Build Thread Saturn 2 4x4 w/ Nema34 closed-loop - In Canada - Page 3


Page 3 of 17 FirstFirst 12345613 ... LastLast
Results 25 to 36 of 200

Thread: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

  1. #25
    Registered
    Join Date
    May 2017
    Location
    Canada
    Posts
    76
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Quote Originally Posted by Ntl View Post
    That sucks hope it didn't break anything when you were running a program.
    Nope. Was running an "air cut" with the code. Learned my lesson on that once or twice on my smaller CNC. Was lucky before but the Saturn 2 with Nema 34s on it I imagine would be much less forgiving.

    Quote Originally Posted by bhurts View Post
    Could it be the cable causing the problem. If it happens sometimes and not others that could indicate a break or intermittent connection.

    Ben

    Sent from my E6810 using Tapatalk
    I thought of that, but that's where the encoders come into play. If the motor did anything that the driver didn't tell it to do, it would alarm and fault out. I'm using closed loop steppers and drivers.



  2. #26
    Registered
    Join Date
    May 2017
    Location
    Canada
    Posts
    76
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Hey there everybody... so I've finally had a bit more time to dedicate to my machine the past couple days. After a whole bunch of troubleshooting, I did narrow down the previous issue to a faulty driver. I contacted the seller and after a couple weeks, I swapped out the faulty one with a replacement. No more issues on that front. Since then I've been able to cut all the holes in my wasteboard and spoilboard and it turned out pretty good. This brings new to a new issue that I just can't seem to wrap my head around. I know a possible cause but I really hope I'm wrong. After the baseboard and wasteboard was finished and fastened, I thought I'd move on to calibration. Steps per inch went fine on the x axis. I think I was at 2036 instead of the starting point of 2038; fine that way. Then the Y axis. One would assume that it would be 2036 as well but I thought I would check it just to be sure, but it was out. It seemed closer at 2038, which I thought was odd but entered the value. This got me curious. I move the X axis almost all the way to the right and measured the travel on the A (slave) axis. It was not the same. Very odd. Something I also noticed is that when down on the homing end (front) of the machine, when I home and then hit the E-stop to cut power to the drivers, it stays right where I left it. However if I home, travel about 40 or so inches up the Y axis and then hit the E-stop, the gantry seems to spring back about an 1/8th" or so, removing the tension on the R&P gear as I can see it pull back up and into the rack. I think that this is the same issue from back in post #5, however it just "APPEARED" to go away when I tightened the R&P spring. Seeing that the gantry travelled smooth without the R&P being engaged since day one, there was something so obvious that I never thought to check. I measured the distance between the Y and A rails at either end. They're out by just over a 1/16th of an inch. Entirely not what I was expecting given that this machine was advertised as within 0.1mm.

    So my fellow CNC Zone members, what does this all mean? I'm a bit frustrated and therefore can't wrap my head around the geometry at this point to find a cause and then a solution. I should mention that I've also swapped the X and Y racks, thinking that it might be a difference in the manufacturing of the rack. Same result.

    I haven't reached out to Nate at this point as I'm looking for ideas to troubleshoot before going down that road.



  3. #27
    Member Ntl's Avatar
    Join Date
    Aug 2018
    Posts
    378
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    It's not going to matter if one side is a inch longer or a 16th of a inch. The only thing that could cause a problem is if the gear rack is off and even then you just need to square up the gantry. Don't go off the hard stops since they aren't perfect. What I did was use my laser and lined it up with the linear rail on one side marked the machine on both sides, then went to the mark on the other side of the machine and verified that the marks were in the same place. Doing this gave me a real reference point to square the gantry off of you can't square it up off any table measurements since the steel fabrication that was done on these is anything but precision unfortunately. Granted I have a high end very accurate PLS laser it has a accuracy of +-0.004 per foot. Get a good 4 or 5 foot t square if you don't have a good laser since it will be even more accurate and mark the rails then see if it is square. You may need to loosen up the gantry if the teeth aren't meshing properly. Let us know what happens.

    Dan

    Attached Thumbnails Attached Thumbnails Saturn 2 4x4 w/ Nema34 closed-loop - In Canada-20190120_174910-jpg  
    Last edited by Ntl; 01-20-2019 at 08:54 PM.


  4. #28
    Registered
    Join Date
    May 2017
    Location
    Canada
    Posts
    76
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Quote Originally Posted by Ntl View Post
    It's not going to matter if one side is a inch longer or a 16th of a inch.

    Dan
    Hey Dan. Thanks for the reply. I think I might've not explained the 1/16th of an inch properly. It's not in the length of each the Y and A (slave) rail, but rather the distance between the two rails from one end to the other. They are not perfectly parallel.

    Leon



  5. #29
    Member
    Join Date
    Apr 2016
    Location
    United States
    Posts
    377
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Quote Originally Posted by wackocrash5150 View Post
    I measured the distance between the Y and A rails at either end. They're out by just over a 1/16th of an inch. Entirely not what I was expecting given that this machine was advertised as within 0.1mm.

    So my fellow CNC Zone members, what does this all mean? I'm a bit frustrated and therefore can't wrap my head around the geometry at this point to find a cause and then a solution. I should mention that I've also swapped the X and Y racks, thinking that it might be a difference in the manufacturing of the rack. Same result.

    I haven't reached out to Nate at this point as I'm looking for ideas to troubleshoot before going down that road.
    It appears your issue is the same as one I had on the machine I sent back. Yours just isn't as bad as mine was. When I measured the difference front as compared to the back of the right and left linear rails, it was .086" out. When I measured the frame tubes, the difference was .026" - significantly less. Here is a link to my build thread: https://www.cnczone.com/forums/finel...c-posts-3.html

    To put just over 1/16" (.0625+) into perspective, the maximum allowable deviation from parallel for linear rails is somewhere between .001" and .0017", depending upon the source. The max for Hiwin is .001. So, you are way outside the range. Your discrepancy is going to throw pretty much everything off. As ger21 put in my thread, "If the machine can't flex enough to accommodate the misalignment, the bearings will wear faster, or be damaged. Or they'll just bind and not slide at all." I'm betting that the "spring back" you're experiencing is related to the extreme lack of parallelism. Here's a link to the part of my thread where the subject was discussed: https://www.cnczone.com/forums/finel...c-posts-5.html.

    My Saturn 2 had so many problems, I finally stopped measuring and Nate took it back. However, if you have a long precision straight edge, you might want to run it along the bases of the rails and look for gaps. It could be that the holes for the linear rails weren't drilled in a perfectly straight line. You already know that the rails are not parallel, but for diagnostic purposes you might want to see of they are bolted down in a straight line. Maybe yes, maybe no. If they aren't, you have yet another layer of of problems. You may also find that the distance between the tubes is different (out of spec). It could matter, because the tubes are dished in the center (like most steel tubing). If the rails were mounted parallel on out-of-parallel tubes, there well still be a disrelation - one rail could be flat in the center of the tube on one side, while the other rail is angled slightly on the other side (it ride on the side of the dish shape). Think about checking the steel frame tubes to see if they were welded square, plum. There is a reasonable probability they weren't.

    Keep in mind that one problem often leads to one or more others, and errors can become cumulative (depending upon the nature and cause).

    I suggest you may want to read more of my thread that just the links I posted. Maybe it will give you some ideas.

    As the end of the day, I concluded that trying to fix my machine wasn't for me. The problems were more than what is contemplated in satisfaction guarantee. What I was sent was defective when built and far from the tolerances promised in the advertising. To Nate's credit, he gave me no hassles and did the right thing. I'm sure that my taking the time to photo document the issues made it easier for both of us.

    Gary


    Last edited by GME; 01-21-2019 at 02:02 AM.


  6. #30
    Member Ntl's Avatar
    Join Date
    Aug 2018
    Posts
    378
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Oh so you mean the span over x axis, I thought you were talking about the y axis. Dumb question but you're measuring in between the rails that the bearings ride on and not the steel tube that they bolt to right?

    If so I would pop out the plastic bolt covers the easiest way is to use a screw and a drill and just screw it in the middle of the plastic plug and they pop right out and then have Nate send you new ones. Then drop the motors and loosen all the bolts move the gantry to one side and tighten the bolts as you move the gantry to the other side the gantry will line up the rails if there's enough clearance in the holes of the linear rails with the bolts. If there's not enough clearance you could always either use helicoils and smaller bolts in the area that is off or you could bore out the holes. I'm not sure if any of this makes any sense? If not let me know and I can try to explain it better.

    Dan

    Attached Thumbnails Attached Thumbnails Saturn 2 4x4 w/ Nema34 closed-loop - In Canada-20190120_174910-jpg  


  7. #31
    Member
    Join Date
    Apr 2016
    Location
    United States
    Posts
    377
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Quote Originally Posted by Ntl View Post
    If so I would pop out the plastic bolt covers the easiest way is to use a screw and a drill and just screw it in the middle of the plastic plug and they pop right out and then have Nate send you new ones. Then drop the motors and loosen all the bolts move the gantry to one side and tighten the bolts as you move the gantry to the other side the gantry will line up the rails if there's enough clearance in the holes of the linear rails with the bolts. If there's not enough clearance you could always either use helicoils and smaller bolts in the area that is off or you could bore out the holes. I'm not sure if any of this makes any sense? If not let me know and I can try to explain it better.

    Dan

    Loosening both linear rails and trying to use the gantry to get them straight probably won't work. The technique assumes linear rails are perfectly straight. Often, the are not.. That's one reason why it's recommended that an edge be milled at the mounting site. The rail is then referenced off the edge and any irregularities can be worked out as you work down the length. Here's a link to the Hiwin PDF that covers all manner of info. Mounting starts on page 14. http://www.file-vault.us/pdfs/hiwinguideway.pdf. There are various options listed, but none of them involve loosening all of the fasteners and using the gantry to line up both sides simultaneously. What they all have in common is using precise techniques for alignment. For my newest machine, I will be using precision straight edges (.0002 in 12") for alignment. Not the preferred method, I don't have the option of milled edges.

    I've never seen helicoils used where there would be so little thread engagement. The walls of the frame tubing aren't all that thick. I'll defer to you, if you've successfully used them in tubing of this sort. However, there is another issue worth considering. 30mm rails use an M8 cap screw. The head is typically about 13mm. The screw hole size is 9mm, so there is 2mm head contact area all around. The next size down is M6. The head on an M6 is 10mm, so the head contact area would only be .5mm all round (25%). For my taste, .5mm is way too little. Also, note that in terms of adjustability, there is only .5mm (.0197") of adjustment on a centered cap screw. Not nearly enough to correct a 1/16" (.0625) misalignment. Leon has more than 1/16", although how much more is unclear. Specs on rail parallelism allow for a deviation of .001 to .0017, depending upon the source. My Saturn was worse. I couldn't find a reasonable way to correct it.

    I have no idea what Leon plans to do, but he didn't get what he bargained for. If he takes the time to take measurements of other areas, he might find other things out of spec. My frame was welded out of square/plumb. I cannot help but wonder whether something like that is contributing to his issues. Anyway, I've been there. I sent mine back.

    Gary




  8. #32
    Member
    Join Date
    Sep 2005
    Location
    United States
    Posts
    1098
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    As I pointed out before the design of the Saturn 2 does not allow for the parallel re-alignment of the linear rails as its shipped. The CNCRP design appears to be fully adjustable. But if you had the linear rails of the S2 mounted on a 3/8 plate with slotted holes cut for parallel alignment and that rail plate could also be shimmed up and down if needed that I believe would work.

    Gary says the linear rails are referenced off the frame rail, I do not think that's true. I think the frame rail is just a mounting surface.

    My machine is fine but it all depends on how close the frame can be welded to true, and the placement of the rails when mounting.

    Retired Master Electrician, HVAC/R Commercial. FLA Saturn 2 4x4 CNC Router


  9. #33
    Registered
    Join Date
    May 2017
    Location
    Canada
    Posts
    76
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    So, just for the sake of trying to wrap my head around it, am I to understand that the rails being out of parallel from approximately 1/16th to 3/32nd of an inch over the length is indeed enough to cause the racking that I'm experiencing?

    Humor me and let me speak hypothetical here on a solution. So the lack of any adjustability if it's not set up perfectly upon assembly would seem to be a design flaw. Here's the what-if:

    ASSUMING that it was just and only a matter of the rails being out of parallel due to human error when drilling and tapping the holes for them, what if it were possible to make a hole in each end of each rail support tubing, allowing a bar to be inserted within the square tubing. This bar would be roughly the same length and width of the rail itself and would have threaded holes that precisely match the holes of the rail. The threaded holes currently in the square tubing could be then drilled a bit oversized to accommodate adjustability. The screws would go into the rail, through the tubing and thread into the inserted bar below, essentially sandwiching the square tubing Make any sense? Again, assuming that it was ONLY misalignment of the rails.

    Last edited by wackocrash5150; 01-21-2019 at 11:21 AM.


  10. #34
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    Shelby Township
    Posts
    33255
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Yes, that would work.

    It's not a design flaw, as there's no easy way to provide adjustability. It's a manufacturing defect.

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


  11. #35
    Member
    Join Date
    Sep 2005
    Location
    United States
    Posts
    1098
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Sure that would work and not effect the height of the Z like my idea would. You could lift the gantry high enough to unmount the rails one side at a time or maybe just slide them out as is. Then drill and tap those holes needed in the new flat steel bar. Drill out and elongate (if needed) the old mounting holes. In fact you might only need to do one side. Nether one of my 3" square tubing mounting rails have caps anyway.

    If you were 100% sure that in the future you will never move those linear rails, you and drill a hole and put ether a roll pin or tapered pin to hold any movement.

    Retired Master Electrician, HVAC/R Commercial. FLA Saturn 2 4x4 CNC Router


  12. #36
    Registered
    Join Date
    May 2017
    Location
    Canada
    Posts
    76
    Downloads
    0
    Uploads
    0

    Default Re: Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

    Quote Originally Posted by wmgeorge View Post
    Nether one of my 3" square tubing mounting rails have caps anyway.
    Where I would propose the hole would actually be the tube directly under the linear rail. The ends are what the hard stops screw to. Borrowing PLJack's image here:

    https://www.cnczone.com/forums/attac...d=403344&stc=1Saturn 2 4x4 - Nema 23-2-jpg



Page 3 of 17 FirstFirst 12345613 ... LastLast

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Saturn 2 4x4 w/ Nema34 closed-loop - In Canada

Saturn 2 4x4 w/ Nema34 closed-loop - In Canada