Re: Homemade PCBs!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Crow Leader" <tesla-at-lists.symmetric-dot-net> 

There are air insulated boards that work at that voltage with no really
special construction aside from being long, and having the high voltage
spaced evenly across the board. You don't want 15kV traces running next to
each other, but say 750 volts trace to trace may be fine.

KEN


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, April 26, 2004 8:41 AM
Subject: Re: Homemade PCBs!


 > Original poster: "David Brown" <davidncbrown-at-hotmail-dot-com>
 >
 >
 > It will be hard to make a pcb insulated at 12KV.  There will also be
 > capacitance between traces at that voltage.
 >
 >
 >
 >
 > Original poster: "Hydrogen18" <hydrogen18-at-hydrogen18-dot-com>
 >
 > I'm going to try something soon...any tips on making a PCB insulated to
 > 15000 volts?
 >
 > Also on the subject of CNC routers...they can be made cheap. Search the
web.
 > For prototyping purposes btw, you could use a drill press and a routing
bit.
 >
 > ---Eric
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Sunday, April 25, 2004 5:00 PM
 > Subject: Re: Homemade PCBs!
 >
 >
 >  > Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net>
 >  >
 >  > Having been through both approaches in a va! riety of environments, I
have
 > the
 >  > following observations:
 >  > 1) If you have the room to make the boards (including exposures, etc.)
and
 >  > do it often enough that your process skills remain fresh, there is a
 > certain
 >  > appeal to being able to zap out a board "on impulse".  Draw the
circuit,
 >  > make the board, solder the parts, and be testing in a couple hours.  20
 >  > years ago I bought a big stat camera which can do 1:4 reductions just
for
 >  > this sort of thing.  Too bad I don't make enough boards to keep the
 >  > chemicals and film fresh, much less my photographic skills.  The camera
 >  > sits, unused, in my garage.
 >  >
 >  > 2) The commercial products will almost always turn out better (unless
 > you're
 >  > a business where prototyping is part of the day to day work).  While
 > making
 >  > good quality two layer boards is fairly straightforward, drilling by
hand
 > is
 >  > a pain, decent robotic drills are expensive (more than a kilo! buck,
 > although
 >  > I'd love to hear about a cheaper one), and doing plated through holes
is a
 >  > real pain.  Then there's the solder mask and silkscreen..
 >  >
 >  > 3) On a cost basis, they'll probably turn out about the same, within
the
 >  > significance of the measurement.  More dollars invested up front (or
time
 >  > scrounging equipment and materials) for home fab, but fairly low piece
 >  > costs.
 >  >
 >  > 4) Multilayer (4 or more) are not real feasible for home fabrication.
It
 > can
 >  > be done, but process controls are tough. There's also the problem of
 > minimum
 >  > order quantities for things like prepreg.
 >  >
 >  > 5) A very attractive alternative for a lot of prototyping is the
computer
 >  > controlled router approach.  It will do the traces, and do the holes.
 > Won't
 >  > do the plated through, but it's definitely a hot ticket for RF
 > prototyping.
 >  > A tad pricey (! again, if someone knows of a decent (assembled) system
for
 >  > un der $1000 (exclusive of PC), I'd love to hear about it).
 >  >
 >  > 6) There are some interesting approaches I've seen commercially, but I
 >  > haven't seen in hobby applictions, although I think they'd be
appropriate.
 >  > Things like the "multiwire" where it essentially "plots" a special
 > insulated
 >  > wire onto the substrate, or various stereolithographic schemes (like
the
 >  > computer controlled glue gun things).  I've also seen systems (based on
 > the
 >  > same scheme they use for making custom vinyl signs) that cut copper
foil
 > on
 >  > a backing, which is then "glued" to a substrate.  Peeling the unused
 > copper
 >  > away doesn't strike me as a lot of fun (like peeling rubylith!) but
might
 >  > give good results.
 >  >
 >  >
 >  > ----- Original Message -----
 >  > From: "Tesla list" <tesla-at-pupman-dot-com>
 >  > To: <tesla-at-pupman-dot-com>
 >  > Sent: Saturday, April 24, 2004 6:55 PM
 >  > Subject: Re: Homemade PCBs!
 >  >
 >  >
 >  >  > Original poster: "Jim Mitchell" <Electrontube-at-sbcglobal-dot-net >
 >  >  >
 >  >  > Or for about the same price it costs to get all the materials and
 > things
 >  > to
 >  >  > do photo etching,  you can have 10, 3X5 soldermask and silkscreened
 > boards
 >  >  > for 65$....
 >  >  >
 >  >  > Regards - Jim Mitchell
 >  >  > ----- Original Message -----
 >  >  > From: "Tesla list" <tesla-at-pupman-dot-com>
 >  >  > To: <tesla-at-pupman-dot-com>
 >  >  > Sent: Saturday, April 24, 2004 8:53 PM
 >  >  > Subject: Re: Homemade PCBs!
 >  >  >
 >  >  >
 >  >  >  > Original poster: Matthew Smith <matt-at-kbc-dot-net.au>
 >  >  >  >
 >  >  >  > Eric ("Hydrogen18") writes:
 >  >  >  > >I'm looking to make some homemade PCB's for a voltage
multiplier,
 >  > whats
 >  >  >  > >the best way to do thi! s? I've seen those kits where you draw
 >  > everything,
 >  >&n
 > msnip...
 >
 >
 >