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This topic contains 94 replies, has 12 voices, and was last updated by  kd2018 1 month, 3 weeks ago.

Viewing 30 posts - 61 through 90 (of 95 total)
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  • #95530

    Ryan
    Keymaster

    Yes pin 42 (I think) is pwm, and there are a few more that are not pwm free.

    #95540

    kd2018
    Participant

    Well I had a brain fart…

    This whole time I was thinking I only had access to the “Fan 2” header. Duh, I have Fan 0 and Fan 1 right above it! I suppose the combination of the header not being standard dupont pins and a picture I saw somewhere that crossed all those out as not used in mpcnc I had just dismissed them. My mistake.

    #95548

    kd2018
    Participant

    Limit switches are only active during homing.

    Can/should we enable the limit switches with M120?

    http://marlinfw.org/docs/gcode/M120.html

    #95569

    Barry
    Participant

    Ehhhhhh.  I touch the switches sometimes with a few of my projects.  Really, you shouldn’t have to worry about it, you know the size of your cutting area, you shouldn’t be designing anything bigger than that anyway.

    #95574

    Jeffeb3
    Participant

    and keep in mind that closing and opening a serial connection resets an arduino.

    I think that’s actually a function of the software that connects. I think octoprint sends a reset command on connect, for example.

    #95576

    Jeffeb3
    Participant

    Yes pin 42 (I think) is pwm, and there are a few more that are not pwm free.

    You don’t want to PWM a mech relay. Even the pins without PWM would work.

    If you’re using the fan pins, make sure you don’t set it to anything but 255 or 0.

    Also, you’re toggling an inductive load, so I would be ready for the cheap relay to fail. It will either stick closed or stay open. You will always be with your machine anyway, but just be aware of that potential failure.

    #95586

    kd2018
    Participant

    and keep in mind that closing and opening a serial connection resets an arduino.

    I think that’s actually a function of the software that connects. I think octoprint sends a reset command on connect, for example.

    It’s a bit of both is my understanding. On the software side when opening serial comms, regardless of it’s arduino or not, it’s standard protocol to signal the DTR line. Some arduinos (and it looks like the RAMBo) use this signal as an opportunity to reset the board which is useful for development and rerunning the bootloader for uploading sketches. You should notice your board reset any time you reestablish serial comms with most serial terminals.

    #95589

    kd2018
    Participant

    Ehhhhhh. I touch the switches sometimes with a few of my projects. Really, you shouldn’t have to worry about it, you know the size of your cutting area, you shouldn’t be designing anything bigger than that anyway.

    I can’t help but think ‘what about Murhpy’s Law?’ But I hear you.

    #95594

    kd2018
    Participant

    Yes pin 42 (I think) is pwm, and there are a few more that are not pwm free.

    You don’t want to PWM a mech relay. Even the pins without PWM would work.

    If you’re using the fan pins, make sure you don’t set it to anything but 255 or 0.

    Also, you’re toggling an inductive load, so I would be ready for the cheap relay to fail. It will either stick closed or stay open. You will always be with your machine anyway, but just be aware of that potential failure.

    In the interest of keeping Murhpy at bay it might be advisable to tweak the following code in Configuration_adv.h

    /**
    * PWM Fan Scaling
    *
    * Define the min/max speeds for PWM fans (as set with M106).
    *
    * With these options the M106 0-255 value range is scaled to a subset
    * to ensure that the fan has enough power to spin, or to run lower
    * current fans with higher current. (e.g., 5V/12V fans with 12V/24V)
    * Value 0 always turns off the fan.
    *
    * Define one or both of these to override the default 0-255 range.
    */
    //#define FAN_MIN_PWM 50
    //#define FAN_MAX_PWM 128

    #95612

    kd2018
    Participant

    Okay, I’ve had a little time to get my head around the RAMBo schematic and pins_RAMBO.h.

    I see pin 45 is defined as SPINDLE_LASER_PWM_PIN and broken out to the motor extension MX2 header through a voltage divider. Can we readily use M03/M04/M05 through firmware as is without any changes? Are folks already doing this w/ their mpcnc? I’d rather use M03/M05 for the router than M106/M107 for the sake of clarity.

    Can anyone tell me off hand what the voltage is at that header?

    I only ask because I’m not in front of the machine right now but I could go ahead and place an order for an appropriate relay if I needed to.

    #95616

    Barry
    Participant

    The worst that happens when you hit the hard stops is it stops going in that direction and the steppers just skip.  Sure it ruins whatever you were cutting, but that would have happened anyway.

    #95644

    Jeffeb3
    Participant

    In the interest of keeping Murhpy at bay it might be advisable to tweak the following code in Configuration_adv.h

    I wouldn’t mess with that. You’re just as likely to accidentally scale a 255 to 250 with those…

    Can anyone tell me off hand what the voltage is at that header?

    That looks to me like it’s coming right off the arduino. If so, then it’s a 5V output.

    #95645

    Jeffeb3
    Participant

    If you look at this schematic, right in the middle is the fan0 (in the MOSFET section):
    https://www.reprap.org/mediawiki/images/7/75/Rambo1-1-schematic.png

    The FAN-0 label comes from the atmega 2560, and goes through that little transistor logic to switch pin 1 of jumper “X36” between 0V and 12V. That’s the kind of circuit that would mean you would need a 12V relay.

    #95650

    kd2018
    Participant

    In the interest of keeping Murhpy at bay it might be advisable to tweak the following code in Configuration_adv.h

    I wouldn’t mess with that. You’re just as likely to accidentally scale a 255 to 250 with those…

    I don’t follow. But I’ll admit I have already changed them both to 255, now the fan pins simply function as digital on off pins no matter what S### I send it.

    #95651

    kd2018
    Participant

    If you look at this schematic, right in the middle is the fan0 (in the MOSFET section):

    https://www.reprap.org/mediawiki/images/7/75/Rambo1-1-schematic.png

    The FAN-0 label comes from the atmega 2560, and goes through that little transistor logic to switch pin 1 of jumper “X36” between 0V and 12V. That’s the kind of circuit that would mean you would need a 12V relay.

    Agreed. But I gotta admit now I’m a little confused as to what you’re responding to. That is an older schematic you’ve linked there. Here is the schematic for the 1.4 board. https://github.com/ultimachine/RAMBo-1.4/blob/1.4/Project%20Outputs/Schematic%20Prints_RAMBo_1.4a.PDF

    You’ll notice that motor extensions on page 2 of the pdf, the pins go through a voltage divider presumably stepping the voltage down. This is what I was referring to. But no matter, I was able to get back to the machine and measure the voltage on those pins a just a little bit ago and you were right too, it’s still 5v.

    That said, I have since tried the M03/04/05 command and have been unable to get it to work as expected so I’m going to stick with the 12v fan pins for now. (I did enable them in the config, still didn’t work)

     

    1 user thanked author for this post.
    #95838

    kd2018
    Participant

    Now I’m starting to get somewhere

    1 user thanked author for this post.
    #97374

    GaryW
    Participant

    Looking to do the same here. I bought this https://www.amazon.com/gp/product/B07DSZFLMQ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

    and I have it installed it in my control panel. I powered it with the 5 volt aux. power which I believe is fine based on this being optocoupled isolation and consuming 190mA  MPCNC-Control-Panel-
    You can see the relay in the bottom right of the control panel. It is showing active because I jumped the 5vdc leg to the signal leg and configured it for switching HIGH. I am looking for a pin and some code so the Dewalt spindle starts before moving and stops after completion.

    I would be grateful if anyone has some ideas on this.

    1 user thanked author for this post.
    #97378

    kd2018
    Participant

    Maybe you could take a crack at getting pin 45 and M03/04/05 to work. Maybe someone knows how to get it working?

    I tried enabling it in the firmware in configuration_adv.h at #define SPINDLE_LASER_ENABLE and my multimeter then showed 5v at pin 45 but gcode wouldn’t switch it. But I have moved it down in the list of priorities for now.

    As far as getting it to start and stop when you want should be pretty easy. If you’re using Estlcam if you go to Setup -> CNC Programs -> Texts -> Program start / Program end you’ll see where you can modify “header and footer” gcode to whatever you want. Estlcam already has code here to start and stop a spindle. In my case I’ll change these to start and stop the “fan”.

    What enclosure are you using? How hot is it getting in there? Is that an aluminum mounting plate under there? I was looking at some ABS NEMA electrical boxes about that size but wasn’t sure what kind of heat I’d be generating between the power supply + RAMBo + rpi + SSR. (I’ve got a few 5v ssr’s laying around)

     

    For reference:

    https://github.com/ultimachine/RAMBo-1.4/blob/1.4/Project%20Outputs/Designators_RAMBo_1.4a.PDF

    https://github.com/ultimachine/RAMBo-1.4/blob/1.4/Project%20Outputs/Schematic%20Prints_RAMBo_1.4a.PDF

    #97822

    kd2018
    Participant

    So I dropped the middle assembly and cracked a xyz part and had to print a new one. When I took it apart I noticed that the infamous 1.25″ outer bolt on the xyz part digs into the xy part. Is this by design?

    No matter what I tried I could never get the middle assembly square via the tension bolts, tightening any of them always pulled it more out of square. Could these bolts be the source of my heart burn? Any objections to me using washers on the bearing side to take up some of the extra length?

    I imagine just flipping the bolt around would interfere with the z axis mounts?

    #97833

    Ryan
    Keymaster

    Hmmm, no it is not intentional. I will take a look at mine to see how close they are. I could see if yours were a bit too loose the pressure would force them into it a bit but that is just speculation and I doubt it is the case. First I have seen of this but I am going to look into it.

    But that light of pressure would actually be a good thing and make your Z axis more rigid.

    #97836

    kd2018
    Participant

    Referring to the attached image my problem is theta is (slightly) greater than 90, tightening any of the tension bolts does make it more rigid but makes theta even greater. With it slightly looser I’d relied on the rollers and dual endstop firmware to torque it back to square.

    When I can get back to the machine tomorrow I’ll try to effectively shorten those bolts to see if it makes any difference.

    #97870

    kd2018
    Participant

    According to my caliper those bolts turned out to be 1.29″. I ground them down to just under 1.25″ and now they don’t touch or interfere.

    And after some brief fenangeling the middle assembly finally came together snug and square for the first time. I can’t say definitively that was the source of my problem as I tweaked two other bearings, but you can take it as another data point.

    1 user thanked author for this post.
    #98872

    kd2018
    Participant

    According to the perpendicularity tester for the dw660 my tool is leaning off the front of the tool mount a bit. I can say with high confidence that the table is flat and the zaxis itself is perpendicular. What’s the preferred method of shimming the dw660 mount into proper alignment?

    #98903

    Ryan
    Keymaster

    If you can’t just move the mounts around a little bit I have used tape or paper.

    #98909

    kd2018
    Participant

    This seems like a dumb question but what do you mean move them around a little bit? It’s all locked down pretty tight.

     

    As for shimming, shim between the tool and tool holder, or between the mount plate and tool holder, or don’t care?

     

    For the record I’m showing a difference of I’m guessing around 1/16 to 1/8 inch of a gap from the screw to the bed at the end of the perp tester.

    #98940

    kd2018
    Participant

    Here’s the enclosure plan:

    2’x3′ MPCNC up top, CR-10 Mini on bottom. There is a 1.5″ wide trough along the 3 interior sides of the cutting bed for the motor cables to ride. The 2 panels on the sides of the mpcnc will slide up and down so that I can slide long material through.

    Hopefully the 3d printer cabinet will be buttoned up enough to keep the dust out. I’ll seal up the edges and rig up weather stripping of sorts at the door. The mpcnc doors sit proud of the front of the cabinet but the printer’s door will be recessed in the frame to minimize surface for dust to settle on.

    Suggestions?

    #98952

    Ryan
    Keymaster

    If you can not loosen and move them a bit, shim between the tool and mount.

    #100082

    kd2018
    Participant

    Finally got around to making some simple test cuts. 4″ circle, 4″ square.

    I missed the mark but I think it’ll do for now

    1 user thanked author for this post.
    #100115

    kd2018
    Participant

    And we’re off and running!

    1 user thanked author for this post.
    #100377

    kd2018
    Participant

    2nd cut done. Must have taken over an hour and a half… Actually started this yesterday and had to stop part way though and continue today. I was worried I’d have issues restarting but the dual end stops did their job as far as I can tell.

    Ryan, whats  the tolerance on the lowrider flat parts?

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