Homebrew PCBs

----- Original Message ----- 
From: "Dave Mucha" <dave_mucha@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Wednesday, April 21, 2004 1:24 PM
Subject: [Homebrew_PCBs] Re: Pick and place rules for layout?


> --- In Homebrew_PCBs@yahoogroups.com, "mdgolfbum" <jim@j...> wrote:
> > Is there a website that describes rules for layout that will ensure 
> > adequate spacing for pick and place machines?
> > 
> > I'm doing a few by hand but if the project is successful I might 
> > have a shot a selling a thousand or so. Can't see myself sitting in 
> > the basement soldering finelines that long...
> > 
> > tnx
> > jtm
> 
> 
> I am in the same boat.
> 
> I have about 10 boards with smt parts that I would like to get done.  
> The next bunch will hopefully be 100 boards and then after that, 
> 1,000 boards.
> 
> I did a little checking and found one guy who will do boards for 
> something about 25 cents per SMT part and 75 cents per thru-hole 
> part.  yup, a resistor is a thru-hole and yes, I pay 2 cents for them 
> too.
> 
> 
> did more checking...
> 
> Outsource to China and the price structure changed to $200 set-up, 
> $250 engineering charge and two cents per part.  that is much better 
> for the 1,000 board project than the 10 board or 100 board ones.
> 
> I also just started looking into silkscreen or template for screening 
> on solder paste for toaster oven soldering.  That starts at about 
> $75.00 for a metal, laser cut stencil, or I can cut the solder pads 
> our of plastic with an exacto knife.  
> 
> Anyone know the thickness for solder paste ?
> 
> Alternately, a solder paste dispenser would be a great addition to 
> the shop.

This is a useful page:

http://www.pcbexpress.com/stencils/apply_solder_paste.php

The thickness is determined by the stencil thickness.

Leon