Frankenstein laser engraver



Before going to a rescue RAID, consider the following instructions:

Rules of thumb The older, the printer is better. The current the scanner the better. Scanner-stepper motors are stepper printers often superior. You have in general more steps. Depending on current printer is less than the probability of getting stepping out of it. Stepper motors have all scanners. The older the more likely get a unipolar stepper motors that we use, can not in this project.

Clearly, that the parts of the old equipment is a pain often, but I've had luck with at least the scanner stepper. I had found a service manual for the printer. But this does not really helped.


Scanner / x axis
The scanner is an old Tevion 2400 dpi scanner. Is a Microtek ScanMaker 5800.
The stepper is a 96 step bipolar stepper motor. The description is 2T354207 change.
I don't think that anyone else who says this is a 100 stepper motor. It is not! It has 96 steps. Not more not less.


I have the bed of the scanner as the basis for the entire building.
The rail and the timing belt as well as the sledge, which carried out the photoelectronics.
Even though the carriage had to be shortened to give more space for the laser.
There is something special about the stepper. It has mounted a 4 gear on the Foreplate.
The translation is luckly negligible.
You're still curious about how to calculate I have a look at this page a gear ratio.
It is shown the mathematics in German, but, unless a universal language (or use the Google Translator)
The scanner-stepper is used as the X-axis.


Printer / Y-axis
The printer was an old Epson Stylus Photo 925.
The stepper, the I is rescued oddly described in the service manual.
It says it is a 4-phase 48-pole bipolar stepper motor for 42V (?) but it is a bipolar stepper motors are, not 4 phases but 2.
Turn the shaft by hand and count the steps I came up with 48 steps.
This engine (and plates for pressure head) is used as the Y-axis.
At the end, I realized that the 48 steps or the motor itself is built of the weak point in this. It moves more slowly than the scanner-stepper and clatters on the rod. Here no brass fittings. Vaseline should dampen the negative effects.


Stepper motor specifications:
Tevion 2400 dpi / Microtek 5800


Later I found out that both engines are less it then at least 300 mA.
The bug with the silk print on it mix MAX and MIN of the Poti, still has the easy driver V4.
So in v4, they are printed on the Board, but at the same time the potentiometer by a reverse potentiometer was replaced.
At least that is what I've read over in some forums or the comments at SparkFun.
Intelligent :)


So long story short:
The potentiometer is set to a low resistance, which means that the stepper can deliver a fraction of the current of the easy driver. Max 750mA per coil. The potentiometer is set to 25%. Only, so not in pain scream it.


Stepper motor pin assignment:


On my trip through the endless Deepth of the Internet, I stumbled upon a question often as to the correct pin assignment of the stepper.
You need to take only one piece of wire and connect the pins. If you connect the correct pairs you should feel resistance when turning the stepper


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