Calibration problems


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    This is a person who has been through the loop..you can probably trust what they say!

    I got the arcdroid all setup, did the calibration, it was out by about .7mm on the x and .2-.3mm on the y. Good enough. However checking the points on the calibration triangle and drawing a line, they were at a right angle but a little askew from the axis on the screen. I did some test cuts, then a couple circles and they were ovals. So I decided to recalibrate, thinking maybe I had thrown something off. I cannot get anywhere near an accurate calibraition. I went through the proceedure at least a dozen times or more and not only does the stylus appear off screen sometimes after homing but now if i check the points on the calibration triangle for the 313mm measure, it's somewhere between 20 and 50mm off in the x and between 3 and 20mm off in the Y after each calibration. And now drawing a line, it's really askew from the grid, as one would expect with it being off so much.

    I tried to download the firmware off the website to see if a reload would help it but apparently the download link only opens a new windws to the site. (I know reloading firmware has fixed 3D printer problems for me in the past.) Maybe there is a hard reset function hidden somewhere?

    Anyone else have any problems with the calibration?



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    This is a person who has been through the loop..you can probably trust what they say!

    Update: I wanted to try a few things to see if I could narrow down where the issue is, now I can't even complete the calibration routine. At different points I'll hit the 'Next' button and it will just go back to the menu screen. And the last calibration I had done, readings for the 2 rail were in the 38 range.
    I have an email in to Andrew, hopefully a firmware reload will sort it out. 


  • Hi Jason

    Responded to your emails!  We'll get you sorted.


    Cheers

    AM


  • Well, after a bunch of tries, I finally got the unit calibrated.  Was having problems with the switch not reading the holes, sometimes it would miss one or more during the calibration run.  The solution was I 3D printed a housing to go over the switch which raised the bottom of the plastic switch holder about 3mm above the rail, thus the switch housing was no longer resting on the rail during calibration.  This allowed for free switch lever movement and the program to read every hole when moved during calibration.  


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    This is a person who has been through the loop..you can probably trust what they say!

    @Harry WHITEHEAD  Interesting. I got it to work a few times but with no regularity and calibration was always off. After speaking with Andrew today, there is a leeway built into the values it will capture while calibrating, if the measurments are outside of these values, they won't capture even though you can see the switch being triggered or if they are too extreme you'll get too large a margin of error. His suggestions was to space the triangle a 1/4 inch up in the Y direction. I did this along with a full reset, G28k before and after. Worked perfectly the first time and was super easy. I'm within 0.45mm on Y and 0.15mm on X. 
    A few people are having this issue so there may be a firmware update coming soon. 


  • Sadly the spacing didnt work for me. I have tried lots of various spacing and continue to miss almost all holes on the #2 rail. :(

    I have factory reset multiple times and have grown weary. :(


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    This is a person who has been through the loop..you can probably trust what they say!

    @William Adams I'm working through editing a follow up video now.

    I had more issues and some buggy things. The final conclusion, the set screws on smaller drive pullies on the stepper motors need to be super tight. Because there's no flat spot on the motor shafts and because of the gearing with the belts, just snug isn't enough on those screws. They really need to be as tight as you can possibly make them, just using an allen key, you'll round out the head before you get them tight enough. You really need a good fitting hex driver bit. Or cut an allen key off square with no bevel and use a lever with it if need be. Don't try to use the ball end.

    This completely solved the issues I was having. I've been through every other troubleshooting point and this is most important before anything else. Just a little bit of slippage will screw up homing, from there it's impossible to get through cailibration, or if you do, have the machine apply it properly. Because next startup when you hit home, it will be off again. The slippage seems to happen when the big arm locks into it's home position to home the other arm. Not saying this is your issue but, it is the thing you need to ensure before moving on to anything else. 
    Hope that helps. 


  • @Jason Burns 

    Yep this is exactly what we have found.  The approved Pilot run units were assembled by engineering and their concept of "Tight" seems to be much better than the general factory.  So Production units vary a bit too much.

    We've made a running change for much better set screws and flat spot on the shaft is coming.

    When in doubt, Loctite is your friend!


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    This is a person who has been through the loop..you can probably trust what they say!

    @William Adams Also just realized, this is a different thread. Go look for my "trobleshoot video" thread, see if any of that explaination helps. The follow up will be posted in that thread when I get it done, hopefully in the next day or two.


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    This is a person who has been through the loop..you can probably trust what they say!

    @ANDREW Miller hahaha....that's exactly what I did. Little dab of locktite!


  • I would also like to add:

    Do NOT lift the unit by the arms. I'm figuring out how to install handles on the base with countersunk screws, balanced, for just that reason.

    Taking mine out of the snug fitting packing I thought "Boy, guys are going to lift by the arms and knock everything haywire."

    Carry on...


  • @KWICK Aronson 

    Best way to get it out of the box is to yank up on the plastic baggy

    Sorry its' so snug but, better that  than arrive all busted.  😄

     

     


  • I new here and just got my arcdroid very excited lol. Im doing the calibration and the numbers im getting on the first shuttle run very the high of 20.26 and low 19.55 how do I fix this issue 



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    This is a person who has been through the loop..you can probably trust what they say!

    I think that's about right. I think all are around 20, + or - a bit. As long as it's registering each hole, you're fine.

    If it's not registering all holes, try going into the command and enter G28K. Machine will home and lock the arms. Back out of command, arms should unlock, then do calibration. 


  • @ANDREW Miller Production units vary.  I hope you reach a point where you folks take delivery and do QA in-house.  Grizzly does that, I've heard.  It would be worth the extra bucks for me to recieve a fully functional unit right from the get-go.


  • @Donald Smith @JT Simmons These numbers are perfectly  fine they do not need to be exactly 20mm the machine uses a complex algorithm to calculate relative position of holes not absolute position.  Readings that show up on the screen during calibration are aproximations and don't actually reflect the end result of the calibration


    Cheers

    AM


  • @ANDREW Miller I'm not saying anything about the precision, that seems to be really good, but rather about the mechanical issues some of the Arcdroid units have.  The main thing seems to be loose pulleys.  Personally, I'm over the moon that you decided to develope this machine and offer it at an affordable price.  I would be hard put to justify a purchase of eight or ten grand on something I won't be using constantly, not to mention the shop space a machine like that would occupy.  Keep it up, I'm rooting for your success.


  • @Jason Burns  I am haveing calibration problems I tried doing update off the website . all i get is a error reading from the SD caed reader. iv tryed 3 different cards but no luck .


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    This is a person who has been through the loop..you can probably trust what they say!

    @Ronald Mathis what size cards? And you unzipped the file before putting it on the card?


    The most reliable way I found to do a calibration is to go to command, type G28k. It will home and lock the arms. Then hit back until the main menu. Arms should unlock. Now do the calibration routine. Then I usually do a power cycle. After sorting out my pully issues, using this method I get a good calibration every time. If you check using the 313mm measurment with the triangle, be sure to switch back to the stylus and plug it in. Otherwise things may be a bit off if you try to measure with the torch. 


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