Post by larrykoskie on Apr 12, 2015 17:47:57 GMT -5
I don't know what I have done, but my computer won't connect to my Arduino board. I can't even select a port. The Arduino is getting power but I can't upload. I am too frustrated. I am done for a while, I give up. I can't look at it any longer without getting angry. If I continue any longer I will give it up for good. I have to take a break.
Post by larrykoskie on Apr 21, 2015 12:00:41 GMT -5
I am back to giving it another try. After replacing the USB cable I was still having problems uploading. I tried about 6 different downloads of Merlin Firmware and finally found one that would compile. But the LCD screen wouldn't work properly. It lit up and displayed while plugged into the USB cable but when I plugged the power supply the screen washed out. Without the USB cable plugged in the screen was blank, lit up but completely blank. So I ended up replacing the Arduino mega. After compiling the new Arduino the LCD screen lit up and displayed everything like it was supposed to with only the power supply connected. But the Y axis wouldn't move. The X and Z axis worked fine, the extruder and fans too, all but the Y axis. I swapper stepper drivers around and no difference then moved the X to the Y axis then the X axis quit working. I went back to the first Arduino and everything worked correctly except the LCD screen. I uploaded the firmward to the new Arduino a second time and then it worked properly. I think that everything is up and running, now I need to know how to upload a g code and tell it to print. I am ready to print something.
Post by jimustanguitar on Apr 21, 2015 12:40:37 GMT -5
Nice! Sounds like it was a bumpy road with electronics from China, but you finally got it!
So... You want your limit switches (endstops) to be just right and your bed level first. I haven't done this on a cartesian machine, but I'm sure there's a lot of info out there on it. You will also want to configure your slicer to match your machine's dimensions, filament diameter, and nozzle size.
Then you load an STL file into Repetier. There's an "object placement" tab on the right side where you do this. It will then let you move it around and rotate and whatever you want to do for layout.
Then you click on the Slicer tab, select the settings that you want to use, and clikc "Slice with #####". (#### is whatever slicing engine you choose. Everybody has their favorite. I like Cura)
After that, you can click on "start print" and see what happens!
Post by larrykoskie on Apr 21, 2015 20:29:24 GMT -5
I did like you said and it looks like it will work. But when I added the full graphics smart controller the printer is operated off the SD card. To use Repetier I need to unplug the controller. So I guess I can do it that way but how can I transfer a stl file to the SD card so the controller will print the object?
Post by larrykoskie on Apr 22, 2015 16:06:52 GMT -5
Now I have another issue. This one isn't too difficult but I wanted to know if I did something wrong. My bed draws about 20A so it can't be powered by the RAMPS. So I tried to use the RAMPS bed output to light up some 12 volt LEDs and then the + side goes to the Gate on the MOSFET. I ran the +12 volts to the bed then to the center (Drain) on the MOSFET and the -12volt lead to the third leg (Source) of the MOSFET. But the bed heats up all the time. The MOSFET stays on even if I disconnect both of the wires on the RAMPS bed output. I even grounded the Gate on the MOSFET but it stayed on anyway. I think I might need to try another MOSFET. Is there anything that I did wrong in my crude wiring?
Is GND on the RAMPS board the same as GND on your heated bed supply? I didn't quite follow your power supply setup but if you have two isolated power supplies (one powering the RAMPS board and one powering the heated bed) then you need to connect their negative or common rails, otherwise they will float around wherever all willy nilly and 0V on the RAMPS board will actually be +5,000V (or something non-zero) relative to the heated bed supply.
Last Edit: Apr 22, 2015 16:45:57 GMT -5 by msizemore
A few things to check, I'm not familiar with the RAMPS 1. why can't you run the bed directly from the RAMPS, WHat is the resistance measured on the bed. It would have to be 0.6 ohms to draw 20 amps from a 12v supply. Most heated beds are 1.2 ohms = 12/1.2 = 10 amps 2. If the RAMPS board works like most others, the positive output is constant and the ground side is the PWM side, so you would need a PNP type MOSFET as the gate will always be full on connecting it to the RAMPS. SO check to see if the RAMPS is a common Positive or a common Negative on the heated bed putput. 3. If the MOSFET is staying on even with the Gate grounded then the MOSFET is short. 4. You should also use a 660ohm resistor on the Gate to prevent ringing which can damage the MOSFET and a 10K - 100K across the Source and Gate to ensure the gate turns fully OFF (pulled to ground)
To add to what msizemore said (good point), Connect the neg rail of the two power supplies together, NOT the negative of the heated bed outputs together, although they may be the same. Like I said you need to know if the output of the HB is a PWM positive or PWM negative, and if it is PWM at all.??
Last Edit: Apr 22, 2015 16:58:11 GMT -5 by BeeAmaker
Some things are meant to be closed. Your mind isn't one of them.
Post by larrykoskie on Apr 22, 2015 17:32:07 GMT -5
There is only one power supply a 75A 900 watt single output. The bed is www.makerfarm.com/index.php/12-x-12-heat-bed.html that draws more than 20A. The RAMPS input is rated at 11A for the heated bed side. The stepper motor side is rated at 5A input. I will try a new MOSFET and add the resistors.
Post by larrykoskie on Apr 22, 2015 20:20:38 GMT -5
A Mosfet won't work to control the temp of the bed but I had a 30A relay and it works great. But now my Y axis is not moving again and I think that it is the stepper driver. And the extruder stepper won't move either but I had never tried it until today. It might be the stepper driver too.
Post by larrykoskie on Apr 23, 2015 13:34:27 GMT -5
This morning everything was moving like is was supposed to except the extruder stepper. So I swapped and put it on the x axis stepper driver. It moved but was all jumpy. It wouldn't just turn forward or backward just jumped back and forth. So I swapped them back and now the x axis is jumping and shacking back and forth. The extruder stepper still isn't moving and the x axis is all messed up. But the y axis that wasn't moving yesterday is working fine. This is just so confusing.
