Skip to content

4. Computer controlled cutting

This week was Mechanical design and these were the assignments


Group assignment:

  • Characterize your lasercutter’s focus, power, speed, rate, kerf, and joint clearance.

Individual assignment:

  • Design, lasercut, and document a parametric press-fit construction kit, accounting for the lasercutter kerf, which can be assembled in multiple ways.

  • Cut something on the vinylcutter.

Extra credit:

  • Include elements that aren’t flat

The Real fun begins now!!!

This week I finally got the chance to work with a Laser and vinyl cutters. I have been eagerly Waiting for this week to come. In this Page I am going to explain everything that I have learnt in this week and also all the projects I had planned to do which are related to this subject.


Before FabAcademy started I had planned out various projects I could do in the lab during the course and the list goes something like this:

  • Laser cut shogi board.
  • Stencils of artworks.
  • wooden watch with living hinges for strap.
  • DIY construction kits of toys and vehicles.
  • frosted glass.

Of the projects mentioned above the first four can be done in my fablab. So, over the course of time I will be completing the projects whenever I find time.



The softwares I have used will be listed below Category wise, you might find a few software which are being mentioned from the previous weeks. The software are categorized as follows

  • Parametric design software
  • Raster Software
  • Vector Software
  • CAM software

Parametric design software

We use parametric design software in order to Design our job works in such a way that we can fine tune our designs to be practically executable in the real world.
Here are the software used this week


FreeCad is an open source software which can do decent Parametric design, the best feature in this software would be the spreadsheet which simplified the process of assigning constraints and adjusting the parameters.

Using FreeCad I have designed a pressfit Comb. I was inspired by fablab Madrid’s work on the comb which was like a multi-tool and had various tests done on a single comb. I wanted to do something similar to it, so for my comb I designed it such that you have two types of scale one which has an increment of .15 mm(with a tooth dedicated to.5mm) or a scale with an increment and decrement of .2mm(with two teeth dedicated to .5mm increment and decrement). The comb also would have a scale for depth and raster and on the other side there will be laser engraved stamp.
Though the idea was cool as soon as I started to design the whole thing felt like a herculean task as soon I realised that I had neither the Skill nor time to do such as task. So I set a much more realistic goal.
So while designing I took cues from a youtube video by OddlyTimbot Willison

I wanted to explore this software last week but I couldn’t, this week after trying FreeCad. Just a quick heads up, I have never used neither of these softwares and while it took around a day or two to figure out FreeCad it took me around a few minutes to get the gist of Fusion360.
In fusion 360 I made my Pressfit construction kit which took around an hour.

Rhino Rhino was explored and more importantly grasshopper was explored, It may take some more time before I can use it with some confidence.

CAM software

I Used RDWorks as my CAM software for Laser cutter

Laser cutter

In my fablab there are two laser cutters one is a 40W and a 150W. This Week all my work was done on the 40W Laser.
before Using The Machine I was instructed on the safety guidelines and the correct way to start the laser cutter.

Machine Specs:

  • Machine Capacity: 40W
  • Type: Table top
  • Laser Type: Glass tube CO2 Laser
  • Connectivity: USB and wifI
  • Controller: Ruida controller
  • Cooling type: Water chiller


  • Always Stay near the Laser when it is running.
  • Always Be aware of the location of nearest fire extinguisher.
  • Wear safety goggles when looking at the job while the laser is running.
  • Always Check wether the Cooling System has enough water.
  • In Case of a big fire Use the fire blanket to extinguish the fire.
  • Let the exhaust run for sometime after the job is done especially after doing work on toxic materials.

TIp: Always double check the parameters especially when doing multiple jobs at once.

Operation: We have ran several tests on varipus parameters and functions like

  • Power
  • Speed
  • Through Power
  • Raster, etc.

We also ran various test by varying parameters like running the operation with and without compressed air.
First we started with the raster tests, here we have to set the following parameters to cut the “____” thick stock of cardboard

  • Power: 80%(min and max)
  • Through Power: 40%
  • Speed: 20%

For text I used different parameters.

  • Power: 30%(min and max)
  • Through Power: 50%
  • Speed: 100%

First I cut the comb with an increments and decrements of 0.2mm for each groove along with two grooves reserved for an increment and decrement of 0.5mm.
After the Comb was done I cut my pressfit squares with a slot width of 5 mm.

I initially planned to cut Cardboard with 5mm thickness but forgot to adjust the slot width before cutting.

Though the pressfit was beautifully cut the slot width was too wide however when I joined two squares and tried to press into the slot of another two joint squares they fit smoothly but they were a little loose but when I changed the orientation of one of the pressfit squares they were tight with no wobble which was peculiar which can be considered as a partial victory.
I adjusted the slot width to match the thcikness of the cardboard and did another pass with the laser cutter this time it was flawless a very snug fit.



I am a BIG FAN of Mobile Suit Gundam Which made me want to make a sticker, so I scanned a photo off of a Manga and photoshopped it so that it can be a suitable for a sticker.