515,153 active members
2,907 visitors online
Register for free
Login
Page 2 of 2 12
Results 21 to 34 of 34
  1. #21
    Registered
    Join Date
    Oct 2005
    Posts
    41
    A couple of pictures of a board I made tonight.

    Dave[IMG][/IMG]

  2. #22
    Registered
    Join Date
    Oct 2005
    Posts
    41
    oops! here's the other side:

  3. #23
    Registered
    Join Date
    Sep 2009
    Posts
    104
    are you guys using Opti on the code generated by pcb-gcode.ulp?

    it definitely cleans up the toolpath, but there is a TON of z axis movement. there is definitely no need for it to move sometimes and it could just continue cutting. i have mastercam but i have no idea how to use it yet. is there a better way to generate a toolpath because pcb-gcode seems incredibly rough around the edges. i made a pretty simple board and counted 109 extraneous z axis movements. that is kind of ridiculous, right?

  4. #24
    Registered
    Join Date
    Dec 2004
    Posts
    1137
    Quote Originally Posted by bandtank View Post
    are you guys using Opti on the code generated by pcb-gcode.ulp?

    it definitely cleans up the toolpath, but there is a TON of z axis movement. there is definitely no need for it to move sometimes and it could just continue cutting. i have mastercam but i have no idea how to use it yet. is there a better way to generate a toolpath because pcb-gcode seems incredibly rough around the edges. i made a pretty simple board and counted 109 extraneous z axis movements. that is kind of ridiculous, right?
    PCB-Gcode processes the poly-line "paths" from Eagle as they were drawn. Then depending on your settings, it generates additional paths to give you the isolation, iterating per the step distance. These paths are then strung together and written to a file. Opti finds these paths and using nearest neighbor rearranges them keeping the original first and last paths in their same place. It's fast and it saves a lot of Air moves. To speed things up more, you can set you Z-up parameter in PCB-Gcode to something like .01 so each retract is minimal. if you think 109 Z moves it bad, have a look at the Gcode before Opti

    Also, Opti source was also released so you are free to improve it. Yes it's rough, it's open source and freeware done for personal use and released to the public

    How are you going to get the the DXF of your circuit to even run the CAM against it? There might be a ULP for that I suppose but it seems like a more complex tool chain.

    -Jay

  5. #25
    Registered
    Join Date
    Sep 2009
    Posts
    104
    I didn't ask my question very well. I appreciate your response, but I knew most of that after reading several forums and webpages about both pcb-gcode and opti. However, something I haven't seen posted is the way pcb-gcode interacts with polygon planes. All of the extra z movements went away when I deleted the ground plane on my own board. I also downloaded the eagle files from the LPC mini and ran pcb-gcode on them without making any changes. The resulting gcode was very broken and I used the default options. The isolation distance seemed to make a difference on my board a little bit but it didn't seem to help on the LPC mini board. The pcb-gcode readme.html makes no mention of how ground planes are treated.

    The problem is not opti. I made several boards with varying complexity and pcb-gcode is behaving non-deterministically depending on what is done with polygons. I can post some pictures of the resulting gcode movements as seen inside Mach3 and it's like random, large pieces of the code are just missing. I think I understand that pcb-gcode wants to handle the trace isolation on it's own, but there should be documentation describing what it will do if you use polygons for ground and power planes. As an example of where this is confusing me at the moment, how will it know how to treat an analog ground plane that needs to be a specific shape if I can't actually draw it?

  6. #26
    Registered
    Join Date
    Sep 2009
    Posts
    104
    Here are some pictures. I have not been able to generate a toolpath like the one you posted of the LPC mini with all of the pads of the microcontroller explicitly cut out. I must be missing a setting.

    Pic 1 = LPC mini with no changes (ground plane isolate = 0)
    Pic 2 = LPC mini with ground plane isolate = .02"
    Pic 3 = LPC mini with ground plane isolate = .04"
    Pic 4 = LPC mini with no ground plane
    Pic 5 = pcb-gcode settings page 1

    I changed the tool size from .01" to .005" and the toolpath got much, much better, but I still don't understand how it is interacting with the ground plane.

    Also, pcb-gcode is generating comments in the gcode file that do not work with Mach3. I made sure I clicked on the Mach profile in the pcb-gcode setup and unchecked the boxes for comments on the next tab. It is still inserting them at the top of the file and Mach will not even load the toolpath unless I delete the comments. It is also putting "(File Footer)" near the bottom which must be deleted as well. I posted on the pcb-gcode yahoo group but it seems pretty dead as I got no responses. Any ideas?
    Attached Thumbnails Attached Thumbnails Capture.JPG   Capture.2JPG.JPG   Capture3.JPG   Capture4.JPG  

    Capture5.JPG  

  7. #27
    Registered
    Join Date
    Dec 2004
    Posts
    1137
    The error for the comments, does sit say "nested comments"? If so it's because you have a parens inside another parens. I started getting this error when I moved to Windows 7 and installed pcb-gcode into the Program Files (x86) directory tree.

    What is the isolation set for on the ground plane in Eagle? PCB-Gcode will not try to fit an endmill where it will not fit. Thus if your endmill were 0.01 and you need to clear a .008 space between pins, it' will not work. The end mill I have is .005" so I am able to do TQFP. You do get what you pay for and thus if you wanted to use multiple tools, you would have to run PCB-Gcode for each one. I would start with the biggest and move to the smallest with isolation for PCB-Gcode set to off (min = max = .0001). Have a look at MillPCBs.com for his analysis of settings too.

    Also, the step size of .001 seems a bit much, what size is your endmill? I would go 40 to 50% of that.

  8. #28
    Registered
    Join Date
    Sep 2009
    Posts
    104
    Quote Originally Posted by Jay C View Post
    The error for the comments, does sit say "nested comments"? If so it's because you have a parens inside another parens. I started getting this error when I moved to Windows 7 and installed pcb-gcode into the Program Files (x86) directory tree.

    What is the isolation set for on the ground plane in Eagle? PCB-Gcode will not try to fit an endmill where it will not fit. Thus if your endmill were 0.01 and you need to clear a .008 space between pins, it' will not work. The end mill I have is .005" so I am able to do TQFP. You do get what you pay for and thus if you wanted to use multiple tools, you would have to run PCB-Gcode for each one. I would start with the biggest and move to the smallest with isolation for PCB-Gcode set to off (min = max = .0001). Have a look at MillPCBs.com for his analysis of settings too.

    Also, the step size of .001 seems a bit much, what size is your endmill? I would go 40 to 50% of that.
    why would a step size of 1mil be a bit much? i milled several boards today and had perfectly good results using step sizes as big as the cutter engagement into the material, which makes perfect sense. the problem is with polygons and im getting very non-deterministic tool paths regardless of what i do with the isolation and cutter sizes. maybe what im trying to do is too complex for the ulp or something, i dont know, but its not working very well with what im trying to do and i know how to use it at this point after messing around for several hours.

    i attached a picture of a test cut i made in a piece of aluminum. that is a 0.4mm pitch qfp footprint. i can live with these results for now. ill keep working on it and see if i can nail down exactly what the problem is.
    Attached Thumbnails Attached Thumbnails IMG_8873.jpg  

  9. #29
    Registered
    Join Date
    Dec 2004
    Posts
    1137
    oops, I meant too small and thus multiple paths where there could have been fewer to achieve the same isolation paths.

    Quote Originally Posted by bandtank View Post
    why would a step size of 1mil be a bit much? i milled several boards today and had perfectly good results using step sizes as big as the cutter engagement into the material, which makes perfect sense.

  10. #30
    Registered
    Join Date
    Dec 2004
    Posts
    1137
    Quote Originally Posted by bandtank View Post
    I posted on the pcb-gcode yahoo group but it seems pretty dead as I got no responses. Any ideas?
    try www.pcb-gcode.org John moved there after yahoo went down several times. There is not a lot of activity there either.

  11. #31
    Gold Member
    Join Date
    Mar 2004
    Posts
    1800
    JJ has responded to some of his concerns on the yahoo group.

    One problem with his request was yahoo! Notification of both of his posts arrived at the same time. I have noticed on a few of the groups of seriously delayed notification of posts/membership requests and also just plain posts getting to groups.
    Art
    AKA Country Bubba (Older Than Dirt)

  12. #32
    Registered
    Join Date
    Sep 2009
    Posts
    104
    Quote Originally Posted by Bubba View Post
    JJ has responded to some of his concerns on the yahoo group.

    One problem with his request was yahoo! Notification of both of his posts arrived at the same time. I have noticed on a few of the groups of seriously delayed notification of posts/membership requests and also just plain posts getting to groups.
    He did respond and, while I appreciate that, his answers didn't really help.

    I am collecting more data about the polygon issue. I'll post about that again when I know more about what the problem is.

    The comment issue he said was because I may have enabled user gcode, but I didn't. The comments causing the problem are the defaults that are inserted regardless of any options I enable or disable. To answer the previous question, yes, it does say nested comments. If you were able to fix this, how did you do it?

  13. #33
    Registered
    Join Date
    Dec 2004
    Posts
    1137
    Quote Originally Posted by bandtank View Post
    To answer the previous question, yes, it does say nested comments. If you were able to fix this, how did you do it?
    The permanent fix is to move/re-install PCB-gcode in a directory without any parens in the name. You will also need to update Eagle so it know to look in the new PCB-Gcode directory for the ULP.

  14. #34
    Registered
    Join Date
    Feb 2009
    Posts
    1290
    Hey guys when you post your pictures it would be nice to get some info on how you made the board like software used, router bit, DOC, what type of PCB material and the thickness of the copper. Hold down method might help new users get an idea of what might help.

Page 2 of 2 12

Similar Threads

  1. Tinning PCB's ???.
    By epineh in forum General CNC Machine Related Electronics
    Replies: 10
    Last Post: 07-24-2012, 10:57 PM
  2. Help with aluminium bed for pcb's
    By djh82uk in forum Hobby Discussion
    Replies: 8
    Last Post: 11-20-2007, 08:53 AM
  3. Blank PCB's available
    By pminmo in forum Open Source Controller Boards
    Replies: 13
    Last Post: 09-14-2005, 10:27 PM
  4. CNC & PCB's
    By Imagineering in forum General CNC Machine Related Electronics
    Replies: 6
    Last Post: 08-15-2005, 04:05 PM
  5. Lasering PCB's?
    By Xerxes in forum General Laser Engraving / Cutting Machine Discussion
    Replies: 2
    Last Post: 08-12-2005, 02:13 PM

Posting Permissions

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