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

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

> A good idea to use the less than full reels? Definitely. We are a
> hobby and small shop group, after all. But I'll use the machine to
> index even these short tapes, so the pickup point is the same for
> each part at a given "tape slot". Something perhaps non-obvious to a
> new cnc user is that the machine can do things in unusual ways. For
> instance, motion can be programmed to "press a button" before trying
> to pick up the part. The button can be ANYWHERE that ANY part of the
> machine can reach... So you might not "press it" with the z axis, but
> perhaps simply be moving the machine gantry to a certain place. This
> movement hits the switch to index the tape/reel. You could also use
> the needle of the vacuum pickup itself and an optical switch, firing
> a "one shot" in your macro... or in external hardware... Lotta ways
> to "skin this cat"...

"indexing" means you are going to move the strips, right?
I wonder how you plan to peel off the tape, i think it is definitely WAY
harder
to do this than fixed, "static" pickup bays.
I would simply peel the tape off the whole length.
Of course the file must look different, the part is on another position
each time.
But i do not think it is impossible, or any harder than moving the strips.
You can drill the holes for the "pegs" which hold the strips with the CNC,
thus make sure
everything is dead on spot and parallel.

ST