Sergey Batalov, I've identified the problem in the firmware. From the trace you linked to: {DDA:CA end_c:12907, n:2, md:24782000, ssq:2025, esq:230400, dsq:57093, msbssq:10, msbtot:5} In the step acceleration code (dda.c) there is a line that reads: dda->c = (int32_t) dda->c - ((int32_t) (dda->c * 2) / dda->n); The n value reported in the trace is taken from dda->n. When nby madscifi - Firmware - experimental, borrowed, and future
Sergey Batalov, could you post a copy of your config.h file?by madscifi - Firmware - experimental, borrowed, and future
In hope that I can avoid submitting patches that break the firmware in the future I have the following question: What environments and versions are people using to compile Teacup? WinAVR-20100110 Arduino-0018 (windows) with avr-libc 1.6.4 Arduino-0022 (windows) with avr-libc 1.6.4 GCC-AVR (ubuntu/linux) with avr-libc 1.6.8 Is anyone using anything else? Specifically, is anyoneby madscifi - Firmware - experimental, borrowed, and future
How are the driver boards configured in regards to microstepping? The board support 64 microsteps per full step, so 15000 steps per rotation is close to correct if the boards are configured for this (12800 would the the actual step count for a rotation at 64 microsteps assuming a 200 step/rotation motor).by madscifi - Controllers
Different problem. The gen7 provided config.h file defines a macro for power_off, which clashes with the declaration for power_off in pinio.h. It looks like there are a variety of incompatibilities between the gen7 config.h file and the current version of the Teacup firmware. I think someone more familiar with the gen7 hardware will have better luck addressing the problem.by madscifi - Firmware - experimental, borrowed, and future
I'm afraid the C99 mode error is my fault. I submitted a patch that did not compiler under the Arduino compiler (I did not realize that at the time). I've pushed a patch to fix the problem, which no doubt Triffid will integrate soon (or otherwise fix it). In the meantime you can replace the contents of the delay.h file with the following: #ifndef _DELAY_H #define _DELAY_H #include #includeby madscifi - Firmware - experimental, borrowed, and future
It needs the Cygwin environment to compile/run on Windows and I don't have that installed anywhere at the moment. However, until it can actually produce useful output there is little reason to make a precompiled version available as it is not currently usable in its current state. That said, if you do have any use for the output it can produce (a set of SVG files, i think) let me know and I'll geby madscifi - General
I'm very much in favor of the idea of processing the gcode on the pc side and just doing the pulse generation on the controller side. It allows for much easier experimentation, for one. Jitter in the stepper pulses is an interesting issue. It is easy to expend a lot of time eliminating it only to find that it does not really make an observable difference in any actual print. I hacked some code oby madscifi - Firmware - experimental, borrowed, and future
Jeremy, very nice work. It is always good to back check outputs and the goal of improving the quality of Reprap prints is only going to be achieved if someone spends the time to track down the cause of the inaccuracies.by madscifi - Firmware - experimental, borrowed, and future
Sublime - that was exactly what I was looking for. Thanks!by madscifi - General
I remember running across a post sometime in the last couple of months about a new c++ based slicer that someone had started which including a link to the source. I've spent several hours trying to find it again via search/google and I've been completely unsuccessful. Does anyone remember it? Can anyone provide a link? I thought I had bookmarked it but I cannot find my bookmark either. Thank yoby madscifi - General
I'm a computer programmer and started out as an electronics technician back in the 1980s. The open source aspect of the Reprap project is critical, at least as far as my interest in the project is concerned.by madscifi - General
The printing in wood link turned out to be a April fools joke. Open3dp released a real recipe for printing with wood on April 5th.by madscifi - Powder Printing and Selective Laser Sintering
It is true that the uv resins are expensive. They would be a poor choice for making Mendel vertices, for example. On the other hand they might be a good choice for making pulleys for 2mm belts. Or so I imagine at the moment.by madscifi - Powder Printing and Selective Laser Sintering
You are definitely not the only one to find new projects in the middle of a ongoing project. I've got several stacked at the moment, and I'm afraid the pile keeps getting deeper. At least your powderbed project is progressing nicely. I've been trying to avoid the project you linked to, but the quality/precision of the parts is so good that I probably will not be able to resist. My only concern aby madscifi - Powder Printing and Selective Laser Sintering
I believe the bubbles indicate that the extruder temp is too high. Does the extruder make a "popping" sound on occasion while printing?by madscifi - Skeinforge
I would suggest a test point for the REF voltage so that the voltage can be easily read with a voltmeter (at least, I could not identify one in the picture).by madscifi - Controllers
I'm don't know if the design Greg printed is up on Thingiverse or not. However, you can make a reasonable toothed bearing cover using Thing 1362 (with the appropriate settings changed in the scad file). To get something much closer to Greg's design than what I printed above set flanges=0 in the scad file.by madscifi - General Mendel Topics
I tried a 2 mm (*1) belt with a commercial pulley - this completely eliminated the vertical banding on the walls parallel to the y-axis. The print on the left is the best I was able to obtain with a 5 mm belt using bearings for all of the idlers. In reality the banding is pretty subtle and I'm not certain that it would be visible in opaque plastic. The print on the right was done with a 2 mmby madscifi - General Mendel Topics
It is not really possible to say if they will work well without knowing the specs on the motor. You have almost but not quite all of the important bits of information. Almost all of the standard stepper drivers will work with that motor, but as to the question of whether the motor has enough torque you'll have to either find a spec sheet or simply try one.by madscifi - United Kingdom RepRap User Group
No need to apologize. Yes, it moves freely, or at least I think it does. Not quite as freely as the x-axis, but pretty close.by madscifi - General Mendel Topics
I just tried out a new belt. Neoprene, fiberglass reinforcement, more flexible than the previous belt. Same problem. Either my idea of enough tension is completely inadequate, or I should have purchased a less flexible belt, not a more flexible belt. Or both.by madscifi - General Mendel Topics
The 5A rating appears to be for unrealistic. The recommended operating conditions portion of the spec sheet for the IPS6041G (the SO8 part shown in the picture you've linked) lists 1.6A continuous drain current, with a max switching frequency of 3.5kHz. The switching frequency is high enough to be useful for PWM heater control, but some of the current controllers may be using frequencies much higby madscifi - Controllers
The components used on that board look very interesting - diagnostic output with the ability to detect short circuit, open, over temp. I wish they had provided connections to the diagnostic pin on the devices.by madscifi - Controllers
Buback - I have since put an indicator on the bearing and verified that it is not the cause of the problem. But you were right to recommend not dismissing the idea out of hand. I'll give printing at a different speed a try, but I don't think that resonance is the issue. The large vertical motion occurs even when turning very slowly by hand. Resonances may increase the effect, but I believe the bby madscifi - General Mendel Topics
Greg, Nophead - I think you both may be on to something. I put an .0005 (inch) indicator on the backside of the belt just past the bearing and I see a .030 inch (0.76mm) change as I turn the stepper manually. The belt had been held as tightly as I could with one hand and the clamp tightened down with the other. Since the indicator was not exactly parallel to the belt the actual change was evenby madscifi - General Mendel Topics
I've put the bearing back and run a couple of tests. Printed using the same GCODE as before. The leftmost print has the least tension on the belt and the rightmost print has the most tension on the belt. The print using the least tension shows the problem strongly. I think the rightmost shows a bit more banding in person than the middle print, so there does seem to be an window where the bandby madscifi - General Mendel Topics
Based on everyone's comments I've decided that I need to find some sort of crash course on idlers. I found this. Assuming that I understand the terminology (and there is little reason to believe that I do), a bearing with the teeth touching the bearing is an inside flat idler. The recommended minimum diameter for a flat inside idler is that which is equivalent to a 40 groove pulley, or about 63.by madscifi - General Mendel Topics
I've encountered an interesting flaw in test prints made with my recently completed Mendel. The flaw is the rather wide vertical bands on the front and back faces of the test print on the left (the test print on the right is the result after a partial fix outlined below was implemented). These bands appear at the same locations on the front and back sides of the test print (from the perspectiby madscifi - General Mendel Topics
Johnrpm - sorry about that. The images made perfect sense to me, but that is only because I've seen it in reality. The first image is the front view. The blue tape covered tabs are just that, solid tabs. The cardboard defines the powder container and the powder is supposed to be dispensed by the threaded rod. The second image is from the bottom. Is the cross section of the brick tie a cross oby madscifi - Powder Printing and Selective Laser Sintering