Hi Steve and all,
I to have had many of the same problems you had. I would say that I'm
still just a beginner and hopefully there are other experts who can help us
with a lot of these "reality" details. The engraving machine we have at
work here (XENETEC XOT 25" X 50", approx $13K) is good for tags, plaques
etc. It does not transfer at a 1:1 scale and this makes it very hard to get
a good end product sundial. They intend to fix that problem on the next
release of software. There are several local high end engravers I talked to
(not plaques), but they were quite expensive, due to the one of a kind
programming required for individualized dials. I therefore also ended up at
my local high tech machinist who uses his $300K machining center, and only a
moderate amount of time, to finalize the DXF file. The quality is great but
at a moderate cost, say $50 to $200 depending on complexity.
Someone recently mentioned New Hermes engravers (top of the line).
Their
machines are about $20K for a mid range "IS 6000", 16" X 24" with mid range
software. I'm looking for a So. Cal. job shop with one (or similar) who
would be able to do one of a kinds reasonably.
I would think that photo etching would be good on production runs like
the
nice portable, universal ring dial from Austria, which Fred Sawyer had at
the San Francisco conference. I assume that a modest $50 or so for photo
work similar to the photo metal I had done, and then the etching would be
reasonable. I don't know how costly or depth of etch details etc.
With fonts, I am not too familiar with DeltaCad, but possibly it has a
simple line font which is explode-able? What I had to do in AutoCAD R13 was
trace a series of short connected lines over each letter and then erase the
font. AutoCAD R14 supposedly has a feature to explode text, but I don't
know if the results will be what we hope for; I would expect lots of
scale/rotation etc problems. Also, most (?non true?) fonts are made up of
many lines and curves, which might make for a very complex machine path
(+$$).
The DXF is a good transfer medium for 2D drawings, though it seems it
must
be "cleared" of all but lines. As far as I know, it only transfers lines (a
tool path). This is the reason you need to fully explode everything and
then purge all layers thoroughly to remove all of the non-line information.
This leaves a clean, line only, drawing which will transfer back and forth
clearly. I have always just told the shop what depth I want, for each of
the lines. Maybe a newer transfer language might allow you to have the tool
depth (line width) as another variable attached to each line, I believe they
call it 2-1/2 D (instead of 3D). I've also heard that you can place
increasingly deeper engravings on separate layers which automatically index.
I hope this has been of some help, but I know we need some real experts
to
optimize our path from cad to "reality".
Fritz
