Welcome to Our Community

Some features disabled for guests. Register Today.

YAPCNC (Yet Another Poor's Man CNC)

Discussion in 'CNC Mills/Routers' started by sergien, Jul 8, 2018.

  1. sergien

    sergien New
    Builder

    Joined:
    May 24, 2018
    Messages:
    5
    Likes Received:
    11
    sergien published a new build:

    Read more about this build...
     
  2. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Dec 20, 2013
    Messages:
    2,855
    Likes Received:
    1,525
    As this is just a temporary build with the intent of using it to cut permanent metal plates I would suggest bringing the X-axis down as close to the table as possible. This will increase the stiffness of the machine and improve its ability to cut metal. Other suggestions would include moving the Y-axis rails as high as possible (again to increase stiffness) and installing some glued and screwed solid wood inside corner blocks between the uprights and the X-axis beams to increase the strength of this connection.

    Happy building. Keep us updated.
     
    MaryD and sergien like this.
  3. Andreas Bockert

    Andreas Bockert Well-Known
    Builder

    Joined:
    Oct 1, 2017
    Messages:
    142
    Likes Received:
    78
    What are you planning to use for movement? Belt or screws?

    As Rick mentioned, you should to add some 90 blocks to the inside corners to increase stiffness. MDF/Particle board doesn't have great holding power for screws so it's likely that the screws crumble up the threads. So in addition to 90-blocks I would suggest using nut and bolts that go through both pieces to tighten them down.

    Those DRV8825 are more capable than you would expect. I ran my machine using 8825 with an old computer fan cooling them and had no problems.

    Good luck, it will be interesting to see how this progresses!

    Cheers,
    Andreas
     
  4. JustinTime

    JustinTime Veteran
    Builder

    Joined:
    Dec 18, 2013
    Messages:
    756
    Likes Received:
    252
    You could do as Rick suggested, lowering the y axis, or you could leave the two upright plates as long as they are but add a strip of 3" (or there about) particle board on each side of each of the plates creating an I beam. It will stiffen them up a lot!
    What Andreas said about the screw not holding well in particle board is correct. You can change it by either pre-drilling the hole and pouring some CA glue into the hole or screwing the screw in, taking it out, pouring some CA glue into the hole and after the glue dried screw the screw back in.
     
    sergien likes this.
  5. sergien

    sergien New
    Builder

    Joined:
    May 24, 2018
    Messages:
    5
    Likes Received:
    11
    Hi!

    First of all thanks for your improvement ideas. I really appreciate the contributions.

    Regarding the holding of the screws my idea is to use T-Nuts on the opposite side of the board (and washers on the screw side). That should hold the screws in place and overcome the problem of the holding power of the particle board.

    All the structure is to be reinforced with some strips to stiffen it up ... the actual photographs are from the initial "proof-of-concept" to see if my measurements hold the "reality" test.

    Now I'm waiting for the rest of pieces to arrive. I don't want to make more drills till the actual piece can be measured and see if it match the specifications.

    Cheers!
     
  6. MaryD

    MaryD OpenBuilds Team

    Joined:
    Apr 13, 2016
    Messages:
    649
    Likes Received:
    639
    Not sure if this will help but this steel tee nut will add threads to particle board

    690_steel_teenut_i_w_1.jpg 690_steel_teenut_s_w_1.jpg
     
    sergien likes this.
  7. sergien

    sergien New
    Builder

    Joined:
    May 24, 2018
    Messages:
    5
    Likes Received:
    11
    That is exactly the t-nuts I'm refering t .. I've used them on other projects and they work nicely.
     
  8. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Dec 20, 2013
    Messages:
    2,855
    Likes Received:
    1,525
    Yes, this will help reduce sidesway of the gantry frame but it won't reduce deflection of the cutting bit caused by unnecessary Z-axis length.
     
    sergien likes this.
  9. Giarc

    Giarc OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Jan 24, 2015
    Messages:
    2,899
    Likes Received:
    1,613
    Since all your plates are square, you could also just cut them out of aluminum and skip the temporary step. It is relatively easy if you have access to a table or chop saw. That is what I did. It was a fun challenge. Lead Screw Driven Ox Derivative (850x1500)
     
  10. sergien

    sergien New
    Builder

    Joined:
    May 24, 2018
    Messages:
    5
    Likes Received:
    11
    That's the problem ...

    The first reason is I've no access to a table saw (only commercial providers) so the cutting will be expensive.

    The second is I want to make sure everything works before going to the metal phase.

    Cheers!
     
  11. Giarc

    Giarc OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Jan 24, 2015
    Messages:
    2,899
    Likes Received:
    1,613
    Ok. I just assumed you had one since your wooden parts looked nicely cut.
     
  12. sergien

    sergien New
    Builder

    Joined:
    May 24, 2018
    Messages:
    5
    Likes Received:
    11
    Yup, but the provider cuts only wood on that machine ... as soon as you say metal, they say "Mmmm ... then our CNC should be used ... cost is 100€/hour ... minimum time is 1 hour and do not include materials" ...

    There is no rest for the wicked!
     
  13. Gary Caruso

    Gary Caruso OpenBuilds Volunteer
    Staff Member Moderator Builder

    Joined:
    May 19, 2016
    Messages:
    1,184
    Likes Received:
    531
    Sergien,
    You could easily use wide bar stock for these plates and cut with a hacksaw, or jigsaw :)
    That said, I do think there is a way to make this work out of Wood.. and I agree to lower the gantry for stiffness..
    Cheers
    Gary
     
    sergien likes this.
  14. GeoffH

    GeoffH Journeyman
    Builder

    Joined:
    Mar 11, 2017
    Messages:
    178
    Likes Received:
    106
    I see that you have received a lot of concerns about the gantry height, but from my point of view, larger z travel is very useful, of course unless you only want to cut flat plates. So I would carry on trying to stiffen the supports using your nouse! Good luck completing the project.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice