Re: Can only get a single isolation pass around tracks #eagle #pcbgcode #etch

Bernardc
 

Assume that you not use SMD on your PCB as etching with 0.9 mm….

Autoleveler is perfect to correct the copper default. I use 2 flutes V type 60° dia 0.127 mm with 0.05 mm depth and it is not necessary to make further pass.  Mini = 0.0254, Max = 0.762, Step = 0.0508, Feedrate = 400, Turn = 12000 T/mn. I can etch for SSOP. (The problem remains welding ;-)..)

 

Bernard  

 

De : pcbgcode@groups.io [mailto:pcbgcode@groups.io] De la part de Rick Obel
Envoyé : lundi 20 août 2018 17:32
À : pcbgcode@groups.io
Objet : Re: [pcbgcode] Can only get a single isolation pass around tracks

 

My approach is very similar to Sam’s, but three differences that I believe help:

1.       Immediately before cutting a PCB, I pre-level my sacrifice board, which is MDF.  I believe that the MDF warps over time, even though I rarely remove it, or even adjust it.

2.       I don’t use angled bits (sorry I don’t know the correct terminology).  Instead, I find that conventional end mills produce a cleaner, more consistent cut.  I am still experimenting with diameters, but find 0.6mm breaks easily, while 0.9 is unnecessarily wide.  Lately, I have been using 0.7mm but will focus on 0.8 next.

3.       If the incomplete etching (is that the right word?) is localized, I will re-run just those areas at a deeper depth.

Rarely do I need three passes, and a second pass is only required about half the time.

-Rick

 

From: pcbgcode@groups.io [mailto:pcbgcode@groups.io] On Behalf Of sdmonaco via Groups.Io
Sent: Monday, August 20, 2018 7:56 AM
To: pcbgcode@groups.io
Subject: Re: [pcbgcode] Can only get a single isolation pass around tracks

 

Hi Albert,

 

You might try my single pass etch approach, which I now use for all of my boards.  I setup pcb-gcode to do a singe pass etch for all traces and shapes.  After completion, I inspect the board without removing it from the fixture.  If I see any areas with incomplete etching, I lower my z-axis zero point by 2 mils and re-etch the board with the same gcode file.  I continue with this until I have a nicely etched PCB which usually only takes about 1 to 3 passes.  This approach also corrects most leveling issues as well.  I try to keep my trace widths over 12 mils because each pass will shrink your trace width by about 1 mill for a 30 degree spade bit.

 

Sam

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