I was going to build a mendel 90 as my next printer, but I'm leaning towards the OB1 design. I just ordered my extrusions from openbeamusa.com, and my Helios hot bed from Panucatt. I think I'm just going to use my RAMPS1.4/Arduino - at least initially. I was going to order lead screws/nuts, but didn't see a spec either on your blog or over at thingiverse. Are you using a lead screw, or simpleby jbernardis - General Mendel Topics
The jumpers should already be there. I have Ramps1.4, and the build instructions had me install all of the jumpers by default. The jumpers are physically beneath their respective Pololu driver. You need to remove the driver to make jumpering changes.by jbernardis - RAMPS Electronics
So you're building with an up to date arduino IDE? This is the only reason I have the old IDE on my system. I've never tried 1.0. I'd love to uninstall 0.23by jbernardis - Firmware - mainstream and related support
I noticed that too. Most of the main logic has been moved to marlin_main.cpp. There was a comment that said it was better for those who are building with the command line interface, but I was able to build and upload successfully with the Arduino IDE (0.23, not 1.0)by jbernardis - Firmware - mainstream and related support
Also make sure your grub screws are tightened. That got me early on.by jbernardis - General Mendel Topics
For one or two connectors I manage to crimp with pliers followed by a bit of solderby jbernardis - Reprappers
yes - the "analog" pins are the same as PWM, although PWM is probably more accurate. PWM is a digital way to simulate analog. and yes - if it is an analog (PWM) pin then you can output a range of values 0-255, with 255 being full on. If you only sent a 1, I doubt you saw any result on whatever device you are trying to turn on. Bear in mind, you can't power things like fans, heaters, or even aby jbernardis - Firmware - mainstream and related support
I assume you managed to compile and upload the firmware?by jbernardis - General Mendel Topics
I think I have a solution that I prefer. Instead of splitting the file, I can insert the following into the file just prior to the layer change. The layer height and last e value I can get as I parse the existing gcode . . initial part of file just up to layer change . ; ****************** Inserted code starts here G1 Zlayerheight+5 Fx ; raise the head 5 millimeters above new layer justby jbernardis - Reprappers
I haven't tried it yet, but I was thinking about doing the same thing. That way, I could control additional fans and lights directly from my host software. With marlin as I read it, everything you say is true. What I have never seen before is the following: If you look at the M42 code within Marlin, it does BOTH a digitalWrite and an analogWrite to the same pin (in that order) with the specifby jbernardis - Firmware - mainstream and related support
I have a similar issue on my machine, but I think I know what it is. After I calibrate my machine, it works fine for a while, but eventually the Z axis height will change. I adjust my endstop to compensate, but this only works for a while, Eventually I hear the sound of missed steps from one of the motors. The axis is no longer level and I need to go through the calibration steps again. Inby jbernardis - General Mendel Topics
I don't know about skeinforge, but you can change this in your firmware. This happened to me too. I changed X ends without thinking about it, but the original had the motor hanging out the back, but the new one had the X motor between the two bars, effectively reversing its direction. BTW - I hate the designs where the motor hangs behind the bars, because I think this unnecessarily torques theby jbernardis - Reprappers
Spark fun has these. Maybe not the cheapest, but they'll doby jbernardis - Reprappers
Splitting the file is a great idea - I hadn't thought of that. So I start the second part with an object already on the print bed. I guess for safety's sake I should add a G1 command to the start of the second part to raise to the correct height - I wouldn't want the head to collide with the object during a coordinated move.by jbernardis - Reprappers
I did notice an axis reset on layer change, and it would be good to take advantage of that, but timing the pause point is hardly controllable. I just hit the pause button and wait for the buffered commands to be consumed. I can't see a way to accurately pause it between layers unless print core is modified to break between buffers at that point.by jbernardis - Reprappers
Yeah - I thought the same thing, but it seemed from everything I read that absolute was somehow preferred. I'll give relative a try. To my understanding, it's just an option within skeinforge (or slic3r) . Nothing else needs to be changed.by jbernardis - Reprappers
What is the correct procedure for changing filaments mid-print? I am using my own host software based on printcore.py, and I am using Marlin firmware. When I got to the point where I wanted to change to a different color, I paused the print, raised the z axis 30 millimeters, and then very carefully so as not to move the X carriage, I removed the old filament and loaded my new color. I had to hby jbernardis - Reprappers
you don't upload the config.h to the arduino. You need to compile the firmware on your PC within the arduino IDE and then upload the resulting object file - actually if you have the IDE set up properly, when you press the upload button, it will compile and then upload with that single action. Of course you need to make your changes to the config.h file before you compileby jbernardis - Reprappers
You are dropping x and or y steps. You might need to boost the signal from your stepper drivers. If you have a ramps board you have pololu drivers and these have a trimpot to adjust output current. Try Turning these up a bit. The setting of the trimpot is a balancing act between dropping steps when too low and motors overheating when too high. It might take some experimentation to find the rby jbernardis - General Mendel Topics
Marlin restricts movement until it knows where things are. When you first power up, you can only move AWAY from each axis home position until you actually home that axis. So if your height is above 10, and you just powered up, the "G1 Z10" command will be ignored until you home the z axis. Perhaps you can achieve what you want with G91 - relative coordinates, G1 Z10 - to move up 10 from wherevby jbernardis - Firmware - mainstream and related support
Can you connect to the arduino with the arduino IDE. I assume you can since that would be how you loaded on the firmware. What port/baud did you use for that?by jbernardis - Reprappers
I think saying the tower looks better is an understatement Glad to have been of helpby jbernardis - General Mendel Topics
Have you tried using retraction? This reverses the filament for a specified amount prior to moves. It cuts down greatly on ooze. You can also speed up your moves. My moves are at 120 mm/s.by jbernardis - Reprappers
These are g code commands. G code normally consists of the movement and extruding commands that your slicer produces, but there are many other commands available (and not all of them start with G) that let you do things like turn arduino pins on and off, set firmware parameters, etc. Most host software provides some mechanism where you can enter g code interactively to directly control you prinby jbernardis - RAMPS Electronics
I agree with polygonhell, but would emphasize one thing. If you re printing a small tower then slowing down can actually be counterproductive because the hot extruder remains too close to the tower. Your only recourse here is, as he says, print multiple copies so that the head moves away for a bit, and/or more agressive cooling. Interestingly, skeinforge has two alternatives in the cool pluginby jbernardis - General Mendel Topics
Well the jury is still out on my use of this plugin. I've had several stl files crash skeinforge inside this plugin, so for the time being, I disabled it. It's a shame too, because even with the segment setting, I had noticeable improvements in my corners.by jbernardis - Skeinforge
Does skeinforge have the ability to insert an alteration file at layer change? I know slic3r supports this, and it seems (to me at least) that this would be an obvious feature, yet I can't seem to find it. Thanksby jbernardis - Skeinforge
I notice on the RAMPS board that a large number of arduino pins are not being used. I even have an LCD on my printer and there still is a large number of pins seemingly available. I know I would be subject to current limitations, but am I right in assuming that I can use these pins for my own purposes? It would be great if this were so because, for marlin at least, I can control these pins viaby jbernardis - RAMPS Electronics
Check your cabling between the printer and the PC. The USB cable cannot be long at all. I had a total of about 5 feet, and everything worked fine. I then installed a USB panel connector on my printer which added about 18 inches to the overall cable length, and I started seeing symptoms you describe. If you cannot shorten the cable length, use an actively powered USB hub/switch in between (butby jbernardis - Reprappers
I used a couple layers of heat shrink tubing. I used a heat gun to shrunk to a tight fit, and it worked just fine.by jbernardis - Reprappers