586,570 active members*
3,670 visitors online*
Register for free
Login

Search:

Type: Posts; User: slow-poke

Page 1 of 2 1 2

Search: Search took 0.00 seconds.

  1. Re: Please critique this concept and suggest a suitable timing belt

    I don't have an easy way to weigh my mill, the shipping paperwork stated 2000lbs, so a bit under that best guess. 300kg would be a good estimate for everything on the knee. Ballscrew is 5mm pitch.
    ...
  2. Re: Please critique this concept and suggest a suitable timing belt

    Craig,

    I appreciate the feedback, my A1S knee mill is fair bit larger/heavier than your mill. I measured the torque required to lift the knee with the existing leadscrew (no weight other than a...
  3. Re: Please critique this concept and suggest a suitable timing belt

    Peter,

    I found some suitable pulleys on McMaster-Carr. so I'm going to take a crack at printing them for trial fit and who knows perhaps they will be strong enough to try out the concept.

    Much...
  4. Re: Please critique this concept and suggest a suitable timing belt

    Peter,

    Much appreciated, I will pick something suitable from the catalog now that I know what to look for.

    One step closer, have a great day!
  5. Please critique this concept and suggest a suitable timing belt

    I'm more of an electrical type guy than a mechanical type guy so fairly clueless on selecting a suitable belt for this application.

    I have the x and Y axis doing their thing with ac servos and...
  6. Re: Angular Contact Bearings - any experts out there?

    Thanks,

    That's helpful.

    I ordered the P4's off eBay, the seller accepted my $50 offer, so they should be on their way shortly.

    One of my buddies tells me the way he sets the preload on these...
  7. Re: Angular Contact Bearings - any experts out there?

    Craig,

    Thank you for the links.

    I still have one more question....

    My understanding is that these bearings will either have slightly wider inner races, or slightly wider outer races, and...
  8. Re: Angular Contact Bearings - any experts out there?

    Search for matched 12x28x8mm angular contact bearings is not yielding much, source?
  9. Angular Contact Bearings - any experts out there?

    I'm on a quest to get the backlash on my machine under 0.001" or as close as reasonably possible.

    This is an older 8x30 knee mill with new Chinese rolled 1605DFU ballscrews and double nut.

    With...
  10. How many balls should there be in a ballscrew circuit?

    I have a double (anti-backlash) nut (1605) that was removed from a ballscrew and the balls went everywhere. I think I rounded most of them up but who knows? In total I have 31, so say 5 per circuit....
  11. Max velocity and Acceleration - or how not to beat your ballscrews to death?

    My past CNC conversions used stepper motors so were inherently slow.


    My latest conversion (8x30 Knee mill) with DFU2005 and DFU1605 ballscrews uses 750W ac servos, These are a world different...
  12. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    A transformer in buck mode can actually be reasonably small because the vast majority of the current only flows in one 20V secondary winding. The $20 transformer (visible in the control box image...
  13. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    The drive has a factory set upper limit alarm (that shuts the drive down) at 242V.
  14. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    Craig,

    For reliability we don't design to nominal voltages, we design to worst case, as stated the utility specified tolerance is 240V + 6% , resulting in 360Vdc, These drives have a 350V bulk...
  15. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    According to tech support, you should under no circumstances exceed the absolute maximum of 242V, and in fact the over voltage alarm in the drive will be triggered at that level. This is not a Delta...
  16. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    I thought I should provide an update on this servo selection thread I started now that I have selected and installed some of the servos.

    I decided to take a chance with StepperOnline T6 ac servo....
  17. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    I'm not sure what's up with the leadshine website, but when I tried to access to download the EL6 manual etc. MalwareBytes warns me that it's not safe and is attempting to place a trojan on my PC. I...
  18. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    I would actually enjoy digging into manual tune for educational purposes if I could get useful answers to my questions from tech support. So far the responses have been polite but rarely answer the...
  19. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    Craig, Wes

    Craig, thanks for the confirmation on Jlinear. Your point about the inertia contribution makes complete sense. I vaguely remember doing these calculations in first year (1980's)

    I'm...
  20. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    Craig,

    Your thoughtful response is much appreciated. The inertia ratio was just a pie in the sky value that I entered to see what would happen. Picking up from your example, I’m going to focus on...
  21. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    Perhaps I'm getting old and slow but I find the documentation for MotionStudio to appear at first glance to be simple and straightforward, however when actually using it it's not clear what the...
  22. Re: Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    Response curve as is:
  23. Is anyone using Leadshine or Stepper Online ac servos - Tuning guidance required

    My control theory (PID loops etc.) is long forgotten it was 40 years ago. My understanding is that ac servos are a bit more finicky to tune than dc servos partially because they have wider bandwidth...
  24. Replies
    2
    Views
    368

    Re: CNC user interface

    Good point. I have been busy with ballscrew and servo modifications (almost complete) and so I'm thinking ahead to next steps. With my old mill I used a touchscreen but much preferred using actually...
  25. Replies
    2
    Views
    368

    CNC user interface

    Years ago I converted an old round column mill to CNC, at the time I was not thrilled with the pendants available and the thought of the pendant constantly falling on the floor etc so I made a custom...
  26. Replies
    18
    Views
    1,776

    Re: MACH, Linux CNC, Acorn, UCCNC, other?

    Craig,

    Thank you for taking the time to post a fantastic and informative response. I particularly like this point:

    There are very strong and vociferous adherents of each of these solutions,...
  27. Replies
    18
    Views
    1,776

    MACH, Linux CNC, Acorn, UCCNC, other?

    I need to make a decision on CNC software for the new mill. I have used Mach3 in the past, so I'm quite familiar with it. Some obvious competitors are Linux CNC , Acorn, UCCNC, others?
    ...
  28. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    I contacted DMM, they want US$600 per axis, that would be CDN$3300 and that's more than I paid for the entire mill.


    I did find T6 series ac servos at stepperonline...
  29. Replies
    27
    Views
    1,855

    Re: 8 x 30 knee mill servo selection

    joeaverage,

    Thanks for that. I'm located in Canada so I should probably look at the DMM brand.

    Anyone have experience with DMM servos?
  30. Replies
    27
    Views
    1,855

    8 x 30 knee mill servo selection

    Newbie here.

    Preamble:

    This is for hobby use not professional.

    I have two manual mills, I converted one of them to CNC about 10 years ago using NEMA34 steppers and using Mach3 to control. I...
Results 1 to 30 of 31
Page 1 of 2 1 2