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Subject: Re: [Homebrew_PCBs] Pick/Place (was:through hole P-n-P ?)

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-04-29

On Thu, 29 Apr 2004 09:09:05 -0000, ballendo <ballendo@...> wrote:

> Roy,
>
> I think it would be MUCH harder to make a homemade through hole pick
> and place! (To the degree that I won't even be trying...)
>
> Ballendo

I agree, I have no clue how the industrial machines manage to get the legs
in the holes.
I further see no reason why one should try such a thing.
If you can make a pick and place you can go smd and have the added benefit
of automatic soldering.
(yes i am aware this is possible too with throuhhole).

For i smd machine i would suggest using reeled parts, but maybe not really
using the reels.
just make an area at the side with little pegs holding the strips cut from
a reel, flat, straight.
then remove the plastic cover. the machine needs to know where to take the
part from and where to place
it. you only cut strips of the length you will need from your reels.

I think it would be much harder to make a sufficient number of "roll and
peel of the plastic cover"
pickup stations. I also think one can live without automatic placement of
the special parts
which you don't have on reels, maybe you could make a few "plase part
against that fixed edge by hand"
pickup stations.


It would be a help if the machine could precisely place all resistors and
capacitors, maybe diodes
and transistors too... because that is what you normally have in
machine-friendly reels.


I don't think the hardware would be that much of a problem, you need a
rotating vacuum holder of course.
(maybe one could replace the shaft of a stepper by a tube, or drill a hole
through it - this
way the work needed for this part would be minimal. a flexible hose to the
top with a "rotating" connector
and ready.

What i really wonder about is how it is possible to generate the needed
files.
I do not think this could be done automated from a layout file.
this is the reason why i most likely will never attempt such a machine.
It seems to make no sense for one-offs or only a few boards.

ST