Show all posts by user
http://reprap.org/wiki/CoreXY
Re: With AC mains heated beds... safely... - 2 years ago
In the US, what you call an RCD we call a GFCI (ground fault circuit interrupter), this function is also included in AFCI (arc fault circuit interrupter) devices which additionally trigger if they recognize symptoms of arcing as additional fire protection. GFCIs are required only for certain areas (e.g. wet areas like kitchens, bathrooms, and outdoors). Most US GFCIs I have seen are integrated inby mcdanlj - General
Re: Bonding GT2 belts - 2 years ago
Quoteleadinglights I would worry that shaving the cords may substantially weaken them. Mike Oh, the cords are exposed, but not noticeably shaved. The lapped joint is thicker than the rest of the belt by the thickness of the cords. Feather edging would just increase that excess thickness, and I've seen no evidence that it is necessary. I did this earlier with 6mm GT2 belt, and I tried valiantlyby mcdanlj - General
Re: Bonding GT2 belts - 2 years ago
I needed to make a continuous loop for a laser Z stage that was larger than I could buy as a manufactured continuous loop. I ended up with a flexible CA glue (IC-2000) and a technique that worked very well. It bonds the cords together and runs fine through pulleys. It is perhaps imperfect due to interdigitation being inconsistent from the tooth and gap profiles being different, but in practice iby mcdanlj - General
Re: CoreXY Design Alternative - 3 years ago
If you don't want to do FEA yourself, there's a handy spreadsheet on the openbuilds forumby mcdanlj - Mechanics
Scraping flexible magnetic sheet flat? - 3 years ago
I have a cast aluminum bed sitting in a kinematic mount, with a flexible magnetic sheet on it. The cast bed should be flat (though I didn't think to probe it with a dial indicator before putting the adhesive magnetic sheet on it), but ultimately even after carefully tramming, it's clear from my first layer that it's not perfectly flat. It's not bad (I rarely have adhesion failures printing PETG aby mcdanlj - Mechanics
Re: Assembling V6-clone hot end for first time - 3 years ago
I also have the XCR3D hot end (thanks to your blog post) and I replaced the M3 set screws with M3 countersunk screws long enough to reach past the fins. So much easier to find when I'm doing maintenance, and less likely to strip out the hex socket. I still use anti-seize since it's stainless into aluminum, and I haven't had a problem. I replaced the fan with a 40mm noctua and printed a slim adapby mcdanlj - Reprappers
Re: Issues Z axis - 3 years ago
If you use single-start T8 * 2 rod, it won't back drive, and you get lots of mechanical advantage. Using the 4-start T8 * 8 rod back drives easily and then the worm gear comes into play as an anti-back drive mechanism, but that's simply not necessary if you stick to single-start. I'm in the process of mounting an 850x1500mm bed (laser, not printer) on four T8*2 screws. (There four makes sense beby mcdanlj - CoreXY Machines
Re: Heatsink pastes for hotends - 4 years ago
I'll set down my popcorn long enough to say that I'm sure that your experience in 2012 is definitive and that it demonstrates that the vast majority of us who have experienced long and reliable service with heater cartridges are suffering from a mass hallucination. I'm going to persist in my hallucination, and go back to enjoying my popcorn.by mcdanlj - General
Re: Heatbreak hole's - 4 years ago
I also use that XCR-BP6 hotend. I got one with the setscrews screwed into the heatbreak so tight that I stripped a wrench just trying to remove them (as shipped, without having heated it) so I think quality control isn't perfect. I replace those setscrews with long enough M3 FSC screws to stick out just past the fins. That way, they are easier to get at and have a larger socket, but they still doby mcdanlj - General
Re: What is the name of this cartesian / hbot hybrid kinematics? - 4 years ago
I think it makes sense when the axes are already very asymmetric, as is typical in a laser engraver/cutter. X is typically longer, possibly much longer, than Y, and rastering/engraving is typically done X-major. (Cutting is slow enough that intertia mostly vanishes as a concern relative to motor torque.) In at least the case where I've been lightly considering it (for a laser cutter), the Y axisby mcdanlj - Mechanics
Re: What is the name of this cartesian / hbot hybrid kinematics? - 4 years ago
Thank you! ☺ I just read the docs for M669 and that's wonderfully general.by mcdanlj - Mechanics
What is the name of this cartesian / hbot hybrid kinematics? - 4 years ago
There is an obvious type of kinematics that would almost certainly be terrible for a 3D printer because of its asymmetry, but might be good for a laser cutter, and there's a lot of overlap in technology between the domains. But I don't know what it's called, and it's sufficiently obvious that I expect it to have a real name. Here's a simple schematic diagram. The Y motor has normal cartesianby mcdanlj - Mechanics
Re: Has anyone tried UHMwPE as belt replacement? - 4 years ago
Yes. Search by the "spectra", "dyneema", and "spider wire" trade names and you'll see that it was relatively common, especially for corexy, before inexpensive belts became available with much better quality. Belts are easier. There's a reason you don't see a lot of it these days. ☺by mcdanlj - Mechanics
Re: V slot wheels on precision shafts - 4 years ago
Quotehobbymods Mine is "Vista Metals ATP5" as well. I don't know if that's better or worse than MIC6, but that's all I could find as well. ATP-5 and Alca 5 are basically two trade names for the same alloy. Alca 5 at least is produced in a vertical continuous process that I understand is supposed to improve isotropy. I think ATP-5 might be horizontal continuous process but I'm not sure about thaby mcdanlj - Mechanics
Re: Intermittant diagonal layer shift, how to diagnose? - 4 years ago
Did you ever physically swap the A/B steppers to see whether the problem followed the axis or the stepper?by mcdanlj - CoreXY Machines
Re: Intermittant diagonal layer shift, how to diagnose? - 4 years ago
Quoteruggb This is what I used; This is even simpler; but I didn't find it till after I installed the above. It mounts under the driver if you have one of these, TMC2100 A4988 Drv8825 I can't vouch for this as I did not order any. Those "smoothers" are not flyback diodes, as used to protect against back-emf from a relay or solenoid coil, and are a workaround for a weakness in some stepper drby mcdanlj - CoreXY Machines
Re: Intermittant diagonal layer shift, how to diagnose? - 4 years ago
Like ruggb, I can't come up for a mental model by which noise would account for precisely this symptom. Quotedlc60 I will consider that. In looking back, I think that my problems started when I dressed the cables and mounted the Maestro in this enclosure. ... I wonder if some of you have been correct and the problem might be electrical interference since cables go every which way in an enclosurby mcdanlj - CoreXY Machines
Re: Intermittant diagonal layer shift, how to diagnose? - 4 years ago
Quotedlc60 This isn't a big printer, so the 37oz-in steppers _seemed_ to be adequate... The size of the printer isn't highly relevant to how much torque is needed for XY/AB steppers in your corexy. One more thought: Have you tried swapping stepper motors between stations and see if the problem follows the stepper or the station? If you swapped X and Y (or A and and the problem changed directioby mcdanlj - CoreXY Machines
Re: Intermittant diagonal layer shift, how to diagnose? - 4 years ago
I had this in Y instead of X when I made a mistake putting together my pulley stack-up so that aluminum was rubbing on aluminum, and so it was dripping tiny bits of aluminum dust, some of which got into the linear rails and would sometimes jam. For reasons that were never fully clear to me but probably was related to where the stackup was, it only happened in one direction (towards the back). I eby mcdanlj - CoreXY Machines
Re: Print moves very slow, gcode generated with inkscape - 4 years ago
When you followed the "0.0" hack did you also see in the upstream issue the link to ? Active development in upstream marlin here including But note the concerns about performance of transcendentals in that issue; in klipper all that work happens on a more capable processor and it uses the CPU on the SKR only as a motion controller; a different architecture.by mcdanlj - CoreXY Machines
Re: Print moves very slow, gcode generated with inkscape - 4 years ago
You aren't the first: Since you are are using Marlin, post your ARC_SUPPORT configuration, as well as your CLASSIC_JERK or JUNCTION_DEVIATION configuration. That's the minimum for anyone else to be able to say anything meaningful about your Marlin build and G2/G3 really! And do post a representative sample of your gcode. Make sure you have read: TDD, you are running that off a duet running Rby mcdanlj - CoreXY Machines
Re: Print moves very slow, gcode generated with inkscape - 4 years ago
Might mention which firmware and hardware you are using: The configuration isn't identical across all firmware I understand second-hand but do not know that arc/circle (G2 and G3) processing can be slow on slower processors, and here you benefit both from 32-bit processors and from higher clock speed Might consider posting a representative snippet of the generated gcode, rather than just describy mcdanlj - CoreXY Machines
Re: Problem with SKR 1.4 for pen plotter. Y axis homes but doesn't move after. - 4 years ago
I had exactly this symptom when I had a bad signal cable to an external stepper driver. Initially, the machine worked fine. Then the cable flexed enough that the DIR signal broke, and after that the homing direction was the only direction it would move. It would move until it hit the limit switch, and then it would never move again. Just one more thing to check for...by mcdanlj - CoreXY Machines
Re: Inverted T gantry printer - 4 years ago
First plastic last night. I've decided that even though DD puts his kinematic mount points across the middle of the bed, I prefer full bed length (as I did in my corexy printer). I may replace the bed support with one that runs the full extent of the bed. The spring holding the reference mount down at the front of the bed gets a real workout; I keep tipping the bed while moving the printer. Oveby mcdanlj - Extruded Aluminum Frames
Re: Flat ribbon cable to hotend and extruder - is it a good idea? - 4 years ago
Thanks both! (I've used multiple smaller wires for increased cooling in my electric tractor conversion, where a loose bundle of 12awg wires is cooler than a previous pair of 4awg wires of larger cross-sectional area. There, I am sometimes pulling more than 200A, so it's a different scale, but same concept. ☺)by mcdanlj - General
Re: Flat ribbon cable to hotend and extruder - is it a good idea? - 4 years ago
Quoteetfrench Twisting, not braiding is recommended to reduce noise. Quoteleadinglights I have tested braiding as shown in the photograph and it is effective in reducing noise. it is also a method sometimes used in low level multi conductor signals cables e.g. ecg or multiple photodetectors. My understanding is limited, and I'm not an electrical engineer, so I'd like to understand better here.by mcdanlj - General
Re: Questions about TronXY X5SA - 4 years ago
Quoteobelisk79 I'd only argue that the linear rail 'upgrade' was probably unnecessary. V-wheels really are an excellent linear motion system if assembled properly. You've done a lot to that printer, good stuff, and for what it's worth... Sometimes, I find doing things the hard way rather enjoyable and educational too. The wheels that came with the printer were terrible and shed plastic fibers eby mcdanlj - CoreXY Machines
Re: Questions about TronXY X5SA - 4 years ago
Wow, coming to this thread late and yet only two days after it started! Here's my build log of using several parts from my old Tronxy X5S to make something approaching a Real Printer ("Here's a nickel, kid, go buy yourself a real printer" would be the new Dilbert comic I guess?) I switched to linear rail, aluminum XY motion components, single-motor belt-synchronized single-start Z lead screwsby mcdanlj - CoreXY Machines
Re: Inverted T gantry printer - 4 years ago
Oh, that makes a lot more sense than my original design! "Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away." I think I'll end up sticking the the cantilever, if only because it turns out that it's a better match for my scrap bin; it lets me switch from using some pieces that I could easily use for other projects, to using a piece that I hby mcdanlj - Extruded Aluminum Frames
Re: What's the canonical extruder now? - 4 years ago
Some of the fans have brushless DC motors with integrated ESC and have 3 or 4 leads. Typically: Supply voltage (+5, +12, +24V typical) PWM input (5V typical) Actual speed output (PPR, 5V typical, present on most brushless motor fans) Ground For these, you would want to reduce 12V to 5V for the PWM input. Not generally useful for hotend cooling, other than I guess the ability to report speed sby mcdanlj - General