (Epilog Laser Mini 40w) and after that they joined between them with a system of hooking which I'm going to explain in the step of design.
The materials are differents types of 4mm depth wood. I divided the box in 8 diferents parts, two laterals, the front, back, the base, the top and two inside walls in order to get three comparments.
The machine is the Epilog Laser mini of 40w
Step 1: Design
I worked with the software AutoCAD. The mesures are in milimeters 180x80x4 (length x width x height).
The most important part of the design is the diferent fixing elements.
They should have the same height that the height of the wooden piece of the base which is 4 mm. This is easy, but the dificult part is the width because it can't be equal as the hold in the base for each fix because like we are cutting with the laser machine, it burns a little part of the material, in my case, it was 0.5mm per hold, so I should add to the width of the fixing element. Everything is called the tolerance.
The other important measure that we should take carefully was the distance between the lines on the top which are going to be cut for achiving the flexibility on the top. The distance between them is nearly 1mm vertically, and the horizontal space is 11.25mm. With this measure we have succeed and it works perfectly
Every fixing elements, which are hooking in the base, were in the middle of the part which they hook because I tried to make the box as more symmetrical as posibble.
The fixing elements for the top are hooking in the laterals, the hold for them are circular and the diameter are a the same of the width of flange in the top thus the machine is going to burn the tolerance so it can rotate with freedom.
Step 2: Parameters for Epilog Laser Mini
Although I did the design with AutoCAD, for printing my pieces with the laser machine I had to use the software Rhinoceros in order to make it easier because printing with AutoCAD gave us several problems.
With Rhinoceros we only need go to Archivo>Imprimir (File>Print) and we get at the window of "Configurar Impresión" .
There, we have to go to "Propiedades" (Properties) where we can configure everything which is needed for a correct printing
We should give to the software the piece size for avoiding that the machine cuts out of the limit.
We must check if we want the machine to make the "Auto Focus" for getting the position of machine's lens or, instead of that, we make it manually.
The machine can do two types of working, vector for cutting and raster for "writing" on the wood.
For the vector we ought to give the speed, power and the frequency. We can´t give a higher speed than it needs because the machine won´t cut the wood that it's the same that a low power. And if we give a low speed or a high power we will burn the wood. The frequency is the number of times that the laser's machine hits with the laser.
So in our case we give to the machine this parameters 40%/90%/500Hz (speed/power/freq.)
The raster setting will be higher in the speed and lower in power. As we can see in the top's photo which is in the intro´s photo, I gave a wrong speed o power because it burnt the piece. I used 58% for speed and 90% of power
After making every individual piece we should'nt have any problems for joining it. And if we did correctly the tolerance's measures, we won't need to glue.