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Anything related to printer controllers not being Duet, RAMPS or Sanguinololu: microprocessors, motor and heater driver circuitry, gEDA/KiCAD issues, soldering tips, etc.
Re: How to calculate stepper motor power requirement? - 8 years ago
Alright, so back EMF is only affecting voltage, not current. Agreed that for this estimate I probably would use the max motor rated current of 2A, rather than my expected current limit of 1.5A, so that gives 5.6W when stationary, what would be a reasonable multiplication factor to account for movement and back EMF? I'm not looking for an exact figure any more, when I first asked the question I eby plankton - Stepper Motors, Servo Motors, DC Motors
Re: How to calculate stepper motor power requirement? - 8 years ago
For my purposes when building a printer, "precise figures" are not really required, I'm only really interested in a max power usage figure (in order to understand the potential power supply requirements), and the max current per phase (in order to choose the correct wire gauge). From your equation we have 3.15W for this motor at rest (much less than I expected), would I be safe to multiply thatby plankton - Stepper Motors, Servo Motors, DC Motors
How to calculate stepper motor power requirement? - 8 years ago
I just want to calculate the max power requirements of my stepper motors so I can factor that into my power supply choice. It sounds like a simple question (P = V x I), but I've found so many conflicting answers on the web that I'm not sure who to believe any more. Some people use the rated voltage (rather than the actual voltage), some multiply the current by the number of phases (and some don'tby plankton - Stepper Motors, Servo Motors, DC Motors
Re: Heat Compensated Bed Support First Test - 8 years ago
Err, I feel like we are in 2 parallel conversations here. you've performed 2 tests that identify the problem you've established a theory that explains the observed test results what am I missing, where is the part where you modified the experiment to prove/disprove the theory?by plankton - Developers
Re: Heat Compensated Bed Support First Test - 8 years ago
That shows the problem, it doesn't establish the cause. If you think the constraint of the bed supports is the cause, then provide a temporary support (at the same 3 reference points) that doesn't constrain lateral movement of the bed, and repeat those 2 tests.by plankton - Developers
Re: Heat Compensated Bed Support First Test - 8 years ago
QuoteI am doing this work to see if my suspicion that the lateral force on the screws is what causes the bed to bow. If that is your only reason then why not gather some empirical data to establish the cause, before embarking on a complete bed support rebuildby plankton - Developers
Re: Heat Compensated Bed Support First Test - 8 years ago
Interesting, the printer I am designing will use a similar size and configuration of bed to yours, so I will have to solve the same problem (I have a slight advantage though in that my bed moves in the Z axis, so shouldn't suffer lateral shaking). Where did you get the figure of 0.7 mm expansion, was that measured or calculated? I was hoping to solve the problem by just using oversized mountingby plankton - Developers
Re: 3D printer build from scratch, tips and hints welcome - 8 years ago
If you've changed the number of teeth on your drive pulley then you'll need to change the steps per millimetre in Marlin for that axis. And to answer your other question, it's normal to start a new thread (unless your question is directly related to the discussion in this thread, which it doesn't seem to be).by plankton - Reprappers
Re: Best 3D Modeling Software - 8 years ago
I took a look at DesignSpark this afternoon, at first glance it looks a good package, and I see what you mean about the way it does fillets (that's quite slick). At first look the drawings are somewhat ugly, and it doesn't seem to have a correct perspective view (which makes it harder to see if a square is really a square), but if I was scouting for a CAD package to learn right now I suspect DSMby plankton - Reprappers
Re: Best 3D Modeling Software - 8 years ago
Quotethe_digital_dentist .... It just isn't good CAD software for 3D printing. I feel totally handicapped by this sub-standard software I'm using...by plankton - Reprappers
Re: Best 3D Modeling Software - 8 years ago
Far be it from me to argue with such well reasoned put downs, let me just say for the OP that if you locked a bunch of 3D printer owners in a room for a year it is doubtful they would be able to reach any consensus on the best CAD software. You will undoubtedly end up investing a lot of time in mastering whichever CAD program you eventually choose (which partly explains why people get so ferventby plankton - Reprappers
Re: Best 3D Modeling Software - 8 years ago
Quotethe_digital_dentist "One to avoid: Sketchup". Disagree with that, Sketchup was by far the easiest to get started with (after trying several of the other free options), and is really intuitive (most the time) and easy to use. I do understand what you mean about the holes, however there is a very simple solution to that, just design everything at 10x scale (the holes only ever happen at verby plankton - Reprappers
Re: 3D printer build from scratch, tips and hints welcome - 8 years ago
QuoteAlso the bearing blocks on the Z might not be the final ones you need, Those bearing blocks are designed for a fully supported rail, and if the printer is anything like the scale that hotend suggests then they should be using supported rails anyway.by plankton - Reprappers
Re: Using ptc heaters for a 400x300 bed ? - 8 years ago
The PTC heater you linked was 12V DC, the silicone heater is 220V AC, I don't think 12V would ever be practical for a 400x300 mm bed (it would require 37.5 Amps for a 450W heater), but a mains voltage heated bed may be much more complex to implement safely, particularly if the heated bed moves (if you are not confident you understand all the risks then don't use mains AC). As a rough guide, theby plankton - Reprappers
Re: Base for vertical Leadscrew - 8 years ago
I've been looking into that recently for my own printer design, this is what I've deduced. The most common way of mounting leadscrews vertically, for our types of application, seems to be with a fixed bearing mount at the bottom, and a floating mount at the top (ie, the floating mount has a little bit of play in it, the fixed bearing block usually has 2 radial bearings spaced slightly apart to pby plankton - General
Re: z will be light "as feather"..? - 8 years ago
So that is what I meant to you before, when I said you had "accounted for weight, but not for mass". A rock in space has negligible weight (due to lack of gravity), your counterbalanced Z platform has negligible weight (due to the counterweight), but both items still have mass, if you strapped a rocket to the rock it would still take energy to get that rock moving, just as it will still take eneby plankton - General
Re: Hello! - 8 years ago
Quotei think the bending will be less problematic at this new weight also. Less yes, but still far too much if you actually plan to use all of that 400x400mm print bed area - how can you print at 0.2 or 0.3 mm layer height, when your print head height varies that much over the width of the bed? Quotez will be light "as feather" with counterweights like in building elevators excellent, that'sby plankton - General
Re: Why does filament get stuck in extruder like this? - 8 years ago
With PLA, heat creep back up the thermal break can also be caused by printing too slowly, or if that is an all metal hotend then it may just be insufficient cooling (heatsink fan not working). You would need to give us more information about the hotend, and the circumstances that caused the blockage.by plankton - General
Re: Hello! - 8 years ago
There are several areas for concern here, as others have already pointed out 5.5 Kg is a large mass to be throwing around at speed, my Mendel 90 X carriage weighs approximately 800 g, it can print at over 100 mm/s but I restrict it to under 60 mm/s because print quality starts to suffer at higher speeds. Your printer will probably have stiffer construction, nevertheless I seriously doubt it willby plankton - General
How do you make the frame square? - 8 years ago
I've been thinking about how I would make a box shape frame out of extruded aluminium, or more specifically, once made, how I can accurately determine the box is square. I know that The DD's solution was to mill his ends, but I don't have the facilities (or any experience) to do that. I'll probably buy the extrusion from Motedis, they will cut extrusion to length for you (but I don't see anythiby plankton - Extruded Aluminum Frames
Re: My first hotend jamb - 8 years ago
Yes, I do something similar, my hotend doesn't start to heat until the bed has reached target temperature, the problem here was purely caused by an accidentally slow first layer print speed (something I hadn't previously considered as a potential problem).by plankton - Mendel90
Re: My first hotend jamb - 9 years ago
Yep, increased first layer speed to 50% and no more jambs (I've printed both halves of the Pi case this afternoon). Thanks for your help, I had no idea that slow print speeds could cause a problem like this.by plankton - Mendel90
Re: My first hotend jamb - 9 years ago
I'm pretty sure you've nailed it! First layer temperature is quite warm (200C) but I've been trying a new slicer and had noticed the first layer speed was slow. I'd been planning to tweak those speed settings, but it wasn't high on my to-do list because it never occurred to me it was a potential problem. Most of my recent prints have been small (like the test cubes) or in ABS, so this must be thby plankton - Mendel90
My first hotend jamb - 9 years ago
Not bad, I've been using my Mendel90 for 10 months and this is the first hotend jamb, however having no experience with jambs I'm trying to work out the cause. I hadn't used the printer for a couple of weeks, but wanted to print a Raspberry Pi case for an Owl nest box web camera I'm making my Dad for Christmas. I did a quick calibration test with a 20mm cube, that printed without problems, so Iby plankton - Mendel90
Re: Build plate warpage - 9 years ago
I agree with DC42, if your X carriage is suspended on round steel bars then it will have a very slight sag in the middle, most people overlook this and assume the print bed is not flat (see my last Blog post for more on that, I've included a spreadsheet that will calculate the theoretical deflection).by plankton - Reprappers
Re: Are direct drive extruders any good? - 9 years ago
@DC42 - I notice your formulae assumes 1/16 microstepping, if you lower the number of microsteps/step from 16 to 8 you double the holding torque (at the expense of some resolution), so in theory that allows a smaller (lighter) motor on your direct drive extruder. For a typical direct drive you might be looking at 75 steps/mm, instead of 150 steps/mm for 1/16 microstepping. Has anyone tried this,by plankton - Reprappers
Re: Anyone using Simplify3D Creator - 9 years ago
I bought it the other week, still getting to know it but no problems so far and very happy with it. I've emailed support twice, and both times had my question answered within a couple of hours (of course outside US office hours it's going to take longer). I don't know whether it needs an internet connection to first activate the program, but it certainly doesn't require a connection to work afteby plankton - General
Deflection formulae for steel rods - 9 years ago
I came across this old post from 2010 that discussed a formulae for calculating the maximum deflection on a steel rod due to any given weight (such as an X axis carriage, hotend and extruder). I won't rehash the maths here (see the original post), but I've created a spreadsheet (attached) to automate the calculations if anyone wants.by plankton - Developers
E3D BigBox - 9 years ago
So what do you guys think of the BigBox? https://www.kickstarter.com/projects/e3dbigbox/the-e3d-bigbox-3d-printer http://bigbox-3d.com/ http://disruptivemagazine.com/blog/disrupting-the-desktop-3d-printing-market-e3d-launches-the-bigbox-3d-printer-to-kickstarter-aiming-to-hit-both-quality-and-price/ Some interesting design choices and specifications: 24 volt direct drive extruder stainlessby plankton - General
Re: Are A4982 drivers supposed to be so noisy? - 9 years ago
I think the resting noise is certainly dependant on some interaction between the 2 motor coils, in that first video you can see me moving the Y carriage in 1mm increments from Pronterface, you can hear the tone alternate between 2 notes with each step (in fact, having just checked that video again I think you can also just make out that I'm turning the pot clockwise as the tone increases)by plankton - Controllers