584,833 active members*
5,717 visitors online*
Register for free
Login
IndustryArena Forum > WoodWorking Machines > DIY CNC Router Table Machines > Would like to get thought on CNC machine design
Page 2 of 2 12
Results 21 to 29 of 29
  1. #21
    Join Date
    Nov 2008
    Posts
    644

    Re: Would like to get thought on CNC machine design

    That appears to be the way to go Peter. The slide base can’t get in the way. Great Z travel. I like it.


    Sent from my iPhone using Tapatalk

  2. #22
    Join Date
    Jul 2018
    Posts
    6248

    Re: Would like to get thought on CNC machine design

    Hi Jerm - Here is Scoot from the front. Scoot is my first high rail build. I'm very impressed with its stiffness. And it contains dust really well.... Highly recommend a high rail design.... Peter

  3. #23

    Re: Would like to get thought on CNC machine design

    Quote Originally Posted by peteeng View Post
    Hi Jerm - Here's an image of my Z axis on my machine called Scoot. Shows the rails on the z axis not the saddle. I have tidied the wiring since that photo Peter
    I am doing exactly that on this one thanks!!!!

  4. #24

    Re: Would like to get thought on CNC machine design

    Quote Originally Posted by peteeng View Post
    Hi Jerm - Here is Scoot from the front. Scoot is my first high rail build. I'm very impressed with its stiffness. And it contains dust really well.... Highly recommend a high rail design.... Peter
    I understand the high rail design now. That makes way more sense and I think simplifies the issue I was running into with arms the gantry. Thanks for the photo, So I can build a steel table frame, put the mount rails high up like that and really remove a ton of the moment arm from everything.

  5. #25

    Re: Would like to get thought on CNC machine design

    I took some ques from your high axis machine and got the design more solidified. I designed a new Z-axis from scratch using linear rails and have one massive plate to get machined that holds the Z and Y axis together. I have 8.8" of clearance from the table to the collet of the spindle and Z travel to match. I know you will yell at me for using the aluminum extrusion but it will help me so much in assembly and being able to align things I gotta use it. The X-Y axis attachement I am used some welded angle iron to give it some beef and give the gantry some reinforcement. I gotta deal with the floating Z motor (need to design a motor mount, and then finish up the table and I should be ready to cost this thing out and see if dreams can become reality.

    One thing, have any of you had success using Nema 23 motors on a frame this size or should I bite the bullet and get the Nema 34s?

    here is an updated photo and a link to the updated 3D design.

    https://a360.co/3JHu2DI

  6. #26
    Join Date
    Jul 2018
    Posts
    6248

    Re: Would like to get thought on CNC machine design

    Hi Jerm - N23 are fine. Cheaper to buy a motor mount, you have one on the other axis? Peter

  7. #27

    Re: Would like to get thought on CNC machine design

    Quote Originally Posted by peteeng View Post
    Hi Jerm - N23 are fine. Cheaper to buy a motor mount, you have one on the other axis? Peter
    Yes, Will end up doing just that. The motor mount I have on the others I found a nice one that spaces out the front bearing of the ball screw and motor mount all in one. That didn't fit on the Z
    so I will just get the smaller motor bracket. Its just bed time so I haven't dealt with it.

  8. #28

    Re: Would like to get thought on CNC machine design

    Got an update on this. Did some math and rough cost will be $3,000 for the whole machine. I'm sure I am missing stuff so lets call it $4,000 once I find all the small details I missed. Just finished creating drawings for all the custom components and sent them to a buddy with a machine shop. Figures crossed it doesn't come back outrageous. Gotta do some searching on a different spindle than the one I had on here. After doing some more research, I don't like how small the collet and bearing are on this one (ER11 instead of ER 20), so if you got any ideas on a 1.5-2.2 kW spindle with VFD for $500-600 I am all ears.

    Here is the latest 3D model. Not much changed except the side rails are 2"x4" instead of 1x4. Haven't spent much time on the green table, that will be easy for me to source and fab so only need rough dimensions.
    https://a360.co/3JHu2DI

  9. #29
    Join Date
    Jul 2018
    Posts
    6248

    Re: Would like to get thought on CNC machine design

    Hi Jerm - The extrusion used for the saddle and Z axis is actually not very stiff and having all those thin edges is prone to vibrate. A steel or solid aluminium plate with deep flanges will do much better for the Z axis. It needs to be really stiff to resist fwd and rearward loads... Or laminate the extrusion with 6mm aluminium each side, glued together...or bolt on deep side flanges. Same for saddle, put flanges on it ot make it thinker. When the tool pushes backward and fwd the saddle will bend at the top bearing as its cantilevered.

    Maybe instream of separate spacers under the cars they can be continuous to improve the bending stiffness of the saddle. The car screws in the middle can have deep counterbore or use long screws...

    Plus your better off having the z axis bearings below the gantry bearings to reduce the cantilever length. Then the columns will need to be a little higher but thats OK you need max Z stiffness. OK Peter

Page 2 of 2 12

Similar Threads

  1. DIY CNC Mill - Playing around with the thought
    By DuxEtCapital in forum Uncategorised MetalWorking Machines
    Replies: 35
    Last Post: 10-30-2018, 12:58 AM
  2. Replies: 0
    Last Post: 09-24-2018, 10:41 PM
  3. New Machine Design book from Alexander Slocum (of Precision Machine Design)
    By toastydeath in forum Uncategorised MetalWorking Machines
    Replies: 10
    Last Post: 11-25-2009, 05:37 PM
  4. Thought / opinions on this cnc kit
    By chola in forum Stepper Motors / Drives
    Replies: 0
    Last Post: 03-17-2009, 10:13 PM
  5. Thought on Design found on Ebay
    By dfranks in forum DIY CNC Router Table Machines
    Replies: 17
    Last Post: 10-11-2007, 08:32 PM

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
  •