group assignment here

Electronics Production

Group assignment : Characterize the design rules for your PCB production process

MACHINE WE USE

Roland monoFab SRM-20

relevant technical data fom roland web page roland web page

Cuttable Material Modelling Wax, Chemical Wood, Foam, Acrylic, Poly acetate, ABS, PC board

X, Y, and Z Operation Strokes 203.2 (X) x 152.4 (Y) x 60.5 (Z) mm

Workpiece table size 232.2 (X) x 156.6 (Y) mm

Distance From Collet Tip to Table Max, 130.75mm (5.15 in)

Loadable Workpiece Weight 2 kg (4.4 lb)

X-, Y-, and Z-Axis Drive System Stepping motor

Operating Speed 6 - 1800mm/min 0.24 - 70.87inch/min

Software Resolution 0.01 mm/step (RML-1), 0.001mm/step (NC code) 0.000039 inches/step (RML-1), 0.000039 inches/step (NC code)

Spindle Rotation Speed Adjustable 3000 - 7000 rpm

Milling tools diameter:
1/64" = 0.015625 in = 0.397 mm
1/32" = 0.03125 in = 0.794 mm
1/16" = 0.0625 in = 1.588 mm

First make a test by making a trace of the test model

select the tool following instructions

doing all the process to caracterize the file and generate the g code ( explained above)

doing all the process to caracterize the file and generate the g code ( explained above)

doing all the process to caracterize the file and generate the g code ( explained above)

select user coordinates in the drilling machine

...and doing the file trace

using this parameters:
speed(mm/s): 4
cut depth(mm): 0.1
tool diameter(mm): 0.4
number of offsets(-1 to fill): 4
offset overlap(%): 50
path error(pixels): 1.1
image threshold(0-1): 0.5

the test fails on different occasions. first by the depth of stroke, then because it breaks down in the different passes of correction. We break some tool. finally we discover that it is about the leveling of the support. So following the recommendations of the instructors we decided to build a new support completely and make our own mechanized level

TEST PATTERN OBSERVATIONS

At the beginning of this test, most of the tools were broken in the first attempts to record the test. Thus most of the tests are made with tools whose head has a V-termination. This causes that at a greater depth of engraving the width of the plot increases beyond the nominal width of the tool.
In the different attempts, it is first tested with successive passes, increasing the Z as engraving depth from -0.02 to -0.05 mm (each with the corresponding offset designated in fab modules)   and later a single pass was attempted with Z between -0.05 and -0.07 mm since there was no fear of breaking the tool.

Since this test is made for the subsequent engraving of lines in the different circuits we look especially at the separation between lines and the thickness of these.   In the separation between lines there is no problem in general in the tests since taking into account the deformation produced by the termination in v of the tool tends to a greater separation. However, special care is taken in the width of the lines to be drawn from 0.04 mm. Below thickness it is possible that the line is lost

SOLUTION for the different engraving depths

first as a test we try to establish a base level using an app level of the mobile phone

however, we detect that not only the precision of this method is insufficient, but that the engraving defects are not only due to the correct level of the base but also to the possible imperfections of the sacrificial on its surface, so we opted for the elaboration of a complete surface using the same machine

We disassembled the machine stand and removed the old wooden sacrificial

manufacture with the laser cutting machine of a new sacrificial

fixation of the sacrificial to the platform support of the machine

mechanization of the new sacrificial guaranteeing complete flatness and leveling

mechanization of the newsacrificial guaranteeing complete flatness and leveling

mechanization of the new sacrificial guaranteeing complete flatness and leveling

preparing the elements to be solded according to the tutorial. our fablab instructor provides us with the components and in the tutorial there is an outline of where to weld them. Actually I have no idea or why the board is so, nor the functioning of its components. I just follow the tutorial. attention because at the beginning it is difficult to realize where the components should be located. In the tutorial, far from assigning them a code, they place a scheme of the circuit with another identification. they can only be identified by their symbol and by their qualities. carefully attention also to the polarity of some of its components, this time allready described in the tutorialr

missing process

because some images have been lost or the construction process was not properly documented, following the advice of my local instructor here a similar process carried out in the assignment "output"

output board for complete milling process

this is the png generated to fab modules fabrication process of my input board

fabmodules calculation to generate the cut file

output board done checking lines

this board has been milled with the next configuration in fab modules:
milling :
tool : 0.4 mm
speed : 3 mm/s
cut deph = 0.1 mm
first check lines for cutting : 1 offset
final configuration for cutting : 3 offset
cutting:
speed : 0.5 mm/s
offsets : 3

as another example here is the input board for network

here is the fabmodules process with just 1 offset to see clearly the possible mistakes

and here some problems fixed

and here we have both input and output boards sucessfully milled

here some images about the MODS workflow

It is convenient to start welding from the inside to the outside, because because of the little space there is, you may see serious difficulties in introducing the welder between previously welded components.

The welding process can be a nightmare with such small components. our fablab instructor tells us with great success that a good way is to deposit a little tin on the site of the component ONLY ONE SIDE. it is practically essential to use tweezers Then place the component on top and apply heat with the soldering iron, getting the deposited tin to melt. once fixed one end apply conventional welding to the other end being very careful not to invade other parts of the circuit. finally complete the first solder with something more tin

Once the assembly is finished, we refer to a tutorial for the installation of the software on the board. it talks about downloading a certain executable from a web page and offers an unspecified link for what that software is, much less how it works.

the link leads to a commercial website (via the url) but the page is not loaded in any case..

knowing the name by its url I look for the page and it takes us to a home without any indication of the software that we should download I read that software that does not stop being used is called atmel gnu toolchain. After reading something on the internet I understand that it is a chip configurator included in a software called atmel studio. some specialists consulted tell me that this software is very specialized but of very little use in the professional field, since it is dedicated only to one brand of chips and presents many problems addressing other types. ... something like if a CAD program only drew ikea furniture. So in the absence of alternatives I decide to install this software in the hope of finding something that will help me

Surprisingly in the middle of the installation and without prior notice a visualstudio add-on (presumably a complete SDK) starts to be installed that can alter the current configuration of my installed visual Studio. pisses off huge. after a long search without results I give up using this software and I try to look for Atmel GNU Toolchain by its name with different results

from the own page of atmel we can get to this other (I do not remember how but it is not explicit or immediate) that seems to lead to the desired software

.... but instead it leads to a kind of repository where there are libraries without compiling in open code. is undoubtedly a repository of operators to modify software versions

I try to find a form of installation, or at least a distribution of software that allows me to compile it to make an own installer

but soon I realize that it is impossible, since you have to have installed a lot of programs before with configurations that are as unrecognizable as unknown

I turn back to the atmel page and entering from another link I discover a large amount of software that might contain Atmel GNU Toolchain. I am not going to describe here the long and tedious process of searching through this list, without knowing its use or its usefulness, nor its version, ... I wonder if this is really necessary ...

accessing the original commercial page (through another link provided by a friend) (remember that the tutorial does not work) I get to a kind of forum of common technical questions of the chips they sell, so I wear to look for the famous Atmel GNU Toolchain

this leads to another unadvisable link

fortunately elena cardiel, a fab leon partner sends a link http://www.ladyada.net/learn/avr/setup-win.html, which does not appear in any tutorial that you know of fabacademy, that with a software that does not even it is called the same as the one in the tutorial, it is magical, and installs everything that should be installed, that even now I do not know what it is or how it works

So, with the problem apparently solved, the tutorial continues downloading and installing unknown and unexplained software

a modification of the windows paths

installation of zadig and modification of drivers (the incompatibility and operation of zadig is not explained, a truly useful tool)

Zadig does not find divers. I take a lot to realize that the procedure is not the one that is fuzzily indicated in the tutorial. but the following: I understand that the correct process is: 1. connect the motherboard to the usb port 2. use zadig to copy the driver to my computer 3. connect the two plates 4. use zadig to copy the driver to the new insert

thanks to elena cardiel comments I realize to be prevent from connect both boards at the same computer using instead a mobile charger

check out this unknown file appears

finally a check with different commands and commands from the git console. both what I write and what the console returns is incomprehensible to me

due to problems in the programming of assignment 8 I repeat the programming process of the programmer

After believing that the board worked, I had to check it again and again to see that I could not program the hello board of the subsequent execution. this led to the checks described, to solder and remove the bridge a few times, use with zadig several drivers and find documentation on them in case there was the possibility that for some reason that the drivers were unknown and the reason was, and check the plate a and again (which is not worth documenting because it is a repetitive and exasperating task). finally the reason seemed to be the original programmer, or its connections on my computer. thanks to the help of my tutor who left me another programmer everything was fine, so we broke the bridge and executed the command to prevent a new programming and everything came to work

update deburr sharp and jagged copper traces.

although at the time I did not realize it later during the welding process I proceeded to the smooth sanding of the lines and the removal of the small copper plate from the USB connection

update broken bridge

please go for a complete process to the next assignments

if you find some documentation failures in the board manufacturing process please go for a complete process to the assignment 11 "output new board"

//see complete process input board
//see complete process output board
//see complete process network boards