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At wit's end

Discussion in 'Control Software' started by MB460, Nov 5, 2019.

  1. MB460

    MB460 New
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    Hey guys.

    Going crazy trying to figure this out.

    I'm done for the night and I'm typing this on my phone. I don't have code examples. If I didnt step away from the machine I was liable to push it off of the table and start sledgehammering it.

    I'll provide code soon.

    I need to know the -exact- procedure for Zeroing this machine.

    I have a workbee 1510, I'm using the control software that comes with it, and I'm making my cam in fusion. I have the grbl patch that is supposed to make it work. Some operations work... most dont...

    When I home all, that works.
    Then i zero out the machine manually. I usually go off to one side . Then bump the tool against the stock, raise Z, then divide the width of the tool by 2 to figure out X 0 then i set it by clicking the button. I do the same fir Y. Then I lower z until it touches.

    That's all the instructions and videos say to do "you're good to go" hit the button and it PLUNGES and drags the tool through the stock, them plunges even deeper to start a cut, then I stop the thing, hit GO HOME and it hits the Z limit, and goes more or less back to 000 but not exactly then I have to re zero it.

    You'll have to take my word for it at the moment, but the code does not say to plunge... however, I noticed that theres a drop down. It says go to work area zero,, or go to (some other) zero. One is g53. If i tell it to go to the zero i created it generally does, half of the time. If i tell it go to to g53 home it will run away and hit z limits and XY would stop somewhere in alaska if i let the machine go on... I'm in Texas if that gives you an idea...

    How the crap do you zero the g53? Is that causing these issues potentially?

    I have checked and re checked and triple checked and then did it again the models in fusion. Even the fusion simulations raise the tool. Not lower...

    Furthermore, I flipped my piece over and tried to cut the back side and the first cut was INCHES off of where it should be. I used a squared piece of stock, that fit exactly into the same clamps, used the same axis point etc. I guess that's a different thread though.
    PLEASE... help.

    And please dont say "well blah blah without code we cant help' I'll get you the code asap... in incredibly frustrated. this machine cost a good chunk of money and a lot of my time and it needs to start producing $$$. I need help figuring this out. Please help. Also, if you're versed in fusion, that would be ideal, giving examples in a different software would be like giving instructions in russian to me. The only thing I know about g-code is from the grbl pdf with codes that I downloaded. Please do not assume that I know anything at all about what in doing. Explain it to me as if I didnt know what a computer was. I wont be offended. Be detailed, there is probably 1 small step I'm missing.

    Thanks in advance.
     

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  2. David the swarfer

    David the swarfer OpenBuilds Team
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    I am pretty sure this covers it....
    Not sure where to put work piece

    but let me make sure of a few things....

    So, to confirm, you have home switches and homing works. AND Z home is high up above the work.

    The homing operation is what 'sets G53'. G53 is the Machine Co-ordinate System. everything the machine does is relative to this position.
    so you bump the tool on the side and click 'set zero' for that axis and then move it bitdiam/2 and click 'set zero' again. This works for X and Y.

    then for Z you touch the end of the tool to the top of the raw material and click 'set zero Z'.

    that is all correct, so long as the surfaces you touched are also the surfaces you designated in fusion360 as being aligned with the 0,0,0 reference point for this CAM operation.....

    this indicates that the place you are telling the machine is 'part zero' is not the same place that fusion thinks it is on the raw material.
    In the Fusion post there are edit boxes for entering an offset. Because Z = 0 is actually against the limit switch (set by homing) if you do G53 G0 Z0 it will hit the switch and you should get a hard limit alarm.
    Same for X and Y. The offsets are there to prevent this, if you enter -10 for Z then the gcode generated will be something like (assuming millimeter mode!)
    G53 G0 Z-10
    which will move Z to the high end of its travel less 10mm. This is an industry standard 'safety move', ie move Z far away from the work before moving X and Y so that the tool does not hit any clamps etc.
    Homing sets G53 , the Machine Co-ordinate System (MCS).
    clicking the 'set zero' buttons set the Work Co-ordinate System (WCS) which defaults to G54 which in the Fusion setup is WCS=1. Best you check that, seems to me you are setting up the machine in G54 and then the Gcode tries to use G55 or some other WCS.
     
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  3. David the swarfer

    David the swarfer OpenBuilds Team
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    This may be a better explanation:
     
  4. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    WSo
    Sounds like you are forgetting to click SETZERO after jogging to where ZERO is. If you dont SETZERO the DROs arent set to 0 where you are so moves are relative to where 0 was last set, not where you are
     
  5. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    is worth a watch too, shows the correct procedure
     
  6. MB460

    MB460 New
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    Thanks! I'll give this a much better response soon. Getting ready for the day. But it all makes sense so far.

    Just to verify, g53 z0 is from the limit switch and is opposite (reverse) of standard work Z. This makes sense as to why when I set it for 15 it dug even deeper, and them i hit a negative number it alarmed out.

    For reference sake, the work piece is 1.75" thick, give or take a little bit, and with a bit, set in a way to cut through it, I pretty much have no room on the Z for extra movement, or at least not as much as it wants. So I've had to adjust the tool to make it shorter and cut half way through the stock.

    I'll verify thicknesses on the stock and model as well. Thanks for the awesome reply, I'll get back to you asap after reviewing the videos that everyone sent and further testing. But this does make sense.

    Also, the z limit is as far as it can possibly be, since the question was asked. The. X and y are far enough away to where the tool can never make contact with the machine's frame on the homing side. I need to add limit switches to the opposite side for safety.

     
  7. MB460

    MB460 New
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    Btw when I set home, and home all using the home all button it goes to the correct home. If I use the drop down where I can go to the work zero or machine zero, machine zero doesnt go to the machine home position, it goes crazy and goes wherever it wants to go. That's what got me wondering how to set it.
     
  8. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    Depends: if your switches are at the far (positive side) of the axes, gnea/grbl need to be setup too

    See gnea/grbl for more details

    The Grbl Wiki is a must-read to understand it all :)
     
  9. MB460

    MB460 New
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    Thanks. I will give that a read as well. I was under the (possibly false) assumption that by selecting the machine in the openbuilds software setup, that this was done automatically. (?)
     
  10. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    If you did, then yes. But still a little learning curve, watch the video linked above to see the proper procedure
     
  11. MB460

    MB460 New
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    Just finished reading the grbl wiki article listed above, getting to videos now :) thx
     
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  12. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    LinuxCNC "G-Code" Quick Reference is another good reference to bookmark. Not all commands are supported by Grbl, but the ones that are - comply with the LinuxCNC standard, so good reference. Grbl lists which Gcodes it supports, on the homepage of the Wiki
     
  13. MB460

    MB460 New
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    Thanks. I found a list on grbl last week that listed out which codes it uses and what they mean and saved that on my main desktop.

    But I think a problem that I am still having is..

    If I home it... it goes where it is supposed to.

    If I go to the drop down and say to go to machine home, it doesnt go to that spot. It goes wherever it wants to go. It's almost like the machine home isnt saving. The only cuts that I have successfully made are those that spiral down and enter into the stock before cutting a pocket. Any other cut has always plunged into material, dragged across the work piece, then raised, and started "cutting" 3mm above the work piece. Even when using the spoilboard itself as the work piece and trying to cut a straight line.

    This is my biggest issue.

    I got caught up doing other work so haven't checked the videos yet, but will shortly. Maybe these will address that.

    I'm using the openbuilds control software and m460 to make g code and windows 10. I have found videos over the last few weeks "do this do this this then go" and the random hipster guy in the video says "see? That easy!" And pulls up a cute little smiley face thing he made. Meanwhile my spindle gets torn off of the machine because it plunges and drags. (This actually happened once).

    I'll check the videos and see if they have an answer. Work day.. hard to not work lol.
     
  14. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    Ignore the hipsters. Watch our official YouTube Channel...

    Home sets Machine Coordinates
    SETZERO sets Work Coordinates. You might as well disable homing (keep switches as hard limits as a safety feature). Homing always confuse beginners as the mental image of machine vs work coordinates are hard to grasp. Ignore machine coordinates. Only work in G54 for a while till you build up skill. Just use Setzero buttons. Jog to the origin on the material (top surface of lower left corner for example), click setzero xyz, then run. If it runs wrong, your fusion work is wrong. Fusion is incredibly hard, not a good call for a beginner i would say
     
  15. MB460

    MB460 New
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    Machine home is where the zero of the machine is. When setting the work home, that tells the machine "ok you need to move this far xyz to get to the work surface and start the job. The part lives here in relation to your home" that's my general understanding of it. Upside down, backwards, inside out reverse or up down whatever, that doesn't confuse me. I'm ambidextrous and cardinal directions don't confuse me. Haha. What confuses me is why when I click the button, the machine bounces off of the limit switches and says "yay! This is home!" Then I say "ok machine, go home now" it says "where is home? Alaska? " and takes off running. When I home the work piece with the tool and I say "ok go to the work piece home" it says "ok... here it is" and goes there... then after a few times it says "well.... this is where home is now... I'm 5mm off of where you said it was, but it's close enough" and I say "NO! It needs to be exact." And i re-zero. Repeat process...

    But to reiterate what you're saying, using only g54, does it only work that way by disabling homing? The first few times I tried to cut on this machine i did not run a homing sequence, it buried the bit so fast I thought it was going to break the Z off of the machine... i seriously thought I broke the machine. 2 days after assembly. Then I learned that i was supposed to home it first. Then it got closer but doesnt cut where I tell it to So disabling home will tell the machine that the parameters I set for home are the only home?

    My other problem is. I tell the machine where the work piece is. This is 000... it runs, (drags the bit) then pops up, pops back down and cuts above the surface despite dragging the bit. It goes above and below home but never home.

    With that said.... I've gotten through one video and am still working in the meantime.

    How do I turn off homing? I haven't noticed an option in the software for that yet. Anything within grbl itself.... I'm completely at a loss. Not even sure how to open it, access it, or if it's even installed correctly, I just downloaded a link from another thread that said cause this to make it work with fusion. Couldn't even tell you which version is installed. But I do have a black box if that helps at all.

    As for fusion, I've been using it for modeling since it was beta, but the cam part is new to me, aside from watching videos a few years back but not having a machine to test things on when I made them. I currently design in solidworks, then import to fusion, then import the cam into openbuilds controller. There are 3 different places that things can get screwed up.

    If not fusion, what would you use to make a guitar? (I own a guitar business. I've been making them by hand. Demand requires me to start CNCing this stuff.)

    I'm not married to fusion... but when I looked at vcarve and the other one listed on the openbuilds site, one of them said that the max work area was too small for the 40x60 machine.

    If ditching fusion will solve my issues, I'll have it gone by the end of the day, as long as the alternative isnt too expensive. Or... free... and capable of 3d.

    I'll get back to you after I do what I keep saying I'm going to do and watch the other videos. Thanks again
     
  16. Alex Chambers

    Alex Chambers Master
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    Hi @MB460, may not be related to your problems, but what post processor are you using with Fusion?
    Alex.
     
  17. MB460

    MB460 New
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    Hi alex. Still learning terminology but attached is what I hope is an answer to what you asked .

    When I got the machine, i was having a lot of WCS issues (errors when processing the code), so another thread lead me to that one. No longer have those issues, but I do wonder if it's the right one for what I'm doing.
     

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  18. Alex Chambers

    Alex Chambers Master
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    I'm getting old - eyesight is going and struggling to read that on my phone, but it looks like one that works. :ROFL:
    I have a feeling that you have more than one issue, and I'm not an expert on OB control and blackbox - the others answering you are. It seems as though you might have to work through setting up your machine and your grbl settings and once they are right the fact that your wcs zero is wandering may mean you have a mechanical problem (or may need to set your stepper driver current)
    Sorry I can't be more helpful.
    Alex.
     
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  19. sharmstr

    sharmstr Veteran
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    Not true. I didnt read your complete post but see if this helps. Homing your machine is not the same as G53 being X0Y0Z0. For an explanation, refer to the "
    Why is Grbl in all negative coordinates after homing? Or it so annoying and not what I'm used to!" section of the grbl faq here: gnea/grbl

    GRBL machine coordinates are always negative. So, lets say you have your homing switches in the lower left of your machine. And lets also say that your X has a maximum travel of 1000mm. When you home, your spindle will be at G53 X-1000 (+ whatever you have set for pull off). When you use the dropdown to go to machine 0, its going to go to the upper right hand corner (in a positive direction to get to X0Y0) aka Alaska.
     
  20. MB460

    MB460 New
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    So as it turns out, I've seen 2 out of 3 of those videos. The hello world video was one of the first things I watched after assembling the machine. I have not attempted it, because I went straight into using fusion.

    Further updates.

    In the last few hours, I opened the control software, went to settings, and figured out that there was a list of things that popped up in the terminal. No one mentioned this to me.

    I scrolled through and found that $22 can toggle homing on or off. I toggled it off, zero'd the machine to an arbitrary point sans material to work from, so it would run the program in air. I loaded the program and hit go... the machine didn't move, the coordinates didnt change, literally nothing happened. I attempted to run it several times to no avail, so I toggled homing back on.

    I ran a homing cycle once again.

    Told the machine to go to machine home and it took off hauling butt across the table like mentioned several times previously. Nothing changed. FWIW, it went the opposite direction from the limit switches when i hit "go to machine home". Limit stitches are placed in the standard place according to the build videos. Home is towards me, and to my left if facing the spindle. It runs away the opposite direction and has from day 1. All wires are installed as per the build videos, they have been verified 10x over, and the motors all go the correct direction when jogging. Limit switches function correctly.

    Aside from going into the software and selecting which machine I have, I dont know of any pther setup that needs to be done in or out of grbl. Nor do I know how to access it currently.

    I went into grblb settings and cleared all coordinates, and completely reset the software and machine to factory, cleared the eeprom and jogged the machine. 1mm was more like 1.5 inches. I went through the setup, selected the machine in the software and saved settings, moved the machine, and 1mm became .97mm on the Y axis, verified by precision calipers. I didn't bother verifying X or Z. Wife came home with pizza, we ate, I fell asleep on the couch, woke up, took out the trash, pulled the roadster into the garage and started writing this.

    I appreciate the assistance so far, but I'm still not getting anywhere at the moment. The first comment was the most thorough and gave me great info, but I have nothing actionable as of yet. Anything that required research on my end, has been researched and some have given me a better understanding, at least well enough to use more correct terms to explain my issues, but many of these things are things which I have done already and have not rectified the situation(s). I am without a doubt clicking the zero button to set to work area zero, and a homing cycle should set home on the machine but doesnt. I usually home the machine FIRST, then zero the spindletobthebworkbarea. I am zeroing itbwas accurately as possible without having a probe or plate.

    What else is there?

    Using a less advanced software would only prolong my ability to do what I need to do and would lengthen my learning curve for ultimately using this software. I'm not having issues with the software itself aside from maybe not setting my retract and feed heights correctly and hitting the limit on thick stock, but that is usually an obvious issue which I tweak and re-gen the code.

    But these same issues appear even with thin stock. I tried to engrave a piece of 0.020 brass the other day and had the same issue. I broke 3 engraving bits from the machine trying to bury itself, and then cut 3mm above the work area (which as ive said is the case regardless of what I'm trying to run. It does this on every program I run. )

    Anyone else have ideas? I have seem similar threads to this and it seems that no one had an answer on those threads either. The OP's gave up on them before finding a resolution, or found one on their own and never posted the fix. What do I need to provide to this thread that would help find a resolution?

    I REALLY do appreciate the help and the time you guys are taking to answer. It's just aggravating, because it's been several weeks and close to 2 grand and i cant get this machine to do anything. I do have much more time to dedicate to this than a lot of people since I work from home. But I'm getting impatient and aggravated with this issue.

    Maybe I'll try the hello world tutorial tomorrow and see if it runs correctly. Since everything is pre-made, it should... right? And if it doesn't, then there's obviously something wrong.

    Could it be something with the black box itself?

    Thanks again
     
  21. MB460

    MB460 New
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    Sorry, thanks Sharm, you sent this as I was typing last diatribe. One second and I'll read. Thanks
     
  22. MB460

    MB460 New
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    Shram... ok that does make sense. And I did read that link earlier.

    So. There is work 0, machine 0 and g53 0. Home all takes into machine home, click go to g53, it foes to alaska, hit work home and it goes to the stock. Because essentially g53 is positive and machine home is negative. (Basically)

    So how do I set g53? Do I need to set g53? Do I ever need to use or assume that g53 is the same as either of the other two 0's?

    What is the purpose of having a machine home then g53'ing to the opposite corner?

    Given all of that, I've kind of assumed on my own that the discrepancy there, is what is causing my tool gouging and dragging issue hence why i want to be able to zero it out. But if it is butbthe same as the machine home, then that does not benefit me in the way I assumed it would.

    Thanks! :)
     
  23. David the swarfer

    David the swarfer OpenBuilds Team
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    seems to me you are getting a bit confused AND you have your home switches at bottom left which requires special GRBL setup.

    Gcode defines 7 basic coordinate systems (GRBL is a basic controller, fancy industrial machines have controllers with many coordinate systems)
    G53 - machine coordinates, where it homed, or where is turned on/reset if no homing. importantly, this code is not modal, it does not get remembered from one line to the next so every line that wants to use machin coordinates has to include G53.

    G54 to G59 - Work coordinates, where you have told it the work is. These are modal, you give it once and it gets remembered till it gets changed. Why are there 6 of them? So that you can have 6 mounting points (vices or jigs) and run the same gcode at the 6 different places, or for things like castings that are seldom the same size you can define some machining relative to the left side with G54 and relative to the right side with G55. Then after you have done the setup the code can set G54 and do the left side then set G55 and do the right side without further operator intervention.

    So, lets remove some things and get down to basics:

    please do this
    1 - go to the GRBL settings and turn off homing and turn off limits
    $22=0 ; homing off
    $21=0 ; hard limits off
    $20=0 ; soft limits off
    upload_2019-11-6_10-39-36.png


    2 - jog all axes to near the positive ends... workbee_1510-axis-directions.png

    3 - turn the controller off and unplug the usb cable.

    4 - by hand, move the tool (remember all axis directions are TOOL motion) to the positive ends of all axes, so TOOL moves X to right, Y back, Z up.

    5 - plug in the usb cable and turn on the controller and connect CONTROL. GRBL now considers 'here' as 'home', the 0,0,0 for the machine ( MCS).

    6 - jog to a workpiece (displayed coordinates can be anything, but you are jogging using Negative buttons, if not you have an axis reversed problem, fix that first and start again) and use the setzero buttons to set the work 0,0,0 (displayed coordinates are now 0,0,0)

    7 - activate the serial console and type in
    G21
    G0 X100 Y50
    and it should move the tool 100mm to the right and 50mm away from the X0Y0
    if it does not move 100mm and 50mm then you need to calibrate (under wizards and tools).
    if you calibrate, home will move, so jog to X+ Y+ Z+, switch off, manually home again, repower then start (6) again.

    8 - type
    G53 G0 Z-10 X-10 Y-10
    and it should move to the home position less 10mm.

    9 - click gotozero | work coord
    and it must return to where you set work X0,Y0 and Z0
    if it does not then we need to know exactly where it does go, and does it do the same every time you move away and move back like this? (with homing off that button will no longer offer an option to return to MCS but you can create a macro to do it)

    I believe that some of your issues are machine setup related, while others are fusion setup related, get the machine basics correct, then we can look at homing switches, and then we can look at Fusions clearance height and so on.

    and, do a thinner, simpler part as your first part (-: doing an ultra thick part with tricky clearance is just asking for trouble. the openbuilds hello world in some half inch foam is a good place because we know exactly what it is going to do. work 0,0,0 is the near left corner, and Z zero is the top of the foam.
     
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  24. MB460

    MB460 New
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    Thanks so much for the thorough and well written instructions.

    I won't go point by point, but, I did follow everything to the T. I made a small model in fusion and cut it successfully. Pic included.

    It is fractions of an inch "off" but nothing huge. It may come down to tool measurement and a slight mismeasurement when calibrating. I'm trying to find a way to use calipers to do this measurement without drawing lines, since lines are somewhat inaccurate.

    Anyway, I can't say for sure that this fixed the problem, but the first cut attempt looks very promising. There was no tool drag and this has been my most successful cut yet. So for that, I thank you.

    One question I have, is that after changing these settings, it appears to have disabled the limit switches. As long as I am careful, this is not a huge deal but I like having them for piece of mind even though they are on the wrong side.

    I'm going to play with this for a while, cut some more things, test it thoroughly, and I will update soon! Once I do so, maybe we can reintroduce the limit switches in the right spots. When adding the limit switches, I followed the assembly video, which put them front left, presumably for easier tool changes.

    Thanks again! And thanks to everyone who took the time! I'll be back
     

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  25. sharmstr

    sharmstr Veteran
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    David's a genius when it comes to explaining coordinates/homing and such. Glad you made some progress.

    However, location of homing switches are a personal preference. I prefer to have them in the lower left for several reasons. First, that's where I stand when I start the job. Having a limit switch within reach is an easy way to stop the machine if I forget to set my work zero (happens a lot). Second, like you, I have a 1510. Since I stand near the lower left, most of my jobs, tool changes and checking the X gantry for square (If you are still running belts, you'll want to do this often), happens there. Having homing go all the way back takes too long. Third, instead of using the jog buttons, I send a lot of commands via serial. Its easier to send positive commands after homing than it is to send negative commands.

    There's no wrong location for homing. Just understand that G53 X0Y0 is your machine 0. If your x and y switches are in positive locations (upper right, $23 set to 00000000) then homing will set your machine 0 to your switch locations. If like me (and 1,000s others with OB machines) have your switches in the negative locations (lower left, $23 set to 00000011) then homing will calculate your machine 0 by using the values you have set in $130 and $131. i.e. If $130 is set to 990, machine 0 will be 990mm from your switch.

    While its important to understand all of that, the only time I ever use G53 is to retract Z at the end of a job. I never use it for X or Y moves. And I've never had a need to send the machine to Alaska :)
     
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  26. David the swarfer

    David the swarfer OpenBuilds Team
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    looking good!
    bits are seldom the size stated on the box, measure them then tell Fusion the exact size.
    also, when calibrating you must calibrate over the longest distance possible for the axis. I use a 500mm steel rule and an engraving V-bit and am very careful about parallax errors.

    Though the wizard in OpenbuildsCONTROL does all the math for you, you do need to know the proper process HOWTO Calibrate your CNC Machine for MACH3 or GRBL

    what we have 'fixed' is removing the homing switches from the mix. AND I think we have established where the setup WCS 0,0,0 are in Fusion and how that relates to setting up the machine.
    With limit switches off and homing off you cannot enable soft limits either.

    My machine has neither home nor limit switches. Up to me to engage brain and make sure my part is placed correctly (for big ones, small ones are seldom an issue) and that I have set zero properly. One part of doing this is clicking the 'check size' button which will traverse the tool around the outline of the part you have loaded. A very useful crosscheck, and let it crash now instead of while cutting <-:

    This is exactly the correct process, build knowledge with a known working system. We are climbing 2 mountains at the same time, 1 = operating the machine, 2 = operating Fusion360 to get code that suites the machine. Climbing the 'make homing work' at the same time is not the best idea.

    On the subject of positioning for tool changes, you don't normally do that at 'home'. On my machine this is far away against the wall! But this is what the gcode G28 is for. manually home as usual (technically, once you have done this and remember to park it there (that macro button I mentioned) before turning off, you don't really need to do anything but turn on) then
    1 - jog to where you want to change tools (Z HIGH, right?!)
    2 - go to the 'serial console'
    3 - enter G28.1 and press enter

    now GRBL has stored the current position and you can go there anytime by issuing a G28. Make a macro button for it (-:

    Using G28 hinges on always having home in the same place, whether you have home switches or do a manual home like I described does not matter, just so long as it is always the same as it was when you set up the G28 position. This is because GRBL stores offsets from the MCS for G28, so if the MCS changes so will the G28 position.
     
    sharmstr likes this.

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