toggle quoted messageShow quoted text
I tend not to depend on the board to be square. As part of machining the first side I’ll drill four 1/8” holes just outside of the board footprint and centered on the board. The holes go down into my cast acrylic baseplate at least ¼”. Then when I flip the board I can use four 1/8” bit shanks to align the board.
From: pcb-gcode@... [mailto:pcb-gcode@...]
Sent: Sunday, December 20, 2015 10:02 AM
Subject: Re: [pcb-gcode] Cutting out the board !!
I've found quite a few of my (admittedly cheap-assed) boards to not be especially square on every edge. This seems like it might play havoc with the flip (I've made a bunch of single sided boards, will embark on 2-sided soon). Is this a common problem or did I just choose especially poorly in my eBay supplier of choice?
Sounds like it should do it.
At 05:24 AM 12/20/2015, you wrote:
just to get it clear for me...
I mill a pocket 200x200mm on my tabel.Â
1. in the left corner I set my X+Y zero
2. put he pcb in the left corner.
3. I do theÂ .top.etch.tap job
4. I flip the board and placed in right corner.
5. I jog the X to +200 and hit the zero.
6 I do theÂ .bot.etch.tap.
In my case, the "fixture pocket" is permanently fixed to my table and I use G55 work offset for the bottom of the board, and G55 work offset for the top of the board.Â And I knew the coordinates of the left and right corners when I milled the pocket, these offsets are known and were pre programmed into my setup routine. Therefore when I start up the machine and home it, the routine goes to home position and now knowing where it is, it proceeds to the G54 work offset position (in G53 absolute coordinates) where we set its origin with a G92 command.Â Then we proceed to the G55 origin again in G53 absolute coordinates and set it.
Now when doing the pcb, we only have to concern ourselves with setting the Z axis top of the board!
At 02:13 PM 12/19/2015, you wrote:
Ã‚ "milled a shallow pocket" was very clever.... then your "flip-line" is close to 0
and if you use a "triple edge finder" it is very easy to find your Zerro in X:Y:Z
maybe do a "pocket" that can fit a 100x160mm card...I think it is ok for me...
When you start doing the bottom processes, the Origin (X0 Y0) is the lower RIGHT corner of the board.
When you do a normal flip of the board (along the Y axis), the Origin is now in the LEFT corner of the board.
You can do your alignment several ways, but the two most common are to use "Registration Pins" or to align the board by the origin corner and along the lower side.
In my case, I have a fixture that I milled a shallow pocket into and by milling it, I know exactly where the lower corners of the board will be when I place the board in the pocket.Ã‚Â
At 12:47 PM 12/19/2015, you wrote:
Just fine, I will make the tracks at "46 layer" and I will make some cut int the track so my pcb do not get in to aÃƒ‚ booomerang
now I just have to figure out how to make double side pcb...having the same start X & Y.... so that the hole is in the pad and notÃƒ‚ next to
You can generate a "mill" file which will cut the outline of the board.
As noted in the manual (pdf file found in the docs folder of the original zip file),
"Generate milling Generate g-code for any wires the user has drawn on the Milling
(46) layer. Depth sets the milling depth."
In other words, put wires on the Milling layer (46) and do the necessary checking of the "generate mill file" in the setup ulp along with the depth of cut and it will mill out your board. Be absolutely sure this is the last file you run or your board will be separated from the stock and no further operations will be available!Ãƒ‚Ã‚Â Also, not knowing what your spindle ppower is, you may not be able to do the full depth in one pass and this ulp only allows one pass milling.Ãƒ‚Ã‚Â Further, you might not outline thee entire board and leave some "tabs" so the board doesn't flip out and possibly become damaged (don't ask how I know this one!)
Another option would be to cad up the outline and cam it in your normal cad cam programs if you have any.Ãƒ‚Ã‚Â
Hope this helps,
Ãƒ‚ At 10:35 AM 12/19/2015, you wrote:
After made som good pcb , I need a hint how to cut out the board ?? PCB-Gcode do not
make this code ??? ore something I cant see in the menu ...
Content-Type: application/octet-stream; name="2dae23c5.png"
Content-Disposition: inline; filename="2dae23c5.png"
Content-Type: application/octet-stream; name="2dae23b5.png"
Content-Disposition: inline; filename="2dae23b5.png"