[TML] Molding Ships

[shadow at shadowgard.com]

On 1 Oct 2007 at 12:48, Bruce Johnson wrote:

> On Sep 29, 2007, at 6:13 PM, shadow at shadowgard.com wrote:
> 
> >
> > Actually, printed circuit boards could have been made well before
> > then. The modern "photo resist" tricks aren't necessary.
> >
> > I did my first board by using a brush to paint on the resist where I
> > wanted it. For mass production, a stencil and roller will work just
> > fine.
> 
> A printing press would work just fine. <http://www.handpress.org/>  
> see the platen jobber.
> 
> > I think the hardest part is getting the copper-clad board.
> >
> 
> Suitable materials were invented pretty early. I'd bet laquerware  
> would suffice, shellac mixed with wood flour was being used to mold  
> items as early as the 1850's. <http://www.bpf.co.uk/bpfindustry/ 
> History_of_Plastics.cfm>
> 
> Gluing the metal to the substrate is old tech.

The trick is finding something that won't react badly to the etching 
solution. And that won't come lose at a bad time.
 
> All said, making the things to solder ON to your 19th century  
> circuitboard would be rather lacking...:-) much simpler in those days  
> to use a breadboard anyway, since at best you're going to be using  
> discrete tubes and other components.

Printed circuits work just *fine* with tubes. But you want sockets 
for the tubes unless it's a "use once and toss" item like a proximity 
fuze.

Breadboarding is fine for initial layout and testing. But a cricuit 
board works better for production.

--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com