Neil's Line Test Files
Neil's Line Test files
Kamakura 2021 Line Test Files
Kamakura 2021 Line Test files. The files were create in Illustrator and Photoshop, without the use of Circuit Design Software.
File Preparation in Mods
The CBA's mods environment is used to convert the files and create the toolpaths for milling the PCB. Mods is a very powerful environment, but without guidance it can be challenging to make it do what you want. It's a node-based programming environment, similar to Max/MSP or PD, but without the differentiation between a dev-mode and a run-mode, which makes things a bit cluttered. The JS UI is applaudable, but we experienced some UI challenges on MacBooks, where the 2-finger gesture for scrolling is also used for zooming.
!!! Note Use a mouse with mods, if you can. Using a MacBook Trackpad will be challenging.
We want to do the following:
- Convert the trace and interior PNGs to RML tool paths for the SRM-20.
We will be using a 1/64 inch bit for the traces and a 1/32 inch bit for the interior (or frame). Why is it actually called interior?
Opening Mods
Go to http://mods.cba.mit.edu
You will be greeted with a nearly empty page, some see it as an empty canvas. PNG to RML.
Right click and do:
Programs -> Open Server Program -> machines/Roland/mill/SRM-20/PCB png
Or open: http://mods.cba.mit.edu/?program=programs/machines/Roland/mill/SRM-20/PCB%20png
The mods program for the Roland SRM-20 should look something like this:
Loading PNG Files
In the read png node click select png files to load the PNG file.
!!! Danger Check the DPI Settings and the size in mm. If the DPI is set to Screen Resolution (72dpi) it is most likely wrong.
Adding a Save Node to Export the RML File
We are not using mods to control the Roland SRM-20, we use it to convert the PNG files into RML tool path files. To export files, we need to add a Save Module.
Right click and do:
Modules -> Open Server Modules -> file/save
One you have the node on your work area, place it near the Roland node.
Connect the output of the node Roland SRM-20 milling machine to the input of the save file node. A visual connection confirms the link.
Setting up the Roland SRM-20 milling machine
In the Roland SRM-20 milling machine node
- Setting Origin X, Y, Z to 0mm
- Set Jog Height
Jog Height is set to 2mm as default. Jun-san prefers 1mm, Tsuchiyama-san suggests 12mm. Jog Height means the vertical distance of the tip of the milling bit while it moves without cutting.
A lower jog height will make the milling process fasters, as less distance will be travelled.
!!! Question How much time is saved by setting the jog height to 1mm rather than 12mm. Maybe Jun-san and Tsuchiyama-san can do a race...?
Matching Mill Sizes
In the set PCB defaults node there are two default settings:
- mill traces (1/64)
- mill outline (1/32) (="interior")
Click the corresponding button, depending if you are using the 1/64 or 1/32 bit.
!!! Danger Double check the Mill bit size, and if you are milling traces or the interior.
Setting the PCB defaults will update the node downstream, updating the parameter accordingly.
Mill Raster 2D Node
- offset number and offset stepover specify how much material is removed next to the traces
- offset number = 4, offset stepover = 0.5
To create and save the RML file, click the calculate button in the mill raster 2D node. Within the node, you can also see a preview image of the output file.
Viewing 2D Tool Path in New Window
The View button brings you to a new window with the detailed 2D toolpath.
Viewing 3D Tool Path in New Window
The view button in the view toolpath node allows you to view the toolpath in 3D.
RML Files
Now we have our two RML files, we are ready for the next step.
