[Coco] Coco [OT] Circuit Prototyping

Gene Heskett gheskett at wdtv.com
Tue Jul 22 11:45:30 EDT 2014


On Tuesday 22 July 2014 09:18:07 Steve did opine
And Gene did reply:
> I agree that it's a bit pricy even for prototyping.
> 
> Like you, I'll use breadboards for early design and testing.  But even
> for my early prototypes, I still use PC boards.
> 
> Elecrow.com has 2 Layer 10 * 10 cm PC boards for $11.90.  That's not

Good site Steve, thanks for the link.

> just one board but five of them. Give them your Eagle CAM file and wait
> about two - three weeks for the low cost shipping ($4.77) option.  ($25
> in shipping, you will get it about a week.)  They are complete boards
> with solder mask, silk screen printing and holes drilled.
> 
> I've use them for for both prototypes and production runs and my last
> production of 50 units was only $1.10 per board.
> 
> Yes, KickStarted does have "neat" stuff from time to time.  But not all
> of it is practical.

I could be very tempted to add the led adjustment pots to my eagle files & 
have them make a few I could potentially sell, of the opto-interrupter 
board that encodes the spindle rotation on my lathe. So the software 
driving it, knows within 1.8 degrees of rotation where the spindle is at, 
even at (heaven forbid) 15,000 rpms. But the way I am geared, 1400 revs is 
about tapped out.  I have the software for the making of the slotted disk 
working well already, taking about 4 hours run-time as end mills that size 
are extremely fragile and 9-15$ a copy.

But making the board on my milling machine takes several hours, and does 
NOT have plated thru holes in spite of its being double sided. Out of all 
the converted 7x12 lathes out there, I may have the only one that can run 
BOTH the G76 canned single point threading cycle, and the G33.1 RIGID 
tapping cycle.

Now with ball screws on both axis's, it is still not a silk purse, but 
that sows ear is doing fairly well. ;-)
 
> On 7/22/2014 2:58 AM, S Klammer wrote:
> > Although this is likely to be of limited use, thought that some of
> > you may find it interesting.  A single sided circuit printer using a
> > conductive ink which also places SMD components using a conductive
> > glue.
> > 
> > I'd think that $200 of ink/glue is expensive for 50 boards, yet the
> > guick prototyping may be useful... but, you'd have to factor in the
> > sheet resistance of "87.5 mOhms / sq".
> > 
> > For the limited stuff I "play around with", I'll stick with
> > breadboarding.
> > 
> > https://www.kickstarter.com/projects/botfactory/squink-the-personal-e
> > lectronic-circuit-factory
> > 
> > Shain


Cheers, Gene Heskett
-- 
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Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS


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