Prototype is printing...

A project log for PCB Exposer

PCB exposer using BluRay laser diode for exposing photosensitized PCBs (etch- and soldermask)

Terje IoTerje Io 06/07/2018 at 06:285 Comments

Laser driver and a motor driver PCB (BoosterPack) for the MSP430 LaunchPad has been completed. Initial print had a lot of backlash:

Picture taken with half the microstepping needed (Y-axis)  for correct resolution, done to reveal individual horizontal lines - they are ~20um high and ~40um apart. Beeing able to discern them means the laser is properly focused.

After tuning the backlash parameter and some mechanical tweaks:

0.2mm is ~4mil. (edit: of course it is ~8mil - sorry about that)

Next, the boring part, write proper documentation...


Terje Io wrote 06/07/2018 at 18:28 point

In order already,  TMC2100 for the exposer.

It is in my plans to add support for TMC2130 SPI drivers to my grbl ARM port as well, I have written a library already - testing remains. I will add  daughter board for my CNC BoosterPack in order to avoid messy cabling - and I need a I2C to SPI bridge as there are no spare pins for direct SPI on the target LaunchPads (Tiva C and MSP432).

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Gravis wrote 06/08/2018 at 10:02 point

Why not just use an existing system like RAMPS?

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Terje Io wrote 06/08/2018 at 12:58 point

What is the fun in that? The last 8bit processor I used was the good old 6502. Anyway - if anybody wants to port the code to support RAMPS they are welcome to do so. The Arduino IDE is (was?) not the rigth toolchain for me - I need a debugger so I ended up with TI processors and their CCS toolchain/IDE.

Ouch - this comment editor is a real pain... Hopefully you do not get a zillion mails because of me messing with it.

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Gravis wrote 06/08/2018 at 14:12 point

The "fun" part is that the software/hardware already exists and thus does not require debugging/building.  You don't have to use the Arduino IDE either.  You can just use the AVR toolchain with most IDEs.  *Facepalm*

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Gravis wrote 06/07/2018 at 17:47 point

If you want to increase the accuracy of your steppers then I recommend using a Trinamic motor controller.

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