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My guess is that you have completely wrong setup of tower positions and diagonal rod length. Check it again.
Your printer is likely not levelled as well I would guess.
The fact that moves in Z direction are straight and of a correct length indicates that you have properly selected printer type and steps per mm. XY dimensions depend on the geometry (tower positions and diagonal rod length) and st
by
hercek
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Delta Machines
Right, a loose pulley definitely can be the reason.
by
hercek
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Delta Machines
The only reason I can think of is that the towers are not perpendicular to the bed. This leads to significant X,Y and also Z coordinate error. The Z errors might have been partially mitigated at the bed level by the calibration. But the higher up the printer moves the more tower positions are wrong leading the the part being skewed in all axes (X,Y and Z). You can check that the Z error is there
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hercek
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Delta Machines
Most likely bad configuration. Or bad luck. Maybe something changed in Arduino IDE which needs a code change. The firmware I use was compiled about 3 years ago. I use the printer all the time since without problems. Compiled for Arduino Mega 2560 and RAMPS 1.3 shield. Controlled with Pronterface.
Verification does not complain much here:
Sketch uses 133930 bytes (52%) of program storage space.
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hercek
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Delta Machines
It depends whether you have money or time
The most easy and most costly solution is to update electronics and use RepRap firmware.
The most time consuming way is to use my stalled(*) Repetier branch and callibration.wxm. It is very likely you do not need any HW update but you need some math & firmware loading knowledge and free time to spend. I use it with an AVR board. All the added calib
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hercek
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Delta Machines
Well you can use also these:If you are lazy then try this: If you upgrade to RepRap firmware then a least square calibration of tower positions is built in the firmwareIf you are a math nerd then play with this: If you have towers tilted in a different directions and can measure, guess or derive with calibration.wxm how they are tilted and when you can upgrade to Repetier then you can try my old
by
hercek
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Delta Machines
It looks like your bottom left tower is nearer (or further depending on sign of the error in your charts) to the centre in reality when compared to the geometry data in the firmware.
Plus some slight rise of all edges up - that indicates small error in delta radius or diagonal rod.
If you can handle some math then this may help you:
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hercek
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Delta Machines
I do not have a shaft system but I thought about it in the past.
Anyway, I want to tell that you do not really need any sleeve for the shaft. The sleeve is interesting only from the safety point of view - to avoid rotating shaft wearing out something which may be touching it or so that some loose string does not start to reel up on the shaft.
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hercek
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Delta Machines
Thanks, if you find the retraction acceleration then please let me know.
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hercek
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Delta Machines
I would like to try a flexible shaft approach. I just do not have time now.
The problem I see is how it will behave under high speeds. The shaft torsion results to significant errors. One needs a lot of gearing to mitigate them. The gearing slows down the final retraction speed. Based on the quick on the corner of a napkin calculation it did not look like a clear winner.
What E-axis acceleratio
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hercek
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Delta Machines
Depends on your parts. You shuold check their specification.
Each 3dPrinter stepper typically takes 1-2 A (the exact value is typically settable on the stepper driver).
Hotends typically take about 1 A (check your specific part).
12V heatbeds typically take about 9 A (check your specific part).
So you should look for a power source in the range of 18 and more amperes at 12 volts (i.e. at least
by
hercek
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Delta Machines
I do not have an explanation how fixing a play leading to the carriage rotation can fix the problem with periodically changing wall thickness you presented in the first picture. Carriage rotation play leads to significant errors in the XY-direction. But the problem is that this play should lead to an error which has period of one layer. While the error in your picture has obviously period spread
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hercek
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Delta Machines
More extruded material means thicker walls. Less extruded material means thinner walls. An eccentric pulley on extruder will cause variation in the extruded amount of plastic with the period corresponding to one pulley rotation. If the cube walls are thin enough and filament thick enough then one extruder pulley rotation will correspond to more layers and it may correspond to the pattern you see.
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hercek
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Delta Machines
I do not know DC42 idler pulley assembly.
If the scratch happens only during homing and cause some error only when a carriage is near the home position then it cannot cause the pattern on your print. You must look for a periodic error along the part height. Not a one time error near homing. The homing error may be there but it is a separate issue.
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hercek
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Delta Machines
Probably not. 2 °C looks too low for it.
Is the length of the period of the pattern the same as the timing belt pitch? Maybe something with belt not matching pulleys well?
If your idler is not a toothed pulley then make sure the belt is turning around idler with its smooth side. Otherwise it would cause small errors with belt pitch period.
Might be also eccentric pulley on extruder. Possibly.
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hercek
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Delta Machines
Most likely reason is wrong PID parameters for heat bed or hot end temperature maintenance. When temperature is fluctuating then also the distance between bed and hot end tip is changing. This change in distance has impact on the actual layer height of the layer currently printed. At the same flow speed that means wider or narrower wall leading to the pattern you see. Check whether the temperatur
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hercek
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Delta Machines
@theliadir:
The scripts are for wxmaxima:
There is no automatic connection of printer output to the scripts. One needs to understand the scripts enough to be able to feed probing data to them manually.
The two most interesting scripts are:
[*] towerErrors - this one enables you to simulate what is the impact of tower position or endstot errors on the first layer
[*] calibration - this allows yo
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hercek
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Delta Machines
You want to use a flying extruder when you intend to print parts which have a lot of isolated isles in their horizontal cuts (i.e. in one layer). That leads to lot of retractions. Each retraction adds some error to the amount of extruded filament especially at high printing speeds. The errors are bigger as bowden gets longer. My first flying extruder had about 7 cm long bowden, I shortened it to
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hercek
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Delta Machines
Here are some really old parts which were printed with the remote extruder and long bowden (about 80 cm). The yellow part was painted with acetone and printed without support. The white part does not have any post-processing. The parts are small, so the maximum printing speed may have been lower to keep the minimum layer time ... probably at 20 seconds. If you want so see some later parts then se
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hercek
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Delta Machines
When I used remote extruder (long bowden) then I needed torque of about 0.6 - 0.9 Nm. My full size Nema17 stepper had torque of 30 Ncm at the current I used (about 1.5A) so I used gearing with about 2.5 ratio. I was using Ø 0.5 mm nozzle and printed at about 120 mm/s, 0.2 mm layer height. The longer the bowden, the smaller the nozzle, the bigger the printing speed, the higher the layer height ...
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hercek
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Delta Machines
Looks like only a bad endstop position on tower A. If the thickness of the first layer changes almost linearly depending on distance from A tower then it is almost for sure bad endstop position on tower A. You can try to adjust it manually with M666 command. I do not use Marlin any more and do not know the meaning of DELTA_ENDSTOP_ADJ.
If you can handle math than this can help you:
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hercek
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Delta Machines
QuoteScintilla
I tried to upload a sketch as usual and all I see in the Pronterface window is hash and symbols and I now have 'An error occurred while loading sketch' in Arduino.
Just try to upload firmware again. Make sure you have selected the right board in arduino ide. Maybe try disconnect a reconnect usb cable. If that does not help then maybe your hardware is faulty.
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hercek
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Delta Machines
QuoteScintilla
As I write, I am watching the printer run through a practice print and I notice that sometimes the print effector moves fairly slowly and smoothly and at other times it is quite abrupt and apparently non-linear in long print moves. It still prints reasonably well now so I'll try to do a full test print and see how it turns out...
This is a feature of Marlin based delta firmwares. T
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hercek
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Delta Machines
Movements can be jittery because of line buffer underflow. Check your delta segments per second. If it is more than 80 then set it to 80 or maybe even 60 if you run your printer slowly (no more than about 50 mm/s).
Anyway a jittery movement is not connected to printer losing precision. A well calibrated printer can lose precision only when some steps are missed (or when the firmware is outright
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hercek
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Delta Machines
It is not a problem of USB cable. If you would have problems with USB cable then the print would completely fail or pause until an USB packet could be successfully sent again. It would not have impact on precision.
Possible reasons:
1) Low current. You can try to increase Vref or decrease maximum acceleration. The reason why low current can cause missed steps at the edges and not at the centre
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hercek
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Delta Machines
Rod length does not have any direct influence on the optimal rod separation. 1/6 proposal is just pulled out of thin air. The important decision is how big platform are you willing to use. The distance of platform middle to an line connecting two corresponding rod ends is equal to the half of horizontal space your printer will be wasting because of the platform size.
The rules are: printer size i
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hercek
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Delta Machines
Put arms in one pair as far away as possible (i.e. as your platform size allows or as much as you are willing to enlarge it). The father away the arms are the less your printer will be sensitive to errors in the arm length and arm mounting point positions on carriages/platform. The bigger distance also provides bigger lever for forces (which means lower stress on the arms and the mounting point l
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hercek
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Delta Machines
It is about as important to have light carriages as it is to have light diagonal rods. Actually you can argue it is more important to have light carriages (especially when the print head is far away from the corresponding tower). On the other side, carriage weight is not important when the print head is near to the corresponding tower. It is harder to accelerate linearly than to accelerate mostly
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hercek
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Delta Machines
Interesting. I have never seen anything like this. Kind of looks like additional z-height added (z-hop) when moving the head. This is a slicer setting. But it is supposed to be added only for travel moves longer than e.g. 2 mm while it looks like it is added between all segments on your video. Also when z-hop is enabled then it is active on the first layer too ... well, at least i think so.
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hercek
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Delta Machines
If you have a schematic for your LCD then you can check with ohm meter wither the button press will short the appropriate pins on the cable/connector. The pins of interest are identified from the schematic. Then you can check the pins.h file of your firmware to check that the proper MCU pin is assigned to the button functionality in the firmware.
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hercek
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Delta Machines
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Pages: 12345