New Build in Frisco TX

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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 - 31 through 60 (of 95 total)
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  • #79472

    Jeffeb3
    Participant

    I don’t have the number, but when I made my MPCNC, I printed the foot only up to 5mm or so and it gave me a nice drilling template.

    1 user thanked author for this post.
    #79513

    kd2018
    Participant

    Thank you for the suggestion Jeff but after some digging I figured out how to pull dimensions.

    I was thinking it would be easier for me to layout my legs square if I could center punch where everything goes referenced off the conduit centers and 3-4-5 triangles, so I made a 1:1 template. I’ve attached it here in case anyone else would find it useful.

    #79560

    kd2018
    Participant

    Like this!

    It’s going to be pretty embarrassing if this machine turns out crooked.

    #79564

    Ryan
    Keymaster

    This could be the first, square on the first try build…I am rooting for you!

    #79757

    kd2018
    Participant

    It’s starting to look like an mpcnc.

    The bottom bearings in the XY parts don’t ride on the conduit. Neither do the inner bearings of the xyz part, they spread as the z rails pushes the plastic apart such that the conduit can’t reach the inner bearings. Normal?

    #79759

    Ryan
    Keymaster

    Normal?

    No. Not at all.

    I would take apart the center and try again, very carefully following my instructions. It probably has to do with over tightening and the Z axis spacing.

    #79773

    kd2018
    Participant

    Didn’t think so, will do. But for the record all the tensioners are sloppy loose. The other bearings are just barely tight enough till no more slop in the bolt, then maybe backed off a hair. I figured I’d be tightening those bearings. I’ll play with it. This is just a ddry fit after all.

     

    #79776

    Ryan
    Keymaster

    I have a torque rating for non tension bolts.

    It is an interference fit, the bearings should all touch at all times. For them not to touch something is very far off.

    This is in the FAQ’s, most people solve this simply by rebuilding it.

    #79778

    kd2018
    Participant

    Do you mean the external link to the torque converter that says 5.5 N.m?

    #79784

    Ryan
    Keymaster

    Yes, that is for all 1.25″ bolts, the rest should be as stated in the instructions. With zero tension on the tension bolts all bearings should touch, if they do not you have an issue. I could be many things at this point.

    #79798

    kd2018
    Participant

    I guess we have different ideas of snug. I busted out the torque wrench and tightened all the 1.25 bolts to 48 in*lb. It’s all much tighter. They roll kind off rough now…

    All the bearings ride on the conduit now except for one, a bearings at a tension bolt C.

    What’s interesting is without the z axis in place the x & y rail are perfectly perpendicular. When I slide in the z axis it’s so tight it pushes the x y rails way out of square.

    #79803

    Ryan
    Keymaster

    48 in*lb

    That does not sound right, I have to double check that.

     

    What’s interesting is without the z axis in place the x & y rail are perfectly perpendicular. When I slide in the z axis it’s so tight it pushes the x y rails way out of square.

    Yup and then some XYZ bolt adjustments and it should be square again. Took a few revisions to get it to where it worked well for everyone and there seems to be very little trouble getting it square now a days. Make sure to follow the instructions in order, it should have all 6 bars in place before any of the XYZ tension bolts come into play.

    #79804

    Ryan
    Keymaster

    That does not sound right, I have to double check that.

    All good.

    #79810

    kd2018
    Participant

    I can’t be sure but I think the z rails were slightly out of parallel… depending on which “flat” surface I chose to test it on. I’m rebuilding tomorrow because now I have to wait on glue to dry in the nut traps.

    Either way when I take a piece of spare conduit just by itself and run it down the xyz berings the xyz plastic is forced to bend out of the way. Just one peice is enough to throw off the square of the XY rails. But when I loosened all the xyz bearings enough that I could just wiggle the 1.25″ bolts then the bearings move out of the way for the z rail instead of bending the plastic. When the plastic doesn’t move then that back bearing engages. Should I try it loose like this or go ahead and tighten them back up and adjust elsewhere? (Bearing down on the c  tensioners I’m guessing)

    #79818

    Ryan
    Keymaster

    The 1.25″ should all be tight. The gantry should 100% flex open when the Z is inserted, by design. I am telling you the easiest way is just do it again, something is off, and the Z should be flat.

    There is no easy solution because something is wrong. Anyone that has the issue either just rebuilds it and it works or they use it for a bit then rebuild it. Worst case scenario your prints are bad from a odd printer calibration, best case a rebuild will fix it.

    #79820

    kd2018
    Participant

    You’re the boss, I’ll crank her back down.

    Unless you mean to reprint, I promise did take it apart and rebuild it. My 4yr old assistant and wrench inspector can attest to it! Just not right now, it’s past her bed time.

    1 user thanked author for this post.
    #95112

    kd2018
    Participant

    @Ryan,

    How did you wire the limit switches at the switch? Can you take pictures of the connection? Using the limit switches and connectors I have from your kit, the spade connector def wont fit on the mount.

    https://www.thingiverse.com/thing:2847042

     

    Also, do you still recommend the kastar power adapter? Mine lasted about 5 minutes of use before it broke… I’m way past return period too. Im debating on reordering the same model or not.

    #95114

    Ryan
    Keymaster

    Bend the tabs to make it fit.

     

    We haven’t had power supply issue in a while, I do like them.

    1 user thanked author for this post.
    #95126

    kd2018
    Participant

    Thanks for the quick response. Sorry though, I see where it’s been asked and answered several times on the tingiverse page.

    But another question (I did search this one before asking) : how did you fasten your limit switch to the roller plates? Looks like just a zip tie?

    My smallest zip tie is 2.45 mm, the holes on the limit switch are 2.3, I suppose I could just whittle on the zip tie to make it fit… I tried some twist ties but couldn’t get it tight enough for my liking.

    #95162

    Barry
    Participant

    I don’t know where he found those tiny zip ties, I used 2mm screws.  If you have a 2.5mm drill bit, there is enough plastic in there to inbiggen the holes a touch.

    #95203

    kd2018
    Participant

    Roger that. I’ll get after the holes with the inbiggenator.

     

    As a side note I made a last second decision to order a different power supply since the top reviews for the kastar aren’t exactly glowing. While I was at it I also picked up a relay to control the power to the router & vac.

     

    Speaking of which, per other threads I’m planing to use the fan header on the RAMBo 1.4 for the relay, is anyone aware of another header on the board I can easily use for a second relay? I’d like to control the router & vac separately, more specifically delay switching the vac off until a few moments after the router has been turned off… but I suppose if I had to I could just rig something up with a second mcu.

    #95427

    kd2018
    Participant

    It’s Alive!

    It’s made its first movements using a rpi3 with Jeffe’s v1pi image with cnc.js. I’ll need to clean up the wiring before I can start running tests.

     

    How are you guys implementing software limits? (RAMBo 1.4 board / MPCNC_Rambo_T8_16T_LCD_DualEndstop firmware)

    Re marlin’s docs I’ve found the software endstop section in the firmware, by default Ryan has the max limits disabled. Before I started jacking with this I wanted to get y’alls input. Also, are soft limits implemented by the gcode senders or any where else? Or are most people running without limits (beyond homing)?

     

    The config looks very straightforward anyway:

    // The size of the print bed
    #define X_BED_SIZE {MY X LEN HERE}
    #define Y_BED_SIZE {MY Y LEN HERE}

    #define Z_MAX_POS {MY Z LEN HERE}

    //Uncomment this line to enable max limits
    #define MAX_SOFTWARE_ENDSTOPS

    #95437

    Geoffrey
    Participant

    I don’t know where he found those tiny zip ties, I used 2mm screws. If you have a 2.5mm drill bit, there is enough plastic in there to inbiggen the holes a touch.

    I believe the proper spelling is “enbiggen”.  It’s a common grammatical error.

    1 user thanked author for this post.
    #95446

    Barry
    Participant

    I don’t know where he found those tiny zip ties, I used 2mm screws. If you have a 2.5mm drill bit, there is enough plastic in there to inbiggen the holes a touch.

    I believe the proper spelling is “enbiggen”. It’s a common grammatical error.

    I ain’t got no good English.

    #95448

    kd2018
    Participant

    Anyone have input on my 2nd relay pin and soft limit questions above?

    #95505

    Adam Rivard
    Participant

    Following along.  I too am curious about max end stops to avoid crashing the machine.

    #95509

    Barry
    Participant

    Limit switches are only active during homing.

    #95511

    Jeffeb3
    Participant

    Anyone have input on my 2nd relay pin and soft limit questions above?

    They should almost all drive a relay board like that. If those don’t work with a 5V input, these should:

    https://www.amazon.com/FICBOX-Channel-Optocoupler-Support-Trigger/dp/B07BS6PCR6/

    I guess they would both work, and you just need to power it with 5V to be triggered by 5V.

    #95522

    kd2018
    Participant

    Limit switches are only active during homing.

    @adam Rivard

    I went ahead and made these changes in the firmware: enabling max_software_endstop and then adjusting the “bed” size to my work area. I tested the soft limits with G1 commands, seems to work just fine. If anyone can think of an reason I shouldn’t have turned this on or if this isn’t very reliable please let me know!

    I’m guessing here because I’m new to cnc, but it seems to me that the way the soft limit works is you first half to home your machine after  you’ve powered it on so that the machine can get its own bearings. Only then can it implement the software endstop settings you’ve setup. Also you’ll need to re-home anytime the rambo (arduino) is reset and not just after powering it on, and keep in mind that closing and opening a serial connection resets an arduino.

    Please anyone correct me if I’m wrong or have anything to add.

    #95523

    kd2018
    Participant

    What I’m wondering is if anyone is aware of a 2nd header on the RAMBo 1.4 board that can readily be repurposed as a relay pin in the same way the Fan2 header can be? My intention is to control the router and shop-vac separately. The RAMBo schematic was giving me a headache so I thought I’d ask the you guys first.

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