Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec May 25, 2017 04:54AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec May 29, 2017 04:57PM |
Registered: 8 years ago Posts: 601 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec May 29, 2017 11:12PM |
Registered: 8 years ago Posts: 776 |
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Origamib
Are you sure it is printing at 200mm/s? Small parts means it will actually spend most of its time accelerating.
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Also, I'm not sure I would rate those pieces as high quality myself.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec June 07, 2017 04:53PM |
Registered: 8 years ago Posts: 88 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec June 07, 2017 07:36PM |
Registered: 8 years ago Posts: 776 |
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sigxcpu
How can be speed related to "travelling across the floor"? Travel = force, force = mass * acceleration, speed is nowhere.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 12, 2017 02:05AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 12, 2017 04:08AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 13, 2017 03:45AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 19, 2017 01:17AM |
Registered: 6 years ago Posts: 20 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 19, 2017 04:51AM |
Registered: 8 years ago Posts: 776 |
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xyze
lkcl, I seriously doubt it was printing at anything near 200 mm/s. You really cannot print small objects that fast.
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One of the main problems when printing small objects is cooling. You cannot print a molten layer of plastic on top of another molten layer of plastic. The layer below has to cool enough so it can fully support the layer above or you will get a really bad surface finish. That is why every slicer has a setting that will slow the print down if the layer takes less than X seconds. That setting is enabled by default.
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In Slic3r
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the setting is under the Cooling tab and is called "Enable Auto Cooling". Slic3r will slow the print speed all the way down to 15 mm/s to try and get a layer to take at least 25 seconds. There are multiple settings that modify the outer perimeter, infill, solid layer and other speeds. Simplify3D has a similar array of settings and I'm sure all other slicers have them too.
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It's rather hard to quantify the actual printing speed (especially for small objects) . You should look at the generated g-code. You can see what your slicer used for the printing speed of the different parts of the print.
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You mention "maximizing mm/s per dollar", but that seams like a rather meaningless metric.
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It's relatively easy to make the mechanics move at 200+ mm/s and spit plastic out at that speed, but if the resultant print looks like a blob of goo, the speed means nothing.
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As pointed out earlier, the "default print speed" in the slicer cannot be used as a measurement of how fast your printing. It's an input, not an output. The g-code is also not 100% reliable because the mechanics of the machine, controller board, firmware and firmware settings can all influence the effective print speed.
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The only way (that I can think of) to get some meaningful metric of how fast a printer can print, would be to come up with a test object, define what an acceptable result would look like and then see how fast you can print the object and still get an acceptable result. The time would be measured in minutes and seconds, not mm/s. Note that the object would have to be large enough that a single layer will take more than 25 seconds at your target speed (or you will have to create some kind of cryogenic cooling system
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Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 19, 2017 09:51AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 20, 2017 03:45AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 20, 2017 03:24PM |
Registered: 6 years ago Posts: 20 |
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lkcl
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xyze
lkcl, I seriously doubt it was printing at anything near 200 mm/s. You really cannot print small objects that fast.
that is correct: in a previous post we checked an acceleration graph and the maximum speed for the 4000mm/sec^2 setting used the speed it could hit within 20mm was more like 150. it's still a staggering achievement for something that costs so little money.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 20, 2017 03:49PM |
Registered: 8 years ago Posts: 776 |
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xyze
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lkcl
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xyze
lkcl, I seriously doubt it was printing at anything near 200 mm/s. You really cannot print small objects that fast.
that is correct: in a previous post we checked an acceleration graph and the maximum speed for the 4000mm/sec^2 setting used the speed it could hit within 20mm was more like 150. it's still a staggering achievement for something that costs so little money.
Have you looked at the gcode file ? Did you confirm that the slicer actually wrote F12000 for the speeds? Your calculations should be based on the values in the gcode file and not the values in your slicer, since those are the values that the firmware will be reading.
G1 E4.56432 F15000.0 G1 X107.9439 Y83.1029 Z0.2 F12000.0 G1 X107.7725 Y83.3408 Z0.2 F12000.0 G1 X107.6551 Y83.6094 Z0.2 F12000.0 G1 X103.1837 Y97.7763 Z0.2 F12000.0 G1 X102.8712 Y98.2436 Z0.2 F12000.0 G1 X102.3565 Y98.4696 Z0.2 F12000.0 G1 X80.8252 Y101.2853 Z0.2 F3000.0 G1 X80.6186 Y101.1712 Z0.2 F3000.0 G1 X80.6662 Y100.94 Z0.2 F3000.0 G1 E4.66432 F15000.0 G1 X81.3644 Y100.3113 Z0.2 F900.0 E4.67381 G1 X81.7274 Y100.0174 Z0.2 F900.0 E4.67853
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 20, 2017 04:09PM |
Registered: 6 years ago Posts: 20 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 20, 2017 06:32PM |
Registered: 8 years ago Posts: 776 |
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xyze
Do you still have the gcode file that was used to print the 200 mm/s part in the video ? Should be easy to look at that file, no ?
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All of the G1 ... F12000 lines listed above are not extruding any filament. Only the last 2 lines are extruding filament (while moving) and those are at 15 mm/s.
G1 X120.9622 Y110.1103 Z0.4 F10800.0 E55.1281 G1 X121.0621 Y110.0696 Z0.4 F10800.0 E55.12919 G1 X121.1479 Y110.0041 Z0.4 F10800.0 E55.13028 G1 X121.2526 Y109.8993 Z0.4 F10800.0 E55.13178 G1 X121.2693 Y109.8513 Z0.4 F10800.0 E55.13229 G1 X121.2418 Y109.8084 Z0.4 F10800.0 E55.13281 G1 E55.03281 F15000.0 G1 X103.6861 Y99.0566 Z0.4 F12000.0 G1 X103.4888 Y98.8317 Z0.4 F12000.0 G1 X103.4536 Y98.5346 Z0.4 F12000.0 G1 X103.5929 Y98.2698 Z0.4 F12000.0 G1 E55.13281 F15000.0 G1 X117.6511 Y84.2116 Z0.4 F10800.0 E55.33367 G1 X117.6662 Y84.1357 Z0.4 F10800.0 E55.33446 G1 X117.6018 Y84.0927 Z0.4 F10800.0 E55.33524 G1 X117.3771 Y84.0927 Z0.4 F10800.0 E55.33751 G1 X117.2735 Y84.1133 Z0.4 F10800.0 E55.33857 G1 X117.1857 Y84.172 Z0.4 F10800.0 E55.33964 G1 X103.2592 Y98.0985 Z0.4 F10800.0 E55.53863 G1 X103.1833 Y98.1136 Z0.4 F10800.0 E55.53941 G1 X103.1403 Y98.0492 Z0.4 F10800.0 E55.54019 G1 X103.1403 Y97.8246 Z0.4 F10800.0 E55.54246
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 21, 2017 03:51PM |
Registered: 6 years ago Posts: 20 |
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lkcl
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xyze
Do you still have the gcode file that was used to print the 200 mm/s part in the video ? Should be easy to look at that file, no ?
no of course not: it was weeks ago, and i really don't keep track of auto-generated file output (edit: attached typescript. it *might* be one of the 70 files in the v3.0 folder. but now that i think about it it might be in the v2.0 folder.)
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lkcl
* cheap and cheerful taobao knock-off which costs $150 and is nominally rated for 40mm / sec but with a bit of tweaking can do 100mm / sec. the budget is still $3000 so you can buy TWENTY cheap and cheerful taobao knock-offs. 100 mm / sec times twenty equals *2000* mm / sec.
maximum build-farm speed using the knock-off: 2000 mm / sec (a whopping SIX TIMES improvement).
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 21, 2017 05:51PM |
Registered: 8 years ago Posts: 776 |
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xyze
Then I guess we will never know what the actual speed was for the object in your video. Posting gcode for a different object does not help. As pointed out in my original post, the speeds in the gcode file can be completely different from what you set in the slicer, depending on the size of the object and other settings.
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lkcl
* cheap and cheerful taobao knock-off which costs $150 and is nominally rated for 40mm / sec but with a bit of tweaking can do 100mm / sec. the budget is still $3000 so you can buy TWENTY cheap and cheerful taobao knock-offs. 100 mm / sec times twenty equals *2000* mm / sec.
maximum build-farm speed using the knock-off: 2000 mm / sec (a whopping SIX TIMES improvement).
I think there are a few things missing in your calculations.
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The base cost of the printer is $190. $150 + $40 for shipping. Then there's the replacement parts like a new Melzi board, Mk3 printbed, etc
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. How much labour goes into upgrading the printer.
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How do you account for that ?
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How often will the cheap printers break down when run 24/7 ?
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Did you measure the time it took to print the part at 50 mm/s and the time it took to print the part at 150 mm/s?
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It's actual printing time that matters, not the slicer setting.
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How can you base all of your calculations on a slicer setting ?
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Father Time does not care what you tell the slicer you would like to print at, it only cares about the actual printing time
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Did you print the part before you made all of your improvements so you could compare before and after to confirm that the money and time you spent was worth it ?
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I'm sorry to say, but the end result of your changes is certainly not "astounding". If I gave you money and you send me that part, I would send it back and ask for a refund. Even the part printed at "50 mm/s" is not of acceptable quality, so unless you can improve the quality to an acceptable level, all the money you "save" on cheap printers will ultimately be wasted. Quality should be your #1 priority, and then go from there. But that's just me. Others may be completely happy with those parts.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 21, 2017 09:55PM |
Registered: 6 years ago Posts: 20 |
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lkcl
the purpose of this exercise is to maximise units printed per hour per dollar, with this _particular_ design being focussed on minimising the cost of components (whereas the other printer i'm designing is focussed on higher quality parts - as opposed to lower priced parts - as a way to increase the target). if we're *right at the beginning* of that exercise, it's not really helpful to make judgements as a way to say that the entire exercise must be invalid, is it?
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lkcl
overall, josef, you're drilling down to a level of detail which really isn't that important at this stage of the exercise, to reach a premature conclusion at best, on something that's still being analysed. can i ask: what is the purpose of doing that?
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 22, 2017 01:00AM |
Registered: 12 years ago Posts: 799 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 22, 2017 02:19AM |
Registered: 8 years ago Posts: 776 |
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xyze
If you can't print an acceptable part in X amount of time, then what is the point of trying to print it in half or a third of the time and then basing your calculations on times that do not produce acceptable parts? If you are really at the beginning of the exercise, then you should not be making claims like "(a whopping SIX TIMES improvement)".
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The only purpose of my original post was to point out that you are not printing at the speed that you think you are and that you are looking at the wrong metric. I thought you might be interested in getting that right.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 22, 2017 04:29AM |
Registered: 8 years ago Posts: 776 |
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Chri
For determining the speed it need some more informations:
* Acceleration (Default and max !), Yerk, max speeds of the firmware (upload configuration .h)
* Accelerations / speeds entered at the slicer software (best to upload the settings file)
* complete Gcode file - upload it
* Time the whole print took.
Chri
// default settings //Anycubic //#define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,392.6,E_STEPS_PER_MM} // Taobao thing #define DEFAULT_AXIS_STEPS_PER_UNIT {100,100,397.6,E_STEPS_PER_MM} #define DEFAULT_MAX_FEEDRATE {400, 400, 6, 30} // (mm/sec) #define DEFAULT_MAX_ACCELERATION {5000,5000,150,8000} // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot. #define DEFAULT_ACCELERATION 5000 // X, Y, Z and E max acceleration in mm/s^2 for printing moves #define DEFAULT_RETRACT_ACCELERATION 5000 // X, Y, Z and E max acceleration in mm/s^2 for r retracts
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 22, 2017 11:53PM |
Registered: 6 years ago Posts: 20 |
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lkcl
so i have a suggestion: i actually really appreciate the focus that you have on detail, which i would otherwise miss (because i have a different kind of mind and focus). it is however a little early: i have a friend assembling one of these (as you can see from the build posts), he's a mechanical engineer just starting on the learning process about 3D printing. could you help him out, when he has questions? i'm attempting to get him to join here, however he's a little reticent after his first experience joining a local community 3D printing forum turned into a bit of a... umm... i want to use colloquial words here that might not be politically correct, whoops
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 23, 2017 03:51PM |
Registered: 8 years ago Posts: 776 |
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xyze
That is exactly why I do not participate in online forums much either. They too often degenerate into pointless arguments (or much worse). This is definitely one of the better behaved forums. I'm glad you are taking my input as constructive criticism, which is exactly how it is meant.
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I can certainly try to help if your friend has questions, but Google already has the answer, and yes, it really is "42".
Cheers and good luck with your project.
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 27, 2017 03:06AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 27, 2017 09:51AM |
Registered: 11 years ago Posts: 5,780 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec August 27, 2017 12:38PM |
Registered: 8 years ago Posts: 776 |
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the_digital_dentist
I love to overbuild things, but that's just ridiculous. Are the ends of the frame members milled square and bolted directly to each other, or is he using all those brackets to hold all the pieces in square alignment?
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Maybe he had a huge, free supply of t-slot hardware.
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I can't think of any other reason someone would create that mess over just buying larger t-slot extrusions. Simply using larger t-slot would have been much cheaper and more rigid, and would have looked a lot nicer. If that's 4040 t-slot, for that small of a frame it is more than rigid enough without any of the corner braces. I hope he's not planning to use end support guide rails and plastic motor/pulley mounts.
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I can't imagine the thought process that led to that, unless it was something like "I want to make, the ugliest, nastiest looking, most difficult to service and operate coreXY printer I can possibly think of." In that case, goal achieved!
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec September 10, 2017 12:19AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec September 12, 2017 12:16AM |
Registered: 8 years ago Posts: 776 |
Re: Cheap-and-cheerful Taobao $150 knock-off running at 200mm/sec November 27, 2017 02:12PM |
Registered: 6 years ago Posts: 28 |