Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
CO2 laser is the wrong wavelength to cut metal. Only a couple percent of the radiation is absorbed. Great for plastics, though, and many other materials. With respect to PCB etching, one thing I've thought about but haven't yet tried is simply using paint. Apply a thin code of flat black paint as a resist (I'm guessing enamel would work best) and let the laser ablate the paint where you want to etch. We already use commercial grade pre-photosensitized FR4 laminate, so doing painting and such is not needed. My only concern was that there might be issues of the wave-lengths between the LASER and the laminate being miss-matched, but if the process is actually based on heat then it is a non-issue. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
On Jan 24, 2010, at 9:39 AM, Dave N6NZ wrote: On Jan 24, 2010, at 4:43 AM, Bob Paddock wrote: CO2 laser is the wrong wavelength to cut metal. Only a couple percent of the radiation is absorbed. Great for plastics, though, and many other materials. With respect to PCB etching, one thing I've thought about but haven't yet tried is simply using paint. Apply a thin code of flat black paint as a resist (I'm guessing enamel would work best) and let the laser ablate the paint where you want to etch. We already use commercial grade pre-photosensitized FR4 laminate, so doing painting and such is not needed. My only concern was that there might be issues of the wave-lengths between the LASER and the laminate being miss-matched, but if the process is actually based on heat then it is a non-issue. Now that will depend on your photochemistry. CO2 laser is not in the visible spectrum. You'd have to check the sensitivity of the photo emulsion w.r.t. wavelength. Most litho films are not sensitive even to red, but do go up into ultra-violet. I can't remember if CO2 is longer or shorter than visible light. In any case, you'd get by with very low power. CO2 is way out in the IR. I guess the way to use it is to vaporize the resist. Note that black in the visible may not be black at the IR wavelength in question, and vice-versa. John Doty Noqsi Aerospace, Ltd. http://www.noqsi.com/ j...@noqsi.com ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Resend - Schematic Recommendations
This is a resend - Postmaster advised as undeliverable before. I Highly recommend the following: 1) Use Hierarchical design - I have worked on schematics ranging from a few sheets to a monster 390 C-Size sheets - USE HIERARCHY!! It will make your design flow MUCH Easier. 2) Use a consistent signal naming convention - I recommend that ONLY power nets have a V Prefix (example: V5P0 - for Positive 5 Volts, V15N0 for NEGATIVE 15 volts. A for AC.) Use a unique designator for special signals that have to be skew monitored, I also recommend C, D and A cor Clock, Data and Address, respectively. Whatever you choose - but document it IN the schematic (typically at a hierarchical top page. Name as MANY signals as you can. 3) Keep power and signal paths distinct - use a separate shape and separate sheet for bypass caps going to BABGAs (Big Ass BGAs!) - keeps your signal flow clean. 4) If you have special enable, select, timing generation, clock generation or unique support functions, put them on a separate page in your hierarchy - again, keep your signal FLOW clean! 5) Come in on the left, leave on the right, and mark if a signal is a gazinta, goesouta, a power or an eh? (bidirectional) 6) Use copious notes!!! You can place notes on a schematic - DO SO! 7) Make sure special RF Paths are noted (the PCB designer will keep grounds and signal paths as short as possible and use different layout techniques here) Remember - if you look at it three months from now and wonder what the hell you were doing, the first guy who looks at it NOW - OTHER than you - will wonder what the hell you are doing! Good Luck! ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
. Note that black in the visible may not be black at the IR wavelength in question, and vice-versa. For a different application I've been looking for 100% Black Paint for years, any one make it yet? -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/ ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
On Jan 24, 2010, at 9:15 AM, John Doty wrote: CO2 is way out in the IR. I guess the way to use it is to vaporize the resist. Note that black in the visible may not be black at the IR wavelength in question, and vice-versa Good point... I should have remembered that because I was part of the local robot club crew that built official IEEE micromouse maze bases, which specifies flat black IR absorbing paint on the maze floor. One of the guys was in charge of testing paint. I was on the ShopBot crew at the TechShop that's my excuse :) -dave ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
On Jan 24, 2010, at 8:39 AM, Dave N6NZ wrote: Now that will depend on your photochemistry. CO2 laser is not in the visible spectrum. You'd have to check the sensitivity of the photo emulsion w.r.t. wavelength. Most litho films are not sensitive even to red, but do go up into ultra-violet. I can't remember if CO2 is longer or shorter than visible light. In any case, you'd get by with very low power. So now for the wacky idea of the day... an interesting hack would be to make a tool head for a RepRap or some other cheap X/Y bed that simply holds a green laser pointer. That's very funny-- taking it full circle back to building a homebrew photoplotter, just like they use at the fab. :) There *have* actually been some DIY photoplotter projects, you just need to search for those separately. Here is one: http://blog.makezine.com/archive/2008/10/microcontroller_based_pho.html (And yes, the only use for CO2 in PCB fab is ablating resist layers. Exposing it is impractical.) ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Win32 hit list...
xgsch2pcb: Figure out the following for minipack: Building python for Win32 Building DBus / Win-dbus / whatever the working variant is on Win32 Building py-dbus (Python dbus binding) on Win32 How about using something like cxfreeze? http://cx-freeze.sourceforge.net/ Of the python - .exe builders I tried that was the only one I had success with. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Schematic Capture to dxf File - using gEDA, Inkscape, and pstoedit
On Jan 24, 2010, at 11:04 AM, Bob Paddock wrote: For a different application I've been looking for 100% Black Paint for years, any one make it yet? It's what they (whoever they are) point the cores of galaxies with ;-) John Doty Noqsi Aerospace, Ltd. http://www.noqsi.com/ j...@noqsi.com ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Win32 hit list...
On Mon, 2010-01-25 at 00:56 +0200, Duncan Drennan wrote: xgsch2pcb: Figure out the following for minipack: Building python for Win32 Building DBus / Win-dbus / whatever the working variant is on Win32 Building py-dbus (Python dbus binding) on Win32 How about using something like cxfreeze? http://cx-freeze.sourceforge.net/ Of the python - .exe builders I tried that was the only one I had success with. Neat, thanks.. I guess we'd still need to build the Win32 bindings for pydbus though.. since they are C linked, not native Python code. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
