Major Problems Setting Up Printrbot Plus

[ianmorgandesign]

Machine: Printrbot Plus
Software: Cura 15.04, Repetier Host

I have the above setup that was passed down to me to get working. I guess it was working at one time, but then the extruder contacted the bed. It sat for a while until I decided to learn about it and get things going again.
I have many questions, so please be willing to read through.

I decided to start from scratch to make sure everything is working well. I uninstalled and reinstalled Cura 15.04 per the Printrbot Guides and Instructions. The Simple.Plus.GettingStartedProfile.ini was installed. Next, I opened the 3mmBox.stl and started to home the axes. In the Printrbot Auto Leveling Guide is states to “Turn both threaded rods (Z axis) counter clockwise until the end tip touches the print bed.

How do you know that you are turning the rods the same amount?

Anyway, I did my best to make sure it was level, dropped it to the bed, and adjusted the Auto Leveling Probe with the spacer and the wooden wrenches. This was the outcome of the print:
IMG_6623.JPG
The extruder moved across the bed and then started dumping filament at this location. After hitting Emergency Stop, I raised the Z axis to the location in the photo.


Ok then, I’ll try Repetier Host. This program was already installed on the computer, so I opened the same 3mmBox.stl, sliced it, and printed. Although the extruder seems too high to print the leading square, it is mushing the actual print. These two operations seem to be opposite of each other.
IMG_6624.JPG


Other questions:
1. Why are my prints going to the very top of the bed? Should they not be in the center? How do I fix this?
2. When I look at the bed settings. It always shows Home as the bottom left point, but when I home all axes, the extruder moves to the top left point. Is this correct?

Am I missing out on some vital information here? Still trying to wrap my head around this stuff. Thanks in advance for any help.

[RetireeJay]

It would help if you copy and paste the EEPROM settings here (M503 or M501 will get them printed into the on-screen "log" of your User Interface).

[ianmorgandesign]

Thanks for the reply, RetireeJay. Very new to this, so trying to figure out all of these terms + G-code as well.

Using Repetier-Host V1.6.2, M501 gets me this:
14:12:52.379 : echo:Stored settings retrieved
14:12:52.379 : echo:Steps per unit:
14:12:52.379 : echo: M92 X80.00 Y80.00 Z2020.00 E96.00
14:12:52.379 : echo:Maximum feedrates (mm/s):
14:12:52.379 : echo: M203 X125.00 Y125.00 Z5.00 E14.00
14:12:52.379 : echo:Maximum Acceleration (mm/s2):
14:12:52.379 : echo: M201 X2000 Y2000 Z30 E10000
14:12:52.379 : echo:Acceleration: S=acceleration, T=retract acceleration
14:12:52.379 : echo: M204 S3000.00 T3000.00
14:12:52.379 : echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
14:12:52.379 : echo: M205 S0.00 T0.00 B20000 X20.00 Z0.40 E5.00
14:12:52.379 : echo:Home offset (mm):
14:12:52.379 : echo: M206 X0.00 Y0.00 Z0.00
14:12:52.379 : echo:PID settings:
14:12:52.379 : echo: M301 P22.20 I1.08 D114.00
14:12:52.379 : echo:Min position (mm):
14:12:52.379 : echo: M210 X0.00 Y0.00 Z0.00
14:12:52.379 : echo:Max position (mm):
14:12:52.379 : echo: M211 X100.00 Y100.00 Z100.00
14:12:52.379 : echo:Bed probe offset (mm):
14:12:52.379 : echo: M212 X20.00 Y0.00 Z0.00

[RetireeJay]

[frankv]

There are two different concepts with the name "Home".

PrintrBot's "Home" is where the X & Y end-stops are triggered, which is (0, 0). When you tell the PrintrBot to "Home", this is where it will go.

Your idea of "Home" is the centre of the build area, which I guess is (100, 100). There ought to be a setting in your slicer to tell it where this "Home" is (but I couldn't find it in Cura 2.1.0).

Looking at your settings, I'd guess that setting M206 to X100 Y100 Z0 would solve it.

[RetireeJay]

Let's try to clarify a bit...

On many recent Printrbots, the Y "Home" switch is actually at Y = Max, not at Y = 0. On other (especially older) Printrbots, Y Home is Y = 0. As far as I know, X always "Homes" to zero. I know that recent Simples use the Y Max for Home; I'm not sure about the new metal Plus.

When I click the little "Home" icons on my old Plus (one with Y = 0 for Home) the nozzle ends up at X = 0, Y = 0.

But where the print starts is another matter entirely. That depends on the slicer. And AFIK, all Printrbots expect the slicer to Center (let's not call it "home") the print at X = 1/2 of X Max and Y = 1/2 of Y Max. I know that Cura has a check mark that you must CLEAR so it does NOT try to center the print at 0, 0. Like this:
CuraMachineSettings.PNG

So it's crucial for you to have the correct bed size set up in Cura or Slic3r in order for it to calculate where the center of the bed is located. And let the slicer find the center of the bed, don't try to do it with M206.

On the other hand, since you have a Z probe, you do need to set the Z offset correctly. I don't have a probe, so I just have to refer you to Printrbot's instructions on that.

[ianmorgandesign]

This morning I set the Z-axis threaded rods fairly close using a business card (forgot to put my feeler gauges in my bag today), recoded M212 to be X200 Y200 Z200 while in Repetier, and then opened Cura and set the bed size there to the same (it was set at 250). The print came out much better (At this point I have no idea why it was printing at the top of the bed before):
IMG_6626.JPG

The height of the 3mm box is almost 4mm, so I'll have to make some adjustments, but at least it's printing. This leads me to more questions, however:
1. Must I have both Cura and Repetier? Was it necessary that I input the bed sizes into both programs?
2. Before I begin the print, I can move manually all 200mm along the X-axis, but Repetier does not change the number or move along the Y-axis when clicked. Shouldn't I be able to?

Thanks for the detailed posts/help. I really appreciate it.

[frankv]

[RetireeJay]

[Mooselake]

The square in your picture looks like it's a bit curled, so don't rely on it's thickness to calibrate your Z axis.

I'd double check that you're using Printrbot's recommended settings, and if not then use them. While we have had users here with access to an NIST traceable calibration lab you likely don't have one, and with the tolerances of commercially produced acme screws and belt pulley's it's very unlikely that you can improve on the factory numbers. Don't fall into the print/measure/calibrate/rinse/repeat trap. Print sizes depend on multiple variables, and mechanics steps/mm is only one of them. Other than the extruder, which you do need to calibrate (short explanation, it depends on how far the gear digs into the filament, what kind of filament, and undoubtedly the phase of the lunar cycle). Print/measure will lead you astray and at best get the values you want for only one size since you're trying to use one variable to control several, and that just doesn't work. In addition to the mechanical movements size is also dependent on the difference between the expected printed trace width and the actual printed value. Accurately calibrating your extruder will fix this, and after you have the steps/mm pretty close you can then print a single wall model, measure that, and re-tweak. See . Ignore anything about reconfiguring and recompiling the firmware, that hasn't been necessary since around 2011 or so, but the rest is still very pertinent.

Doesn't the Metal Plus have a 10 x 10 inch print area, unlike our 8x8 plywood pluses? Again, refer to PB's recommended numbers and use those values, although you may want to take off a bit (say 10mm or so) to allow for the marketing trumps reality claims. The best way is to adjust your home switches until you get the margins adjusted at 0,0, then jog over to the far regions and see how far you can get without hitting the stops, or the hot end either getting off the print area or bumping something. You might even want to tweak until you get all the unprintable margins the same, but that may be a bit excessive and somewhat moosely.

Kirk

[ianmorgandesign]

[ianmorgandesign]

Here's the first "blob" (about 190mm in height) run at a Feedrate of 100.

Definitely having trouble creating the large radius at the bottom of the vessel. From the blobby-ness of it, perhaps the Z axis is slightly too close to the bed?
IMG_6672.JPG
IMG_6673.JPG

[frankv]

Those blobs are due to overhang. The flat piece in the middle looks like it's adhering to the bed just fine, and I'd be very happy with the rest of that piece.

Generally speaking, you can't print overhangs of more than a mm or so at less than about 45 degrees to the bed. At 45 degrees, the new layer only overlaps half of the previous layer, so it doesn't adhere well. 60 degrees is better, with a 2/3 overlap. The alternative is to print with "support"... your slicer will generate infill underneath any overhangs to support them. Once it's solid, you break away the supports, leaving the part you want. That can leave some visible artefacts on the supported piece.

The step in the cup near the top might just about be small enough to get away with upside down. So, if the flat part of your cup was a little smaller, you might be able to print it the other way up... any blobbing would be inside the cup rather than outside.

Or you could redesign the cup to have a slightly larger base, and slope outward more steeply to full diameter. Or even make the base the same size as the outside, so the walls are vertical.

[ianmorgandesign]