So you have the printer built and the software installed, now for the leap into printing with it.
Turning It On
Before you turn on the printer, double check the wiring one more time. Make sure the colors of the cables all line up (I had an endstop with a plug that was backwards and shorting the board). Here is the RAMPS wiring diagram again.
Ok, time to turn it on. You should see lights turn on flash on the arduino and RAMPS boards. If you don’t (or they instantly turn back off), unplug the power immediately. Your wiring could still be wrong and you might have either a short or a disconnect.
Debugging Wiring Problems
Debugging these problems can be painful if your not an electronics wiz. My best advice is to use a volt meter with a conductivity function (it beeps if the two probes touch). In this mode can you touch the different pins on the board and make sure that they are connected if they are supposed to be and not if they shouldn’t. Starting from basic things like power and then moving on to the peripherals is they way I normally work through the board.
If the problem isn’t obvious from above, you can also try unplugging everything and then one by one start adding the components back until either you find the problem component or until you have everything plugged in and working (remember to turn off the power each time you add something).
Making It Move
The board may power on, but you are still a ways off from being able to print. I recommend testing out your firmware configuration by using pronterface. Open pronterface, select the usb connection, an click connect. Once you have a connection, be prepared to turn off the power. Click the auto-home button, and if the motors start moving the wrong way, kill the power quick. You’ll want to make sure you leave enough room on all 3 axis so that you have time kill the switch before the motors start driving the axis too far one way.
Some common problems you may encounter at this stage are:
- Axis moves the wrong way (invert the direction in the firmware’s Configuration.h)
- Axis doesn’t move, but motor makes noise (turn up the gain on stepper driver)
- Motors don’t stop after hitting the end stop (invert the endstop in the firmware’s Configuration.h)
- Also, it is good to test the endstops by hand. Center the axis, push the endstop switch by hand, and then tell pronterface to move the axis towards the endstop. Make sure it moves when the endstop is open and doesn’t when it is closed.
Another useful trick is to loosen the pinion gears on the stepper motors so that you can test their movement with out actually moving the axis.
Turn on the heated bed and extruder heater in pronterface. The extruder should heat up quickly, but it may take several minutes for the bed to fully warm up. Once the extruder is at temp, move the z-axis up a few cm, and extrude some plastic via pronterface. It may take several cm worth of extrusion length before anything comes out. Make sure the filament is also moving the right way :)
Assuming you have a model in gcode (see slic3r below), load it in pronterface and click print. If you make it through the first layer, consider yourself lucky. Also, try printing something really simple like a cube first. This will make it easier to see what is going wrong. There are many problems that you are likely to encounter at this stage:
- Nothing comes out of the extruder
- Sometimes, it just takes a little extra extruding before anything comes out (even after you just finished getting it to work). This is because extruders tend to ooze a little while they are idle. (Try adding a 1 layer skirt in slic3r.)
- Your temp sensor might be reporting incorrectly. (Make sure your temp sensor is correctly set in the firmware’s Configuration.h)
- The filament is too thick on the plate (Your z-axis 0 is too low. You can move the endstop or adjust the Z offset in slic3r)
- The filament instantly curls up off the plate. (Your Z-axis 0 is likely too high. Same solution as above)
- The filament height and thickness look right, but your part doesn’t stick, or starts to peel after a few layers. (Assuming you are using ABS, Try the ABS juice from Matt’s video. You really can’t add to much to the plate. I haven’t printed with PLA yet)
- The nozzle tears the tape on the printer plate. (Your z=axis 0 is too low. See above)
Got another problem? Let me know and I can add it ;)
Slicing Your Model
You can spend a lot of time tweaking slic3r settings. In fact this topic alone is too long for me to write about. Try starting off with a tutorial like this one. I’m also a firm believer in using the latest version of slic3r. Some people advise that older versions work better, but I have not seen that to be true. In fact, with every new version there are many bug fixes and enhancements. Slic3r is only getting better and better.