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GreenMaker V1.0 - Advanced 3D printer

szymon122 4749 27
This content has been translated » The original version can be found here
  • GreenMaker V1.0 - Advanced 3D printer
    At the beginning, I would like to thank everyone who did not believe in me - my strength in you! :D

    Table of Contents:

    [line: 2f4bfa70a4]
    1. Introduction
    2. Assumptions
    3. Mechanics of movement
    4. Why not CoreXY?
    5. The final shape of the "cross"
    6. Toolchange - a system of variable tools
    7. Parking of warheads
    8. Z axis
    9. The table
    10. Table clamping system
    11. Main and subframe and its reinforcements, chamber
    12. Electronics
    13. Compressed air cooling system for printout
    XX. What is he currently working on?


    1. Introduction
    [line: 2f4bfa70a4]
    My fun with 3D printing began with the purchase of the Ender 5 Plus printer, which itself is very correct and I recommend it for the beginning, but with time, when I learned about its advantages and disadvantages, I started to redo it, it started with electronics, then linear guides and in the end, I am satisfied with the results, but the construction itself has become a limitation.

    In the meantime, as part of one of the subjects at university, I got to know the 3D design program - SOLIDWORKS and I decided that I want to learn how to use it, but for this I need motivation - so I will design a 3D printer as I would like to have.
    The project started around mid-2020.

    2. Assumptions
    [line: 2f4bfa70a4]
    [letter = 1: 2f4bfa70a4]
    [*: 2f4bfa70a4] Working area 400x400x400
    [*: 2f4bfa70a4] Two extruders
    [*: 2f4bfa70a4] System of interchangeable tools (development issue)
    [*: 2f4bfa70a4] Cartesian mechanics - not CoreXY (I'll explain why below)
    [*: 2f4bfa70a4] Zero rolls - only MGN12 linear guides
    [*: 2f4bfa70a4] 230V table
    [*: 2f4bfa70a4] Chamber
    [*: 2f4bfa70a4] Controlled by Raspberry Pi 4
    [*: 2f4bfa70a4] Printing speed> 300mm / s
    [*: 2f4bfa70a4] Possibly light head
    [/ letter: about: 2f4bfa70a4]

    3. Mechanics of movement
    [line: 2f4bfa70a4]
    Initially, the mechanics were to be the same as in UltiMaker - linear shafts with a diameter of 8 mm forming a cross and a Chimera hotend in the center, but the first static analyzes in SOLIDWORKS showed that the 60 cm long linear shafts are too flexible and under a test load of 300 g in the middle they will bend by over 0.2mm and this is one layer - unacceptable. The solution was simple - use MGN12 linear guides instead of shafts.
    This is how the first version was created:
    GreenMaker V1.0 - Advanced 3D printerGreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer
    (Here the arrows show how the motion of one axis is "transmitted". The other is identical, rotated by 90 °).


    Link


    4. Why not CoreXY?
    [line: 2f4bfa70a4]
    The whole time I had a dilemma whether I was doing right with Cartesian mechanics instead of CoreXY. I was effectively deterred from CoreXY by how precisely a system must be designed in order for it to work precisely. In addition, CoreXY operates on straps, which in my case would be many meters. Such strips are subject to temperature which makes the strips susceptible to stretching under the influence of acceleration. Besides, the stripes require perfectly parallel guidance - without it the circle becomes an oval which is difficult to eliminate and detect.
    I found the Cartesian system to be more predictable and simpler to design.


    5. The final shape of the "cross"
    [line: 2f4bfa70a4]
    This stage caused me a lot of problems, because since the cross is not in the middle, there is no place for the printhead :D
    GreenMaker V1.0 - Advanced 3D printer
    This photo best shows what the problem is - If you screw the hotend, it's not a problem, you need to route the filament supply tubes somehow.

    I solved this by rotating the guides by 90 °, which allowed me to use an element that connects it in the form of an angle bar and moving the guide carriages apart, thanks to which I have an empty space above the extruder, which allowed for free routing of the bowden tubes supplying the filament.

    GreenMaker V1.0 - Advanced 3D printer
    This photo shows what the next point will be about :D but earlier
    I would like to add that my friends told me that at speeds> 300mm / s, which I plan to achieve, the guides themselves may not be stiff enough, so the "cross" has been reinforced with Tslot 2020 profiles.
    GreenMaker V1.0 - Advanced 3D printer
    This solved another problem that I am the cause of :D
    When ordering linear guides, instead of ordering 7x 500mm + 2x 600mm, I ordered 9x 500mm. The profile allowed me to screw the guides in the middle and the trolleys do not reach its end anyway.


    6. Toolchange - a system of variable tools
    [line: 2f4bfa70a4]
    It is one of the elements of this printer that appeared during the rebuilding of the head. I found that if there is a possibility then why not try it :D There are few printers that can do this.
    It is difficult to find information on how to do it, what are the advantages and disadvantages of a given solution, etc.
    In fact, one solution dominates the market - e3d tool changer

    When it comes to positioning, the only sensible solution is the so-called Kinematic Coupling (I have no idea what to call it in Polish).
    This is based on six rollers (DIN 7 cylindrical pins) and three balls.
    As a result, when one part is pressed against the other, they are always perfectly in the same position in relation to each other.

    Another issue was locking the tool in the holder (locking and tightening). Initially, I planned a pulley and line system as in the video below:

    Link

    GreenMaker V1.0 - Advanced 3D printer
    In the end it turned out to be a bit overcomplicated and I will eventually use a modeling servo. It can be controlled directly from the motherboard, is small and light, knows its position and has high torque.

    GreenMaker V1.0 - Advanced 3D printer
    Unfortunately, the 2020 profile added to the guide prevented me from mounting the servo as in the photo above, so
    I had to add a small angular gear - initially I planned to print it, but in such small details 3D printing is not very precise, but it turned out that the LEGO 6589 rack fits perfectly.
    The servo mounting will design later, after starting the printer in the basic version.
    GreenMaker V1.0 - Advanced 3D printer

    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer

    A big unknown for me is the system of tightening the head to the handle.
    A friend from the Russian 3D printing community helped me a lot.
    The photo below shows that the disc has two double helix surfaces. At the moment of rotation, the rod simultaneously tightens and locks the tool.
    GreenMaker V1.0 - Advanced 3D printer
    Can the servo do it? I do not know
    If you have any idea how to solve it, I will be grateful!

    What are you planning for the tools?
    [letter: 2f4bfa70a4]
    [*: 2f4bfa70a4] Chimera hotend
    [*: 2f4bfa70a4] 2.5W laser
    [*: 2f4bfa70a4] Pisak
    [*: 2f4bfa70a4] Spindle (something small, mainly for PCB milling)
    [*: 2f4bfa70a4] It is possible that I will add a hotend with a large nozzle, e.g. 0.8mm to fillings, internal wall contours, etc.
    [/ letter: u: 2f4bfa70a4]

    7. Parking of warheads
    [line: 2f4bfa70a4]
    This is the part that I have temporarily stopped developing, so far I have an idea for it, but the success of the previous points determines what the final shape will be.
    On the back of each head, he will attach a printed element having two spacer-shaped holes that are used to attach the PCBs to the housings. Two such rods will be placed in the parking lot and the head will rest on them.
    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer


    Link


    8. Z axis
    [line: 2f4bfa70a4]
    In my printer, the Z axis consists of three independent "systems" - Z0, Z1, Z2.
    Each of them consists of a Tr8x8 trapezoidal screw with a length of 500mm, a Nema17 motor, a backlash-free nut and a 500mm MGN12 linear guide.
    The motor and bolt connection is realized with a GT2 belt (identical to the X and Y axes), eliminating the clutches that are often the source of the axial runout.

    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer

    Originally I only gave one KP08 bearing, but it was rightly stated that the belt tension would cause the bolt to bend, so I added a second bearing above the sprocket.

    This allows me to rigidly attach the table and only electronic leveling - based on BLTouch, i.e. a touch sensor based on a hall sensor and a magnet at the end of the rod. This gives perfect accuracy and repeatability.

    9. The table
    [line: 2f4bfa70a4]
    The table was cut for me from the G.AL C250 aluminum plate, i.e. the cast aluminum AW 5083, milled on both sides and thermally stress relieved. As a result, warping after heating should be as small as possible in relation to rolled aluminum.
    The table is 440 x 440 mm and 8 mm thick.
    The weight of the aluminum itself is about 4.5 kg, I estimate the top tempered glass and the weight of the entire table at 6 kg.

    Below are the deformation analyzes

    [letter: 2f4bfa70a4]
    [*: 2f4bfa70a4] Load: gravity
    GreenMaker V1.0 - Advanced 3D printer
    [*: 2f4bfa70a4] Load: gravity + 1kg with dimensions of 10x10cm (print simulation)
    GreenMaker V1.0 - Advanced 3D printer
    [*: 2f4bfa70a4] Load: gravity + 1kg with dimensions of 10x10cm + heating to 100 ° C
    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer
    [/ letter: u: 2f4bfa70a4]

    The table is of course heated. At the bottom there is a silicone heater with dimensions of 400x400mm and a power of 1300W, powered by 230V. The table is intentionally larger in order to be able to attach a frame made of 2020 profiles around the perimeter, if necessary.

    Below are tests performed with a Fluke Ti95 thermal imaging camera showing how the temperature spreads. I stuck a paper tape on the table, because the table effectively deflects radiation and is invisible to the thermal imaging camera.
    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printerGreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer

    10. Table clamping system
    [line: 2f4bfa70a4]
    Due to the fact that the table will be leveled electronically, it must be able to rotate in relation to each of the Z axis, theoretically three ball joints are enough, but in practice heating the table from 20 ° C to 100 ° C will expand its dimensions in X and Y dimensions by 0.8mm. If a rigid clamp is used, the increase in dimensions will cause the table to warp.

    For this reason, I used a system similar to the head mounting, i.e. also six rollers and three balls.
    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer
    Thanks to this, I have the possibility of rotation and in the case of an increase in temperature, the balls will simply "spread" on the rollers.

    Another advantage of this solution is the possibility of tilting the table and I am interested in the vision of "non planar" printing or, for example, reducing the number of supports, because the overhang angle can be reduced by tilting the table.

    Link


    There is only one problem, I marked a dot in the center of the table and an identical dot in the center of the frame above the table.
    When the table is tilted, the dots begin to "spread" in the X and Y axes up to about 2mm.
    Do you have a problem, can it be solved somehow?


    11. Main and subframe and its reinforcements, chamber
    [line: 2f4bfa70a4]
    Initially, I planned to use Vslot 2020 profiles, but then it turned out that Tslot profiles are cheaper and more durable.
    The external dimensions of the printer are 750x640x640mm.
    The total weight according to SOLIDWORKS is 40.3 kg, but I do not have any bolts (I added maybe 50 bolts and yet the assembly has 997 components at the moment), so the final weight will be around 50 kg.

    GreenMaker V1.0 - Advanced 3D printer

    Due to the relatively thin aluminum profiles, each corner has been reinforced with a 3mm thick black steel corner, which will be laser cut and bent with a CNC bending machine, just like aluminum parts (movable parts are aluminum to reduce weight and the rest is steel)

    Chamber:
    The chamber in the 3D printer is designed to provide a high temperature that surrounds the printout in order to minimize material shrinkage, which causes cracking and warping of the elements. The heat source in the chamber is a silicone heater attached to the table. The walls of the chamber are planned to be made of 5 mm thick foamed polycarbonate plates, which insulates heat well, and I will additionally cover it with an acoustic sponge from the inside, which will soundproof the whole thing and improve thermal insulation.
    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer

    12. Electronics
    [line: 2f4bfa70a4]
    The electronics are divided into two boxes, one 230V and the other with "logic".

    Inside the first one there are overcurrent protections for the entire table, the table and the 24V 300W buffer power supply, relays responsible for turning off the electronics from the Raspberry Pi level and the second responsible for the emergency button (mushroom), the 24V 0.5A standby power supply supporting the relay from the mushroom and the SSR relay controlling the table heater .

    The second box only has a voltage of 24V and inside there is the SKR 1.4 TURBO main board with the BTT EXP-MOT module. Such a set allows you to control 8 stepper motors, but in this case 7 motors were used (3x Z, X, Y + 2 extruders) and each of them has a TMC2209 driver. The X and Y axis motors have a rotation angle of 0.9 ° which is 400 steps, the rest is the standard 1.8 °.
    These controllers allow you to return to the zero position (homing) using the method called "sensorless homing", i.e. the lack of confirmation of the correct step by the controller, because the motor has reached the end position and pressed against the frame.
    I do not know whether I will use this function or use optical limit switches.

    In the meantime, I managed to buy the SKR GTR board, which is based on the STM32F407IGT6 chip and I will probably use it because it has several times more GPIO than that board and I lacked, among other things, one PWM port for servo control and the additional BTT M5 module allows for total control 11 engines.

    The board will be controlled by Klipper Firmware, which is probably the only one suitable for such an extensive machine.

    In order to function, apart from the "executive" board, the klipper needs a computing part, which will be performed by the Raspberry Pi 4 in the 4GB version of the framework.
    A 5 "touch display is connected to the RPi via the DSI socket and the RPi itself is connected to the motherboard via UART.

    One of the interesting functions of the clipper is, for example, the ADXL345 accelerometer operation and the measurement of head vibration and resonance frequency as well as the selection of acceleration in such a way as not to lead to it.
    GreenMaker V1.0 - Advanced 3D printer

    As for the firmware inside the RPi, it is Mainsail + Fluidd graphic overlay.

    As the sockets connecting the second box with the world, I used the GX12 and GX16 sockets for the accelerometer. This allows for quick disconnection of cables and replacement of a given component.

    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer

    13. Compressed air cooling system for printout
    [line: 2f4bfa70a4]

    Due to the small dimensions of the head (45x45mm), I was unable to fit the 5015 fan without excessively increasing the external dimensions.
    I decided to move the "drive" outside the head and use an air pump called berd-air, which I will place next to the electronics.
    GreenMaker V1.0 - Advanced 3D printer
    It is a diaphragm air pump powered by a 555 24V engine with a capacity of 15L / min. Thanks to this, I can only bring a silicone hose with a diameter of ~ 6mm to the head.

    Due to the fact that compressed air will be useful not only for cooling the print, but also for removing smoke in the case of laser engraving of wood, I am considering making a servo-controlled distributor so as to be able to supply air to the heads that need it and control it to which at a given moment air is supplied.

    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer
    It is a copper tube with an outer diameter of 6.4 mm and a wall thickness of 0.8 mm, used in air conditioning systems.
    Anyone have an idea how to bend it at such sharp angles without kinking?
    Heat it with a burner?
    Pour soapy water and freeze? (I did it, but with thicker ones)

    The ends will of course be sealed and the air outlet will be only 2mm diameter tubes.


    Link


    XX. What is he currently working on?
    [line: 2f4bfa70a4]
    Finally, after many months of designing and calculating, I moved to construction.
    At the moment, I have assembled the frame and ordered laser cut parts.
    The rest of the components are waiting in cardboard boxes for assembly, but I am stopped by the lack of cut elements.

    Besides, I am finishing the electronics housings

    GreenMaker V1.0 - Advanced 3D printer


    As the work progresses, I will update this description, besides, I have for sure forgotten many things at the moment, so I encourage you to check if there is any EDIT ;)

    If any of you know the solutions to problems with bold I am asking for information.

    Feel free to discuss, constructive criticism, advice and tips.

    Cool! Ranking DIY
    Can you write similar article? Send message to me and you will get SD card 64GB.
    About Author
    szymon122
    Level 38  
    Offline 
    szymon122 wrote 3869 posts with rating 536, helped 282 times. Live in city Konin. Been with us since 2009 year.
  • #2
    hacker_ice

    Level 24  
    Very nice workmanship and idea :) Did you think about the costs, how would it go for the finished printer plus other heads? I understand the whole controlled by one program plus automatic change of heads as in cnc?
  • #3
    szymon122
    Level 38  
    hacker_ice wrote:
    you thought about the costs as it would go for the finished printer

    As soon as I am satisfied with the results, I plan to start selling the printer as well as the kit for its construction.

    The interest is considerable, because the presented printer, in my opinion, fills the gap between amateur printers for PLN 3,000 and professional ones, the cost of which starts from PLN 20,000. Officially, I can only say this at the moment. Feel free to contact me using a private message, there I will try to specify the range of amounts at which it targets.

    hacker_ice wrote:
    I understand the whole controlled by one program plus automatic change of heads as in cnc?

    It's a bit not quite how it works.
    Of course, the change of heads is automatic, it happens thanks to gcode macros, ie entering a command from the outside, eg "T2", starts a macro of a series of gcode commands, as a result of which tool A is put away and the downloaded tool B. These macros are "inside" the printer.

    Nevertheless, as in any 3D printer, its control is done with the help of gcode, so if you want to print an object, you need to change its spatial version with the help of "slicer" software for a set of commands.
  • #4
    Lukasr29
    Level 20  
    In my opinion - it will not be cheap ;) The price of the materials themselves is quite easy to determine, a lot depends on where you buy. From my experience with MGN12 and this family of rails - recently it was different with the quality from CN, some trolleys, even after thorough washing and lubrication, did not give smooth feed ... (the balls on one side slipped or cut, ordered back in 2019 worked perfectly without no further ado)
    The printer itself - the design seems to be really thought out, you can see that a lot has been thought out and conclusions were drawn from the ready-made designs (I myself have a milling machine in which the original parts are the driver, stepper motors and a piece of the table base ... all the rest changed ... the next step is new construction ...)
    From the theme of "dots" and its synchronization with the center of the structure - the "dot" on the table must be the focal point (balancing the table according to its middle point), i.e. when one rafter flies down, the other two on the opposite side must rise by the same distance , and it is simple as long as the slanting table does not appear diagonally ;)

    Edit:
    It seems to me that the XY drive will be implemented on strips, the aforementioned temperature is important, the same speed of the feed, at 30cm / s the strips will spring up strongly, I recommend looking for YT printer acceleration tests to 800mm / s (nothing came of it ;) but already at 400mm / s distortions caused by elasticity of the belts could be seen), it should be taken into account that pick & place machines have belts with a width of several cm, where the loads may be comparable, but the speeds and length of the belt are much smaller,
  • #5
    szymon122
    Level 38  
    Lukasr29 wrote:
    at 30cm / s the strips will spring strongly, I recommend looking for YT printer acceleration tests up to 800mm / s (nothing came of it

    Honestly, every printer I know is based on stripes.
    In most designs, the X and Y axis is moved by one GT2 6mm belt, I will have two such belts in parallel (not counting the small 200mm drive loop). Fortunately, the way they are guided allows for a simple replacement with the 10mm version.

    Lukasr29 wrote:
    From my experience with the MGN12 and this family of rails - lately it has been different with quality with CN

    I agree, I had a lot of talks with sellers, and in the end it turned out that there are only a few "real" producers, the rest are middlemen. I ordered directly from a manufacturer in China, the quality is really great.

    Lukasr29 wrote:
    I have a milling machine myself, in which the original parts are a driver, stepper motors and a piece of the table base ... all the rest changed ... the next step is a new construction ...)

    I found that, like me, many people are just tired of having to buy a factory printer and have to replace half of its components right away, and ultimately the price exceeds the value of the printer. I immediately preferred to do something right ;)
  • #6
    arkady25
    Level 16  
    szymon122 wrote:
    ... When the table is tilted, the dots begin to "diverge" in the X and Y axes up to about 2mm. ...


    In my opinion, you must take into account that the table surface does not pass through the pivot points of the table when tilting it. And this has to be calculated when printing.
    Note that such a point on the top surface of the printed item will move more and more with increasing print height.

    Arkady25
  • #7
    Dariusz Goliński
    Level 22  
    That little friend saw.
    Printers with interchangeable heads - 3dgence
    Ball screw printers - dragon3d
  • #8
    szymon122
    Level 38  
    Dariusz Goliński wrote:
    Printers with interchangeable heads - 3dgence

    GreenMaker V1.0 - Advanced 3D printer GreenMaker V1.0 - Advanced 3D printer
    You'll admit there are two different "definitions" of interchangeable heads here. In the printer you mentioned, we can change the hotend without the use of tools, that is, we stop the printout, open the cover, use the "PUSH T1" lever to unlock the heads, use it and insert another one with a different diameter, for example.
    But it will not do itself automatically, we only have hotends, not other types of tools, the number of tools is constant, i.e. there are two hotends going with the head all the time, I can go to the parking lot, put the heads back and get another one, I estimate that it will fit I have 5-6 heads in the parking lot, but I already had a question about the possibility of making a "carousel" and it is possible, but I do not see any use.

    Added after 18 [minutes]:

    Dariusz Goliński wrote:
    Ball screw printers - dragon3d

    Here I am right, I have not seen this construction before, which is a pity, because it is our domestic production.

    Ball screws are a very interesting solution for the drive, because they are relatively cheap, they simplify the structure and allow for very large working areas, which the manufacturer effectively used.

    Nevertheless, I am curious about the rolling resistance and the inertia of such a screw, you can see that the motors used in this design are NEMA23. The manufacturer talks about the possibility of fast printing, I wonder what speed and acceleration he can get.

    Added after 5 [hours] 20 [minutes]:

    EDIT 02/27/2021 15:12 - I added a description of the compressed air cooling system for the printout.
  • #9
    TvWidget
    Level 35  
    szymon122 wrote:
    Nevertheless, I am curious about the rolling resistance and the inertia of such a screw, you can see that the motors used in this design are NEMA23. The manufacturer talks about the possibility of fast printing, I wonder what speed and acceleration he can get.

    Ball screws were used in SMT machines of this type https://www.youtube.com/watch?v=xNRAFwfCHv0. They are powered by small Panasonic AC motors (0.64 Nm). The traversing speed is really impressive. The entire structure, however, weighs well over 200 kg.
  • #10
    szymon122
    Level 38  
    TvWidget wrote:
    The traversing speed is really impressive.

    I am really surprised by the speed of movement of this machine!
    Honestly, I will consider these propellers to drive future designs.

    My motors are 0.26Nm. I was able to find the servos used in the machine from the video. Unfortunately, the price is also good and I do not know if it includes the driver :D

    https://tinyurl.com/napedserwo
  • #12
    Dariusz Goliński
    Level 22  
    I have Hbots, Atmata, and one Dragoon at work. If you want to see something, let me know. Hbot, Dragon and 3D gence are all Polish constructions. But dragon, despite the use of ball screws, is rather the worst choice because the company is poor and the printer is poorly made. I have a Dragon with a working area of 500 x 700 x 500 and an aluminum table. 4 peasants have something to carry if it needs to be moved.
    You plan to make a heated table with a glass plate. This is how habots have and there the leveling of the table is done with the use of strain gauges.
  • #13
    szymon122
    Level 38  
    Dariusz Goliński wrote:
    You plan to make a heated table with a glass plate.

    Many people suggested that I stick a PEI sheet directly to the aluminum plate, but I was not convinced by this idea. Due to the fact that I intend to use a 100% laser head (I have a 2.5W laser, mainly for engraving plywood), I would rather not put the workpiece on PEI, because the random laser beam will effectively damage it.
    So I'm going to use tempered glass (probably 4mm) and stick PEI on the glass pane (as I find 400x400mm) or print directly on the glass. Besides, plywood sheet for milling and engraving.

    Dariusz Goliński wrote:
    there the leveling of the table is carried out with the use of strain gauges

    I thought about it, but once I found information that over time such a strain gauge begins to lose its properties and shows less and less pressure. BLTouch has no mechanical elements (apart from the rod, which only touches the table under its own weight).

    Dariusz Goliński wrote:
    If you want to see something, let me know.

    Do you have any info on the speed and acceleration the dragon achieves?
    What's the ball screw there? Maybe it has a marking somewhere, or at least the diameter.
    I can see clearly from the pictures that the motors are NEMA23? So 56mm wide. Do you have the option to make / write down their model?
    Which of these printers has the best hotend?
  • #14
    Dariusz Goliński
    Level 22  
    As for strain gauges, these printers have been tortured almost continuously (even on weekends) for 3 years and there was no failure. There is boron glass in the habots, on which a piece of Kapton tape is glued. As for the screws, it will not be a symbol, but I can write down symbols from the bearings. I'll measure the engines and give it to you.
    There is no perfect printer. Each of them has its advantages and disadvantages. I know from experience that the less overcomplicated hot-end and the better access to it, the better. Hbot has a hot-end partly made of PEEK. There is no need to cool the heat sink. The Atmat is completely enclosed, a flat hot-end with a fan, and the dragon is a classic V6, but it was rebuilt by me because the original had hopeless access, but it is also mostly loosening on the thermal barrier.
    As for leveling, the H-bot uses strain gauges, the dragon has an inductive sensor with a longer range and the atma bltoucz which I have already replaced 4 times. This movable plastic tip keeps breaking off. I will use it too, but with a metal tip.
  • #15
    szymon122
    Level 38  
    Dariusz Goliński wrote:
    This movable plastic tip keeps breaking off. I will use it too, but with a metal tip.

    Do you have any bearing on a metal pin? Unfortunately I can't find anything on sale.

    I once replaced the pin (ordinary, plastic), but only through my own fault, I changed the mounting and forgot to adjust the height, it turned out that the hidden pin was a fraction of a millimeter below the nozzle and it bent slightly during calibration (it can be saved, but I preferred to replace) .
  • #16
    Dariusz Goliński
    Level 22  
    These pins can be bought for pennies on Ali ... and a little more expensive on Ale .......
    Once upon a time I found on Ale ....... but now I can't see. But they do appear.
  • #17
    kojderek01
    Level 2  
    Great design.
    My advice is only about electronics. I would avoid SKR products with such advanced mechanics. The support from the producer ends with the typical Chinese "Sorry My Friend". I am an unhappy owner of SKR PRO 1.1 and it is a torment. It seems to have a lot of UART and SPI, but you can't use them all. The manufacturer has put on the board a standard USB socket, unfortunately not available in the Marlin 2.0 software, the possibility of connecting WiFI, but at the cost of HOST USB connection, so either a cable or wifi. Interface wifi is ESP3D very similar to pronterface but hangs a lot to write more. I think that for such a serious design, Duet2 WIFI or Duet 3 will be a much better choice, it is a British design with excellent support from the manufacturer, well described by the user community and developers. It runs on Reprap software and has a very intuitive configuration wizard. I recommend buying the original, then you have full support from producers who really have an individual approach to user problems but sometimes ask for a serial number that Chinese clones do not have. Yes, the Duet is more expensive than the SKR GTR, but with such a printer structure, I would not save on reliable control. I see you're planning three motors for the Z axis to perfectly level the table instead of using software to compensate for curvature. I did not use it in my design, but when analyzing the instruction, such a configuration of the z-axis appears as an example when leveling the table.
    Regards.
  • #18
    szymon122
    Level 38  
    kojderek01 wrote:
    The manufacturer has placed a standard USB socket on the board, unfortunately not available in the Marlin 2.0 software

    Literally yesterday a version of Marlin with usb support appeared ;)
    I invite you to priv, I will send you the contact details.

    Nevertheless, it is a very archaic project, most of its functions are written to work on 8-bit discs and cannot take advantage of the possibilities offered by a modern disc.

    I am going to use Klipper firmware, I have already done my first tests (the thermal camera was doing PID tests on Klipper).

    kojderek01 wrote:
    I believe that Duet2 WIFI or Duet 3 will be a much better choice for such a serious design

    The advantage of DUET discs is the software that is available on the Internet and can be uploaded to the SKR disc, so I don't see any point in paying that much for the disc.
  • #19
    Dariusz Goliński
    Level 22  
    And I checked.
    The nut on the ball screw has the symbol: HIWIN S1600VE-1 082
    The engines are: MICROCON SX23-1414
    I am missing something in your printer. I assumed that (I don't know if it is right) you plan to build the machine in. I don't see the description of the machine's ventilation. And how to install it, if you want to heat the chamber, if you want to work with ABS. Well, I do not know what materials you are setting yourself up for, but if you plan such a serious construction, the chamber for pre-drying and heating the filament would be useful.
  • #20
    szymon122
    Level 38  
    Dariusz Goliński wrote:
    I assumed that (I don't know if it is right) you plan to build the machine in.

    Item 11 describes how he plans to make a chamber. In most of the photos I have hidden covers, because even with the transparency on, they make it difficult to see the structure.

    Dariusz Goliński wrote:
    Well, I do not know what materials you are setting yourself up for, but if you plan such a serious construction, the chamber for pre-drying and heating the filament would be useful.

    The filament will be in the subframe (side). There will be a lot of electronics there, which of course heats up. The housings will have fans cooling, for example, motor drivers, but the housing itself will be rather tight, which should help keep the temperature inside, say 30 degrees, which should help the filament dry.
    But I don't know if the temperature alone is enough or if the air needs to be replaced.

    Dariusz Goliński wrote:
    The engines are: MICROCON SX23-1414

    As I thought - very powerful 1.4Nm engines. This may be a necessary condition in the case of a drive based on ball screws in the X and Y axes.
  • #21
    Dariusz Goliński
    Level 22  
    But the chamber itself will not have a heater and temperature stabilization?
    Do I see well that you have extrusion motors with the filament?
  • #22
    szymon122
    Level 38  
    Dariusz Goliński wrote:
    But the chamber itself will not have a heater and temperature stabilization?
    With the current printer, I have a chamber with a similar capacity and the heater of the table itself (350x350) heats it to about 40 ° C in the case of ABS printing, i.e. 100 ° C on the table.
    There, the limitation is 2mm plexiglass from which I made the chamber, it insulates on average and you can feel the temperature on the outer wall. Now I'm going to use foamed polycarbonate which should handle it better.

    Dariusz Goliński wrote:
    Do I see well that you have extrusion motors with the filament?

    Yes. What's the problem?
  • #23
    maxipug
    Level 12  
    I see that the https://hevort.com project is in use, I recommend that you familiarize yourself with the problem of propellers and their quality.
    The table clamping has been redesigned several times due to non-alignment
  • #24
    szymon122
    Level 38  
    maxipug wrote:
    I see that the https://hevort.com project is in use, I recommend that you familiarize yourself with the problem of propellers and their quality.

    I don't understand the comment a bit.
    What does hevort have to my design? I have worked with them a lot, but this is not the project :)

    maxipug wrote:
    The table clamping has been redesigned several times due to non-alignment

    Their table mounting has a different form and assumptions. We will see how it will be in my case.
  • #25
    Dariusz Goliński
    Level 22  
    Problem with poor extrusion control
  • #26
    ZaQ_1
    Level 8  
    Since the author wants to print 300mm / s, he does not have much choice and must give bowden due to the moving mass. Unless he would drive the extruder with a flexible shaft and put the motor on the frame. But that would be a topic in itself worth a project of its own.
  • #27
    szymon122
    Level 38  
    ZaQ_1 wrote:
    Unless he would drive the extruder with a flexible shaft and put the motor on the frame. But that would be a topic in itself worth a project of its own.

    Rather, it might not work. I mean, I've seen such designs, but I don't know what the shortening of the spring and its elasticity are about it. Most of the extruder's movements are a fraction of a turn and are very quick. I feel like the spring would "smooth out" such movements.

    A better solution is an extruder motor connected by a belt to the extruder. The motor is on the Y axis (it moves with it) and only relieves one axis, but that's good too.

    But in my case, the frame-mounted extruders are designed to reduce the moving mass. One extruder with a motor is about 200g ;)
  • #28
    szymon122
    Level 38  
    Welcome!
    I haven't been here for a long time, but that doesn't mean the work has stopped. Unfortunately, this was due to delays in the delivery of components. Yesterday I was able to launch the website:
    www.greenmaker3d.wordpress.com " target="_blank" rel="noopener nofollow ugc" data-caption="" class="postlink "> www.greenmaker3d.wordpress.com
    I invite you to it, I described the design part there and in the form of a blog I publish the progress of work on the printer ;)

    At the same time, a Facebook page was launched @ GreenMaker3D to which I also invite you.