Our company has one, and it's a real lifesaver.  We mill lots of prototype
boards.  The machine is not cheap, I think ours cost between $5000 and
$10000, but we mill enough boards that it saves a lot of money and time.

It takes a while to mill a board, so you don't want to make production
quantities.  Around here, it's common to send out for etching if there are
10 to be made, but the 2- or 3-turns needed to get the design right are much
quicker with the milling machine.

You can mill boards from the same CAD files you will send to a board house,
but the milled boards still aren't EXACTLY like etched ones.  You still need
to test an etched one before you commit to volume production.  This is
especially true if you have RF stuff like we almost always do.

If you're a glutton for punishment, supposedly you can mill multilayer
boards by milling two or more boards and then gluing them together with
epoxy, but as a practical matter, they're limited to double-sided boards.

The milling machine is the greatest thing ever made for whipping up a
professional and finished-looking prototype to impress a potential big-$
customer.

It's fabulous for one-of-a-kind test fixtures.  Especially when you realize
6 months later that you need another one just like it (just hope you didn't
lose those old CAD files!)

> -----Original Message-----
> From: Jerry Merrill [mailto:jerrym@TECH-TOOLS.COM]
> Sent: Tuesday, March 28, 2000 1:46 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: [OT] PCB milling
>
>
> We are considering buying a table-top PCB prototype machine.
> These produce
> single and double sided boards by milling (rather than etching) away
> unwanted copper.
>
> Anybody wish to share their experiences with these devices?
> Costs, limitations, strengths?
>
>
> Jerry Merrill
>
> jerrym@tech-tools.com
> http://www.tech-tools.com
> FAX: (972) 494-5814
> VOICE:(972) 272-9392
> TechTools
> PO Box 462101
> Garland,  TX  75046-2101
>