If you do edge coupled microstrip filters or directional couplers than the accuracy of the gaps is very important but another aspect that has to be considered is the roughness of the edges
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On Mar 18, 2022, at 21:04, Dave McGuire via groups.io <mcguire@...> wrote:
?On 3/18/22 21:57, Bryce Schroeder wrote:
Yes, it can hold 50 micron / 2 thou trace separation. I am in the
(slow) process of preparing a complete tutorial and open-source tool
chain. (It works, but actually using it at this point is quite an
undertaking for software reasons. I only just last year reverse
engineered the proprietary protocol used by the engraver:
) The calibration process is also
somewhat involved, but it's important (I imagine especially if you are
doing microwave filters and other things where the dimensions are
highly critical to be accurate not just precise.)
Nice! I'll look forward to your tutorial.
The engraver I'm using is an inexpensive (relatively) Chinese one.
They don't really have a brand name, but the control board is Beijing
Golden Orange (Bejing JCZ) and the laser source is usually JPT or
Raycus. A 20W one will work fine though 30 or 50 W should be faster.
They cost $2-3 grand, though, so this may be cost prohibitive if you
don't do a lot of PCBs.
I design probably twenty PCBs per year, so in-house prototypes would be a big deal here. I just try to interleave my tasks so OshPark's two-week delay doesn't impact me too much, but every now and then clients demand faster service. $2-3K would be difficult right now, since production runs have basically stopped due to component availability issues, but hopefully that will clear up before too long.
-Dave
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Dave McGuire, AK4HZ
New Kensington, PA
